CMHC Canadian Wood Frame House Construction PDF
CMHC Canadian Wood Frame House Construction PDF
CMHC Canadian Wood Frame House Construction PDF
HOUSE CONSTRUCTION
CANADIAN WOOD-FRAME
HOUSE CONSTRUCTION
The information in this publication is based on the most current research results
available to CMHC and has been reviewed by housing industry experts. Readers are
advised to evaluate the information, materials and techniques carefully and to consult
appropriate professional resources to determine courses of action suitable for their
situations. The figures and text are intended as general practice guides only. Project and
site-specific factors of climate, cost, esthetics and so on must be taken into consideration.
Any photographs in this book are for illustration purposes only and may not necessarily
represent currently accepted standards.
Library and Archives Canada Cataloguing in Publication
Burrows, John, 1948Canadian Wood-Frame House ConstructionRev. ed.
Third Combined Imperial/Metric Edition T.p. verso
Updated to conform to the 2010 National Building Code of Canada and enhanced by
John Burrows, JF Burrows Consulting Inc., cf. Acknowledgements
Issued also in French under title: Construction de maison ossature de bois Canada.
Includes bibliographical references and index.
ISBN 0-660-19535-6
Cat. no.: NH17-3/2005
1. Wood-frame housesCanadaDesign and construction.
2. Wood-frame buildingsCanadaDesign and construction.
3. House constructionCanada. I. Canada Mortgage and Housing Corporation II. Title.
TH4818.W6B87 2005
694
C2005-980262-6
ACKNOWLEDGEMENTS
Richard Lind,
Everts Lind Enterprises, Lunenberg, N.S.
David Ricketts,
RDH Building Engineering Ltd.,
Vancouver, B.C.
Jasmine Wang,
Canadian Wood Council
Chris McLellan,
Natural Resources Canada
Barry Craig,
CMHC Policy and Research Division
TABLE OF CONTENTS
TABLE OF CONTENTS
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
xiii
How to Use This Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
New Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Choosing the Size and Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Metric and Imperial Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
11
Approvals, Permits and Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Planning and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Drawings, Financing and Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Site Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Protection and Care of Materials on the Building Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Excavation, Footings and Foundation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Floor Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Wall Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Roof Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
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Exterior Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Attics, Roof Spaces and Roofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windows, Doors and Skylights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windows and Skylights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Moisture, Air Leakage, Vapour Diffusion and Heat Transfer Control . . . . . . . . . . . . . . . . . . . . . .
Water Penetration Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Leakage Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vapour Diffusion Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heat Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plumbing, Electrical, Heating and Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heating and Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interior Wall and Ceiling Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Floor Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Decks, Porches and Balconies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Garages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
15
15
16
16
16
16
16
17
17
17
18
18
18
18
18
19
19
19
19
19
Stages of Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Building Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Excavation and Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Foundations, Drainage and Backfill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Doors and Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Plumbing, Heating, Electrical and Ventilation Rough-in . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Insulation, Air Barrier System and Vapour Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Exterior Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Interior Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Paint, Cabinets and Fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Landscaping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Chapter 3Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24
Ready-Mix Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
On-Site Mixing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Placing Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Curing Concrete . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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28
Grade Marks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Lumber Grades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Engineered Wood Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Sheet or Panel Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
33
Water Penetration Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Basement Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Walls Below Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Walls Above Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Air Leakage Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Air Barrier System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Location of the Air Barrier System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Air Barrier Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Basement Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Walls Below Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Walls Above Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Vapour Diffusion Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Vapour Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Location of the Vapour Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Basement Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Walls Below Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Walls Above Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Heat Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Types of Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Batt Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Loose-Fill Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Rigid Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Semi-rigid Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Foamed-in-place Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Amount of Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Basement Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Walls Below Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
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Exterior Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interior Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preserved Wood Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Insulating Concrete Form Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Walls Above Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Floors over Unconditioned Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Roofs and Ceilings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Truss or Rafter-Type Roof Ceilings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Joist-Type Roof Ceilings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
49
50
51
51
52
55
56
56
57
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
60
Marking the Excavation Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Excavation Size and Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Placement of the House . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
66
Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Wall Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Wood Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Column Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Stepped Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Formwork for Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Cast-in-place Foundation Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Floor-Wall Intersections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Control Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Insulating Concrete Form Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Concrete Block Foundation Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Slabs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Basement Floor Slabs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Slabs-on-ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Foundation Dampproofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Waterproofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Foundation Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Backfilling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Foundation Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
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89
Platform Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Balloon Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Advanced Framing Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Structural Strength . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Resistance to Lateral Loads Due to Wind and Earthquake . . . . . . . . . . . . . . . . . . . . . . . . 91
Low to Moderate Exposure Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
High Exposure Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Extreme Exposure Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
93
Sill Plates and Anchors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Columns and Beams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Beam and Joist Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Foundation Wall-Floor Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Sill-Plate Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Joist-Embedded Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Floor Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Floor Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Subfloor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Floor Framing at Projections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Choosing the Sizes of Built-Up Wood Beams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Choosing the Sizes and Spacing of Floor Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
108
Platform Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Braced Wall Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Balloon Framing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
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118
Pitched Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Prefabricated Roof Trusses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Site Assembly of Pitched Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Gable-End Framing and Projections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Low-Slope Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Roof Space Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Choosing the Size and Spacing of Ceiling Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Choosing the Size and Spacing of Roof Rafters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Choosing the Size and Spacing of Roof Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
136
Roof Sheathing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Installing Roof Sheathing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Roof Sheathing Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Eave Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Roof Coverings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Asphalt Shingles on Slopes 1:3 or Greater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Asphalt Shingles on Low Slopes of 1:6 to 1:3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Wood Shingles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Shakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Finish at Ridge and Hips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Built-up Roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Sheet Metal Roofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Concrete and Clay Tile Roofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
148
Types and Installation of Sheathing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Sheathing Membrane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Exterior Cladding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Metal and Vinyl Sidings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Horizontal Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Vertical Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
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Hardboard Siding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lumber Siding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Horizontal Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vertical Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plywood Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hardboard Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fibre Cement Board Siding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Corner Treatment for Siding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wood Shingles and Shakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stucco Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reinforcing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Masonry Veneer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exterior Insulation and Finish Systems (EIFS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
153
153
153
155
155
156
156
156
157
157
158
158
159
160
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Chapter 14Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
164
Designing for Factors that Influence Water Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Surface Tension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Capillary Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Kinetic Energy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Air Pressure and Pressure Differentials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Types of Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Base Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Counter Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Through-Wall Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Cap Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Dampproof Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Valley Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Stepped Flashing or Shingled, Stepped Base Flashing for Shingled Roofs . . . . . . . . . . . . . . . . . . 168
Drip Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Flashing Performance Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Water Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Movement Capability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Terminations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Durability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Buildability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
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173
Light, View and Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Airtightness, Water Resistance and Wind Load Resistance . . . . . . . . . . . . . . . . . . . . . . . 174
Energy Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Window Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Window Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Multiple Glass Layers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Low-Emissivity Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Gas Fills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Solar Heat Gain Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Edge Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Thermally-Efficient Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Window Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Window Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Exterior Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Resistance to Forced Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182
Skylights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
185
Eave Projection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Eave and Gable-End Intersections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Window and Door Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
Chapter 17Stairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
189
Stair Rise and Run . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Stairway Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Stringers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Basement Stairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Exterior Stairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Handrails and Guards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Ramps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
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TABLE OF CONTENTS
196
Chimneys and Flues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Masonry Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Factory-Built Flues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Masonry Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Factory Built Fireplace Inserts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Natural Gas Fireplaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
203
Cutting Framing Members . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Notching of Lumber Roof, Ceiling or Floor Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Drilled Holes in Joists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Notching and Drilling of Studs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Notching and Drilling of Top Plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Roof Trusses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Framing for Plumbing Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Framing Details for Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Location of Switches and Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212
Smoke Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
215
Space Heating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Forced Air Heating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Furnaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
Ductwork and Grilles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Electric Baseboard Heating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Hot Water Space Heating Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Space Heating System Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Air Conditioning Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Ventilation Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Natural Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Mechanical Ventilation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
System Design Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Heat and Energy Recovery Ventilators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223
Ventilation System Ductwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Operation and Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
TABLE OF CONTENTS
227
Gypsum Board Finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Nail Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Screw Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
Finishing Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Nail and Screw Popping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Wall Tile Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Other Finishes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
232
Sub-Floor and Underlay Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Wood Strip Flooring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Laminate and Engineered Flooring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Parquet Flooring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Resilient Flooring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Ceramic, Porcelain, Granite and Marble Tile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
238
Interior Doors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238
Door Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Hardware Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Trim and Mouldings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Millwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
Kitchen Cabinets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
Closets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
246
Composition of Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Types of Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Paint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Varnish and polyurethane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Stain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
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TABLE OF CONTENTS
Lacquer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Alkyd and Latex Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Comparison of Alkyd and Latex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Exterior Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Interior Coatings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
250
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
252
Loads and Sizing of Framing Members . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
256
Garages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
Carports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
259
Surface Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Driveways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Walkways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Chapter 29Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
261
Sustainable Housing Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Appendix ATables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
262
313
xii
PREFACE
xiii
PREFACE
NEW FEATURES
This edition of Canadian Wood-Frame House
Construction has been updated to reflect the
residential requirements of the 2010 edition of
the National Building Code of Canada (NBC),
including new energy efficiency requirements
in the 2012 Interim Changes to the 2010
NBC. Many other changes have been made
to bring the book in line with current building
science research, construction methods and
construction materials.
xiv
PREFACE
METRIC AND
IMPERIAL DIMENSIONS
Canadian Wood-Frame House Construction
provides both metric (SI) and imperial units.
The National Building Code of Canada
uses metric units and these govern whenever
strict interpretations of Code requirements
are required. Imperial units of measure
(feet and inches) are still commonly used
for wood-framing materials and house
construction technology.
Imperial sizes for lumber are nominal sizes
(the rough sawn sizes before planing and
dimensional changes resulting from drying).
For example, a wood member with a nominal
size of 2 4 in. has a finished size of about
112 312 in. The metric dimensions for lumber
are actual sizes (for example, 38 89 mm).
Every reasonable effort has been made to
provide accurate conversions of metric
dimensions to imperial equivalents; however,
it remains the responsibility of designers
and builders to comply with building code
requirements. Some conversion factors are
given in Table 1 (p. 263).
Consult the local building department to
determine the units measurement required
for house plans.
xv
CHAPTER 1
ADVANTAGES OF
WOOD-FRAME
CONSTRUCTION
Wood-frame construction can incorporate
dimension lumber, engineered wood products
and structural wood panel sheathing into
wall, floor and roof assemblies that are robust,
economical and fast to build. Current wood-frame
technology is the result of many years of
development and improvement and extensive
research by the National Research Council,
Canada Mortgage and Housing Corporation,
industry and others.
durable;
CHAPTER 1
Floor Framing
BUILDING DESIGN
Wood-frame housing may be built to
various designs and specifications. Whether
a standard design is used or a custom design
is created, building code provisions and good
design principles must be observed to provide
a durable house; to maximize occupant health,
comfort and safety; and to reduce a buildings
environmental footprint. Building design
should provide easy access for people of diverse
physical capabilities and adapt to occupants
changing needs. Obtain professional design
assistance for special requirements such as
barrier-free access for people with disabilities.
STRUCTURAL DESIGN
To agree with the National Building Code,
the metric spacing of wood framing members
is expressed as soft conversions from the actual
imperial dimensions. For example, spacing of
12, 16 and 24 inches on centre are converted
to 300, 400 and 600 mm on centre, respectively.
In order to suit the imperial sizes of common
1220 2440 mm (4 8 ft.) panel products, such
as gypsum board, OSB and plywood, the actual
spacing of framing members has been adjusted
to approximately 305, 406 and 610 mm on
centre, respectively.
The NBC contains provisions for bracing
to resist lateral loads from earthquakes and
high winds. The provisions are based on a
three-level risk-based approach developed
from environmental load data. There are no
special requirements for areas where the risk
is low to moderate. This means that normal
sheathing, cladding and finishes provide adequate
resistance. Most of the new requirements apply
to areas of high risk, mainly the coastal area of
British Columbia. For these areas, builders can
incorporate adequate lateral load resistance
without the need for further structural engineering
design. The measures include providing braced
wall panels in braced wall bands that are
FIRE SAFETY
The NBC does not explicitly require fire-rated
floor or wall assemblies in single-family houses.
Wood-frame construction is considered to
provide an acceptable level of fire safety,
dependent to a degree on gypsum board
finishes, which provide essential fire protection
of structural components for a certain period
of time. In addition, occupants are considered
to be familiar with hazards and safety features
of such buildings and to know how to safely
exit the house.
Wood-frame construction can satisfy the fire
safety provisions of the National Building Code.
Fire safety is a combination of many factors,
some of which can be minimized by building
requirements, and others that can only be
controlled by the occupants. Examples of
building code fire safety measures include:
CHAPTER 1
Floor Framing
SOUND CONTROL
Sound control between rooms of a house
is provided by means of the materials used
in the floor and wall assemblies and by
reducing flanking paths so that noise is not
transferred around assemblies. There are no
code requirements for additional sound control
measures in single-family houses because house
occupants can take measures to reduce noise.
When a higher level of sound privacy is needed,
acoustical insulation can be installed or other
measures taken with respect to floors and
partition walls.
Houses with a secondary suite are required to
have a higher level of sound privacy because
there could be two separate groups of occupants
in one house. Walls and floors between adjacent
dwellings must have sound-absorbing materials,
resilient channels on one side, and 12.7 mm
(12 in.) thick drywall on ceilings and both sides
of walls.
If a house is to be built in an area with a high
level of traffic or airport noise, an acoustic
engineer should be consulted to devise a means
to reduce external noise.
In multi-family buildings (such as semi-detached
or row houses or apartments), sound control
measures are required between all dwellings to
improve occupant comfort.
For more information, refer to the 2010 National
Building Code of Canada published by the
National Research Council of Canada.
Canada Mortgage and Housing Corporation
CHAPTER 1
Floor Framing
SECONDARY SUITES
A secondary suite is located in a house, townhouse
or semi-detached houses (two side-by-side
dwelling units) and used, for example, as a rental
unit or to accommodate family members in an
independent area of a house. A secondary suite,
which may also be referred to as an accessory
suite or secondary unit in some jurisdictions,
may occupy more than one storey or be on the
same level as or above/below the principal suite
in the house.
Some special building requirements apply to
secondary suites because the occupants activities
in one suite can affect the health and safety of
those in the adjoining suite. These requirements
are simpler and less costly than those pertaining
to apartment buildings, for example, and strike
a balance between practicality and cost, and the
health and safety of the occupants. Consultation
with local building officials is required before
a secondary suite is built. Some of the
considerations are as follows:
ROOM HEIGHT
Building codes establish minimum ceiling heights
for living area rooms. In general, the minimum
ceiling height is 2.1 m (6 ft. 11 in.). Unfinished
basement areas must have ceilings at least 2.0 m
(6 ft. 7 in.) high in any location that would be
used for passage.
RADON
Radon is a colourless, odourless, radioactive
gas that occurs naturally in the environment.
Outdoors, its concentration is negligible, but it
can accumulate in buildings to levels that pose
a health risk. Radon can seep from the ground
into buildings through cracks and unsealed
penetrations in the floor and walls abutting
the ground.
Although there are regions in Canada with
high radon levels, all new residential buildings
are now required to provide measures for radon
mitigation because (a) there are no reliable
maps showing where radon is present; (b) high
radon concentrations can be found in one
building and not in neighbouring buildings;
and (c) it is very difficult to detect problematic
CHAPTER 1
Floor Framing
ENERGY EFFICIENCY
IN HOUSING AND
SMALL BUILDINGS
Once adopted by the provinces and territories,
changes to NBC Part 9 will require that
building envelopes, heating, ventilating and
air conditioning systems and service-water
heating systems meet or exceed minimum
energy efficiency performance requirements.
Where adopted, the new provisions will have
an impact on the design and construction
of houses, so builders should stay alert for
building code amendments in their areas.
MATERIAL COMPATIBILITY
Many types of building materials are used in
a house. Experience has shown that materials
such as sealants and metals can adversely affect
an adjacent material at times, resulting in
premature degradation.
Many sealant products are suited to a wide range
of applications, and there is no simple and
universal product labelling system. Improper
selection can lead to problems such as paint
failure or damage to window frame finishes.
Connecting different metals can cause galvanic
corrosion, leading to premature failure.
Premature failure can also result from job
site-imposed conditions or deadlines. For example,
in the rush to apply paint in unheated conditions,
a painter might ignore the temperature range
recommended by the product manufacturer,
resulting in a costly recall.
CONSTRUCTION SAFETY
Care should be taken during construction to
avoid injuries, and the following require attention:
CHAPTER 1
Floor Framing
PROTECTION AGAINST
MOISTURE AND TERMITES
Wood-frame construction has a record of
long-lasting performance. Like all materials,
wood has advantages and disadvantages, and
some precautions are needed to ensure long
service life.
CHAPTER 1
Floor Framing
Preservative Treatment
In applications where wood cannot be kept
dry, other measures such as the use of
preservative-treated wood must be taken
to provide reasonable service life.
Alkaline copper quaternary (ACQ) and copper
azole (CA) are the most common preservatives
used for residential wood products and are
distinguished by the green colour of the
finished product.
Borate, another chemical used to treat wood
against termites and decay, is usually colourless
and results in a much deeper penetration of the
chemical into the wood than other methods.
However, borate tends to leach out of wood
that is exposed to rain, so it is approved only
for uses where the wood is protected from
direct exposure to moisture.
Corrosion-resistant fasteners such as those
that are hot-dip galvanized or made of
stainless steel should be used with treated
CHAPTER 1
Floor Framing
Resource
Efficiency
Environmental
Responsibility
Energy
Efficiency
Sustainable
Housing
Affordability
CHAPTER 1
Floor Framing
Continued
Energy Efficiency
Resource Efficiency
Environmental Responsibility
CHAPTER 1
Floor Framing
Continued
Affordability
RELATED PUBLICATIONS
2010 National Building Code of Canada,
National Research Council of Canada
Collecting and Using Rainwater at Home: A Guide for Homeowners,
Canada Mortgage and Housing Corporation (product no. 67925)
Engineering Guide for Wood Frame Construction 2009,
Canadian Wood Council (reference no. EGWF-09-E)
Guide for Radon Measurements in Residential Dwellings (Homes),
Health Canada (catalogue no. H128-1/08-543E)
Household Guide to Water Efficiency,
Canada Mortgage and Housing Corporation (product no. 61924)
Reducing Radon Levels in Existing Homes: A Canadian Guide for Professional Contractors,
Health Canada (catalogue no. H128-1/11-653-1E)
10
CHAPTER 2
APPROVALS, PERMITS
AND INSPECTIONS
The system of approvals, permits and inspections
for house construction can be quite complex.
It is important to ensure that the property is
zoned for the intended use before proceeding
with house planning. Some properties may have
development regulations, covenants or restrictions
governing the size, location and exterior finishes
of the house.
Requirements for drawings, permits and
inspections vary across Canada, and special
provisions may apply to suit local climatic and
geological conditions. For example, the wet
climates of both the east and west coasts require
a drainage cavity in walls to resist rain penetration;
varying snow loads across Canada result in the
different structural capacities for roof members;
Canada Mortgage and Housing Corporation
11
CHAPTER 2
Planning, Design and Construction
Zoning and
Environmental Approvals
Site Plan, Working Drawings
and Specifications
Building Permit
Plumbing Permit
Heating Permit
Electrical Permit
Utility Permit (Gas/Propane)
Health Unit Permit
(Wells/Septic Systems)
Excavation and
Footings Inspection
Pre-Backfill Inspection
POSTCONSTRUCTION
STAGE
CONSTRUCTION
STAGE
Framing Inspection
Completion Inspection
(Interior and Exterior)
Certificate of Occupancy
12
CHAPTER 2
Planning, Design and Construction
Site Planning
Site drainage
catch basin
13
CHAPTER 2
Planning, Design and Construction
14
CHAPTER 2
Planning, Design and Construction
Roof Framing
Framing
Wood-frame construction is comprised of
main structural members (the framing) and
sheathing (oriented strand board or plywood
that provides stiffness). The combination of
framing members and sheathing provides
rigidity, space for insulation and a framework
for supporting interior finishes and exterior
components. See Chapters 8 to 11 for
more information.
Floor Framing
Wall Framing
Exterior Finishes
In addition to enhancing appearance, exterior
finishes serve as a barrier to the elements.
The cladding is the first plane of protection
for water penetration control. Exterior finishes
include a wide variety of cladding materials
(wood siding, brick veneer, vinyl siding,
cementitious siding) as well as flashing, trim
boards and sealant. Windows and doors and
the roof covering are also part of the exterior
finishes. See Chapters 5, 12 and 13 for more
information on exterior finishes.
Flashing
The purpose of flashing is to prevent water from
entering the building envelope and to intercept
any that passes the first plane of protection and
direct it to the exterior. Flashing is usually
required wherever there is a discontinuity on
exterior surfaces (for example, above windows),
where there is a change in cladding materials
(for example, vinyl siding above brick cladding),
and at roof valleys. Carefully plan the location of
flashing to fit with roofing materials, brick joints,
sheathing membranes, windows, skylights and
doors. See Chapter 14 for more information.
Canada Mortgage and Housing Corporation
15
CHAPTER 2
Planning, Design and Construction
Doors
Stairs
Stairs provide access for people, furniture and
appliances; and must be wide enough and
have sufficient headroom to provide safe passage.
Falls on stairs are a major source of accidents,
and risk is reduced by strict adherence to code
requirements for the width, rise and run of stairs.
See Chapter 17 for more information.
16
CHAPTER 2
Planning, Design and Construction
17
CHAPTER 2
Planning, Design and Construction
Plumbing
Electrical
18
CHAPTER 2
Planning, Design and Construction
Floor Coverings
Floors are subject to wear and tear. Higher-quality
finish flooring can often be cost effective because
it will likely last longer than less expensive
flooring. The sub-flooring must be adequate
to support the finished flooring, especially
ceramic tile. Planning the type of finished
flooring to be used can minimize elevation
differences (tripping hazards) between different
flooring materials. See Chapter 22 for more
information. Consider polished concrete as a
finished floor, especially in areas where concrete
can capture and radiate solar heat.
Garages
Attached garages are popular and common in
Canadian houses. Because of the risk of carbon
monoxide getting into the house and the likely
storage of paints, gasoline and other chemicals
in the garage, it must be separated from the
house by an effective air barrier system. If there
is a connecting door, it must be tightly fitted
Canada Mortgage and Housing Corporation
19
CHAPTER 2
Planning, Design and Construction
STAGES OF CONSTRUCTION
20
CHAPTER 2
Planning, Design and Construction
Building Layout
Framing
Foundations, Drainage
and Backfill
Foundations can be placed in one day by a
skilled contractor and require at least one week
for concrete to cure before formwork can be
removed. Dampproofing, foundation drainage
systems and backfill requires another day or two.
Additional measures for foundation drainage
such as waterproofing, sump pumps, ditching or
dry wells may be required. Backfilling should
not begin before the first floor framing has
been anchored to the foundation and the first
floor sub-floor has been installed because the
floor framing helps to resist the soil pressure.
Contact your building official to inspect the
footings and foundation and municipal
service connections.
21
CHAPTER 2
Planning, Design and Construction
Exterior Finishes
Landscaping
Interior Finishes
This stage includes the installation of ceiling,
wall and floor finishes, shelving and cabinets.
Finishing carpentry for interior doors, frames
and trim along with stair balusters and handrails
is usually done immediately after the floor,
wall and ceiling finishes have been prepared
for painting and varnishing. The interior
finishing stage normally requires about two
weeks to complete.
22
CHAPTER 2
Planning, Design and Construction
RELATED PUBLICATIONS
About Your House: Canadas Housing Construction System,
Canada Mortgage and Housing Corporation (product no. 62966)
About Your House: Photovoltaics (PV) Systems,
Canada Mortgage and Housing Corporation (product no. 63890)
23
CHAPTER 3
Concrete
24
CHAPTER 3
Concrete
READY-MIX CONCRETE
Ready-mix concrete is available in most
urban areas. Manufactured in plants to
established mix designs, the quality of
ready-mix concrete can be tailored to
meet strength, durability, and workability
requirements of a particular application.
Workability is attained by the ready-mix
provider meeting the water-cement ratios
set out in CSA Standard A23.1-09: Concrete
materials and methods of concrete construction.
ON-SITE MIXING
When mixing must be done on site, the water
and aggregate should be clean and free of
organic material or other substances that might
damage the concrete. The aggregates should
also be well-graded, in other words, with the
correct proportion and size of fine and
course aggregates.
The air-entraining admixtures must be added
according to manufacturers recommendations
adding too much will decrease concrete strength.
Air-entraining admixtures should be used only
in concrete mixed in a motorized mixer.
On-site mixing can use premixed bags of
cement and aggregate. In such cases, follow the
manufacturers instructions to obtain the desired
strength and durability. If site-mixed concrete is
to be proportioned on site, determine the correct
ratios of fine and coarse aggregates, cement and
PLACING CONCRETE
Place concrete into forms continuously in
horizontal lifts not exceeding 1.2 m (4 ft.) in
depth. Do not allow concrete to fall into the
forms from a height of more than 2.4 m (8 ft.)
as this causes the concrete to segregate. For higher
drops, use a pipe to deposit the concrete. Buggies,
wheelbarrows, chutes or pumping can be used
to move the concrete to locations not accessible
to ready-mix trucks. The chutes should be
metal or metal-lined with round bottoms
and sloped with a rise-to-run inclination
between 1:2 and 1:3.
Do not deposit the concrete in a pile. Spread
and level it by raking or shovelling. Use vibrators
to consolidate the concrete but not to move it
horizontally. Compact the concrete uniformly by
means of tamping hand tools (puddling sticks)
or, preferably, by a vibrator.
If it is necessary to interrupt concrete placement,
the surface of the concrete placed in the forms
should be levelled. If partial setting has started
by the time concrete placement is ready to
resume, roughen and dampen the surface to
25
CHAPTER 3
Concrete
CURING CONCRETE
Newly placed concrete must be cured for a
set period of time to allow the concrete to
achieve its potential strength, water tightness
and durability, and to minimize cracking.
To cure, concrete must be kept damp and
within a limited temperature range. Wall forms
should be left in place for at least three days
to retain moisture for proper curing, and longer
if possible. After the forms have been removed,
the curing should continue at least another
day if the concrete temperature is kept above
21C (70F), and for another three days if
the concrete temperature is kept between
10C (50F) and 21C (70F).
26
CHAPTER 3
Concrete
RELATED PUBLICATIONS
CSA Standard A23.1-09/A23.2-09: Concrete materials and methods of concrete
construction/Test methods and standard practices for concrete,
Canadian Standards Association
27
CHAPTER 4
GRADE MARKS
Lumber used for construction in Canada is
grade-stamped to show that it conforms to the
National Lumber Grades Authority (NLGA)
grading rules for Canadian lumber. The grading
and grade marking of lumber must also conform
to CSA Standard O141-05 (R2009): Softwood
Lumber. A grade stamp indicates the grading
agency, the species or species combination
designation, the grade, the moisture content
at the time of manufacture and the mill number.
Facsimiles of Canadian grade marks are shown
in Table 9 (p. 269).
S-GRN in the grade mark signifies that the
lumber was surfaced at a moisture content
higher than 19 per cent to a size that would
allow for natural shrinkage during seasoning.
S-DRY in the mark indicates the lumber was
surfaced at a moisture content not exceeding
19 per cent. KD (kiln-dried) indicates that
lumber has been dried in a kiln to a moisture
content of 19 per cent or less. The moisture
28
LUMBER GRADES
Each piece of construction lumber is examined
and assigned a grade depending on its physical
characteristics such as the size and location of
knots and the slope of the grain. The assigned
grade is an estimate of its strength.
Softwood lumber species having similar
strength properties may be combined into
a single-species combination and marketed
under a group designation. The most common
group is spruce-pine-fir (SPF). The Canadian
commercial species combinations and their
characteristics are shown in Table 10 (p. 271).
Select Structural grade is used where
high-strength, stiffness and good appearance
are required. No. 1 grade may contain some
percentage of Select Structural material, but
permitted knots are slightly larger. Tests have
shown that No. 1 and No. 2 grades of lumber
have the same strength and therefore, No. 2
and better is a typical grade category for most
general construction uses.
There are two types of machine-graded lumber:
machine-stress-rated (MSR) lumber; and
machine-evaluated lumber (MEL). Both MSR
and MEL are produced using non-destructive
stiffness measuring machines.
The grade stamp on MSR and MEL
indicates strength properties. MSR and MEL
are most often used in applications where
strength is crucial, such as for manufacturing
wood trusses.
ENGINEERED WOOD
PRODUCTS
Several types of engineered wood products
(EWPs) are routinely used in wood-frame
house construction. These products can provide
equivalent or superior strength compared with
dimension lumber and are typically manufactured
using less wood fibre and available in long
lengths. They include: wood I-joists, glulam,
plywood, oriented strand board (OSB),
laminated veneer lumber (LVL) and others.
Dimension lumber and other wood products
are often combined in the manufacture of EWPs
29
Examples of engineered
wood products
wood web
wood I-joist
30
Resource Efficiency
Energy Efficiency
31
Continued
Environmental Responsibility
Affordability
RELATED PUBLICATIONS
Wood Products,
Canadian Wood Council (web content available at www.cwc.ca)
CSA Standard O141-05 (R2009): Softwood Lumber,
Canadian Standards Association
32
CHAPTER 5
33
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
WATER PENETRATION
CONTROL
The building envelope for a wood-frame house
controls exterior precipitation (usually water
from rain, snow and ice melt) by deflecting
moisture away from a wall, draining any moisture
that penetrates into the building envelope back
to the exterior, and allowing any accumulated
moisture to dry over time. See Chapters 12 to 15
for specific construction details.
All walls are required to have a primary and a
secondary line of defence against rain penetration.
The first plane of protection is typically the
cladding (for example, siding, masonry or
stucco). It includes accessories such as trim
or caps that are part of the cladding system.
The second plane of protection ordinarily
consists of a sheathing membrane or insulating
sheathing, flashing, sealants and other materials,
and is intended to:
34
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Basement Floors
Basement floors are usually constructed on dry
sites or have sufficient drainage such that water
penetration control is not a primary concern.
Polyethylene sheet dampproofing is normally
placed over granular material before the concrete
slab is poured to reduce the amount of moisture
entering the basement from below the slab.
When bulk water penetration is a concern,
a waterproof membrane is applied over a slab
at least 75 m
m (3 in.) thick, and a second slab
at least 75 mm (3 in.) thick is poured over the
membrane. The waterproof membrane must
be connected to the wall membrane to form a
complete seal.
35
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Roofs
On pitched roofs with slopes where the rise
and run are equal to or greater than 1:6,
asphalt-saturated sheathing paper is applied
over the roof sheathing to provide a secondary
plane of protection to water that may penetrate
beyond the primary plane of protectionthe
shingles, tiles or metal roofing.
Canada Mortgage and Housing Corporation
36
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
37
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
38
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Basement Floors
A concrete floor or polyethylene sheet can
serve an air barrier. The floor air barrier must
be sealed to the air barrier in the below-grade
walls. This can be done by caulking the joint
between the floor and basement walls.
sealant
39
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
wall studs
bottom wall plate
(second floor)
floor joist
vapour barrier and batt
or spray foam insulation
40
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
drainage space
wood siding
weather resistive barrier (WRB)
over flashing
head flashing extends min. 100 mm
(4 in.) window beyond both sides
WRB over top of window frame
window frame
double glazing
trim around window
foam insulation
backer rod and interior sealant
41
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
drainage space
wood furring
trim
backer rod and sealant
(or spray foam) to connect the
wall air barrier to the window
window shims
foil-faced, self-adhered membrane
sill flashing complete with end-dams
exterior trim
sheathing membrane (air and water barrier)
sheathing
cavity insulation
cladding (any type)
exterior insulation
drainage space
42
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Roofs
It is common to install the ceiling air barrier
before the interior partitions are built, because it
is easier to make an airtight connection between
the wall top plates and unconditioned spaces
(such as attics). Alternatively, when the interior
12 Polyethylene strips at end of partition and over wall top plates to provide
continuity of the air barrier
house-wrap AB tab
over top plates of
interior and exterior
stud walls below roof
polyethylene VB tab
between interior and
exterior stud walls
43
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
VAPOUR DIFFUSION
CONTROL
Water vapour can migrate through building
envelope assemblies by penetrating through
materials by diffusion. Many activities such
as cooking, dishwashing, laundering and
bathing release considerable amounts of
water vapour into the air and increase its
humidity. As water vapour diffuses through
assemblies, it can condense on cold surfaces
such as the inside face of the exterior sheathing
and cause deterioration.
Vapour Barrier
In the winter, the air inside the house may
contain more water vapour than the outside air.
This causes a difference in vapour pressure and
creates a driving force that can lead to water
vapour diffusing through materials into the
building envelope. Many building materials
are permeable to the passage of water vapour,
but those classified as vapour barriers, such as
polyethylene sheet, have very low permeability
and are very resistant to diffusion.
44
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Basement Floors
Dampproofing and air barrier protection against
radon leakage into conditioned spaces is usually
provided by a sealed polyethylene barrier under
the basement slab. This arrangement also
constitutes a vapour barrier.
45
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Roofs
Sheet polyethylene is usually used as a vapour
barrier in ceilings separating conditioned space
from attic space.
Insulation
The effectiveness of a building assembly such as
a wall or ceiling in resisting the flow of heat is
measured as its thermal resistance or RSI-value
in metric units (R-value in imperial units).
Although materials used for structure, cladding
Types of Insulation
Insulation is manufactured from a variety
of materials and in various forms. The most
common types of insulation used in wood-frame
housing are described below.
Batt Insulation
Batt insulation is made from fibres of glass,
mineral or steel-mill slag spun together with
a binding agent. The product comes in lengths
and widths to fit standard framing spaces and
in a range of thicknesses that provide different
RSI-values (R-values). Most batt insulation is
called friction fit because it is made slightly
wider than the standard framing space and
held in place by friction. Batts should not be
compressed to fit a smaller space because this
reduces the insulation value.
46
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Loose-Fill Insulation
Amount of Insulation
Rigid Insulation
Rigid insulation is manufactured in sheets or
boards using materials such as polyisocyanurate
and expanded or extruded foamed plastic
and is usually applied to flat surfaces such as
walls. Extruded polystyrene has low moisture
permeability and can be used in damp conditions
such as on below-grade walls.
Semi-rigid Insulation
Semi-rigid insulation boards are made of glass or
mineral fibres and usually applied to flat surfaces
such as walls. They are more flexible than rigid
insulation products and not as easily damaged by
impact or bending. Some semi-rigid insulation
has good drainage properties and can be used on
below-grade walls.
Foamed-in-place Insulation
Specially formulated polyurethane and
isocyanurate insulations can be installed
by spraying or injecting under pressure.
The liquid sets into a rigid mass within minutes
of installation. Some products develop heat or
expand during the curing process. Ensure that the
products being installed are approved for use in
houses, and have a qualified contractor perform
the installation under well-ventilated conditions.
47
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Basement Floors
Insulation is generally not required under
basement floors that do not contain heating
elements. RSI-2.32 (R 13) insulation must
be placed under heated floor slabs in climate
zones up to 4999 HDD, and RSI-2.85 (R 17)
is required in colder climates. Extruded
polystyrene is commonly used under basement
floors because it is resistant to damage from
water and is strong enough to support most
floor loads.
48
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
base flashing
batt insulation
vapour barrier tightly fitted to framing
sill plate barrier
12 mm (12 in.) cement parging on
wire lath nailed to sill plate
and concrete
type 4 extruded polystyrene,
or type 2 expanded polystyrene,
or rigid glass fibre insulation
bonded to concrete
granular backfill around insulation
to protect against damage due to
frost heave
concrete wall
49
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Interior Insulation
Foundation walls may be insulated on their
interior surfaces. Framing materials should be
separated from a concrete wall by dampproofing
materials. Polyethylene should not be used for
this purpose with new concrete walls because it
does not allow the drying of moisture escaping
from the concrete. Building paper protects the
framing and insulation from moisture damage
by conducting the moisture to the bottom of
the wall. Alternatively, expanded or extruded
polystyrene insulation may be installed against
the concrete foundation wall prior to the framing,
caulking
concrete wall
50
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
51
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
52
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
sheathing
membrane
air/vapour barrier
between joists
siding
loose-fill insulation
sheathing
53
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
21 Brick veneer cladding with insulation in the framing space and outboard
12.7 mm (12 in.) gypsum board
polyethylene sheet
batt insulation
38 x 140 mm (2 x 6 in.) framing
rigid insulation sheathing
sheathing membrane (air barrier)
100 mm (4 in.) clay brick
25 mm (1 in.) air space
54
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
finish flooring
polyethylene
vapour barrier
friction fit or
loose fill insulation
wood floor joists
vapour-permeable
air barrier material
wire lath (or other
suitable material)
55
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
56
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
57
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Energy Efficiency
Resource Efficiency
58
CHAPTER 5
Functions of the Building Envelope: Water, Air, Vapour and Heat Control
Continued
Affordability
RELATED PUBLICATIONS
2010 National Building Code of Canada (Part 9.36 and Appendix C),
National Research Council of Canada
2011 National Energy Code for Buildings,
National Research Council of Canada
Building Enclosure Design Guide, Homeowners Protection Office (HPO),
British Columbia
Building Envelope Guide for Houses, Homeowners Protection Office (HPO),
British Columbia
Canadian Home Builders Association Builders Manual,
Canadian Home Builders Association
59
CHAPTER 6
MARKING THE
EXCAVATION AREA
Check with the municipality or township for
minimum setback and side yard requirements
before deciding the exact location of the house
on the site. The proximity of the house to a
property line can also affect such things as the
size of window openings, soffits and exterior
cladding so that the house does not pose a fire
risk to a neighbouring house.
Always check with local utility companies prior
to digging to ensure that the excavation will not
interfere with buried services. Inadvertently
cutting telephone, gas or power lines can prove
costly and result in injury. After the site is
cleared, mark the perimeter of the house using
the exact location of the corners of the lot as a
reference. The latter are usually determined by
a certified surveyor, marked by small wooden
stakes accurately located at each corner, with
nails driven into their tops indicating the outside
line of the foundation walls.
60
CHAPTER 6
Location and Excavation
batter board
taut line
plumb bob
nail
1.2 m (4 ft.) minimum
outside line of
foundation wall
4m
t.)
2f
(1
3m
(9
ft.)
5 m (15 ft.)
EXCAVATION SIZE
AND DEPTH
Before excavating begins, topsoil should be
stripped and stored for reuse. Some excavated
material suitable for backfill may be stored on
site and surplus material removed from the site.
The depth of the excavation is established during
the planning stage, depending on the access to
the street, sewer and water services, the profile
of the lot, the level of finished grade around
the perimeter of the house and the elevation
of adjoining properties.
61
CHAPTER 6
Location and Excavation
62
CHAPTER 6
Location and Excavation
batter board
dryline
plumb line which
represents the
foundation wall
corner line
back slope
workspace for
tradespeople
wall-footing junction
footing on
undisturbed soil
using formboards
subsoil
63
CHAPTER 6
Location and Excavation
Environmental Responsibility
Energy Efficiency
Resource Efficiency
Affordability
64
CHAPTER 6
Location and Excavation
RELATED PUBLICATIONS
2010 National Building Code of Canada,
National Research Council of Canada
About Your House: Photovoltaic (PV) Systems,
Canada Mortgage and Housing Corporation (product no. 63890)
Glossary of Housing Terms,
Canada Mortgage and Housing Corporation (product no. 60939)
Landscape Guide for Canadian Homes,
Canada Mortgage and Housing Corporation (product no. 63523)
Collecting and Using Rainwater at Home: A Guide for Homeowners,
Canada Mortgage and Housing Corporation (product no. 67925)
65
CHAPTER 7
FOOTINGS
Footings receive house loads through foundation
walls or columns and transmit these loads to
the soil. The type and size of footings must
be suitable for soil conditions and be located
below the frost level. Alternatively, they must
be placed on material that is not susceptible to
frost action or otherwise protected by exterior
insulation. Insulation may be used to protect
shallow foundations from frost, but this requires
a professional design. Because water must be
present for frost to occur, frost action can be
further minimized by providing good drainage
around the foundation to direct water away
from the building.
Footings should rest on undisturbed soil, rock
or compacted granular material. The latter must
not contain pyritic shale, a material found in the
St. Lawrence lowlands and prone to swelling.
Wall Footings
The size of wall footings should comply with
building code requirements. Table 4 (p. 265)
shows minimum concrete sizes for average,
stable soil and the number of stories supported.
If the distance to the water table from the bearing
surface is less than the width of the footings,
the footing sizes in Table 4 must be doubled.
Footings should project beyond each side of
the wall by at least 100 mm (4 in.), and the
thickness of unreinforced footings should be
no less than their projection beyond the wall.
Footings must never be less than 100 mm
66
CHAPTER 7
Footings, Foundations and Slabs
Wood Footings
Continuous preserved wood footings are often
used instead of concrete footings for preserved
wood foundations. Wood footings and the
required granular drainage layer act together to
distribute loads from the structure to undisturbed
soil. The sizes of interior and exterior footings
are provided in the Canadian Wood Council
publication entitled Permanent Wood Foundations.
31 Size of footings
wall thickness
projection
key
polyethylene
capillary break
67
CHAPTER 7
Footings, Foundations and Slabs
Column Footings
Locate footings for posts or columns (Figures 32
and 33) so that the members they will support
are centred. Footings vary in size depending on
the allowable soil pressure and the load they
support. On average stable soil, common sizes
are 0.4 m2 (4.3 sq. ft.)about 640 640 mm
(25 25 in.)for one-storey houses and 0.75 m2
(8 sq. ft.)870 870 mm (34 34 in.)for
two-storey houses. The thickness of column
footings without reinforcement must be at
dampproofing
granular fill
steel bearing plate
grout to level bearing plate
thickness
projection
concrete footing
68
CHAPTER 7
Footings, Foundations and Slabs
Stepped Footings
Stepped footings may be required on sloping
sites or where there is an unstable soil pocket
under a footing. They may also be required
35 Stepped footings
grade entrance
finished grade
600 mm (24 in.)
minimum step length
footing on undisturbed soil
69
CHAPTER 7
Footings, Foundations and Slabs
FOUNDATIONS
A foundation wall transfers the floor, wall,
roof and other building loads (including
snow and occupant loads) down to the footings.
The four most common types of foundations
are cast-in-place concrete, concrete blocks,
insulating concrete forms (ICF) and preserved
wood. Precast concrete may also be used.
minimum thickness
required in Table 1A
minimum thickness required to
accommodate insulation and
support brick veneer above
70
CHAPTER 7
Footings, Foundations and Slabs
wall thickness
break point
reusable forms
plywood or other facing
waler
horizontal bracing
diagonal brace
if required
form tie
stake
block
anchor bolt
cast-in-place concrete wall
strip footing
71
CHAPTER 7
Footings, Foundations and Slabs
sill plate
opening for window installation
caulking
preservative-treated
wood blocking
slope to exterior
90 mm (312 in.)
minimum bearing
steel bearing plate
separate wood beams installed less than 150 mm (6 in.)
above grade from concrete with dampproofing material,
such as 0.15 mm (6 mil) polyethylene.
72
CHAPTER 7
Footings, Foundations and Slabs
40 Method of anchoring floor system to concrete walls, showing anchor bolt for
wood sill
rim joist
foundation
joist
38 mm (112 in.) minimum
joist bearing
anchor bolt, nut and washer
sill plate
mortar bed or foam gasket
73
CHAPTER 7
Footings, Foundations and Slabs
Floor-Wall Intersections
Control Joints
12 mm
(12 in.)
control crack
19 mm (34 in.)
19 mm (34 in.)
bevelled 19 mm (34 in.) strip
nailed to inside and outside form
face to make grooves
Note: The combined thickness of inner and outer strips should equal approximately one-fifth of the wall
thickness. This example is for an 200 mm (8 in.) thick foundation wall.
74
CHAPTER 7
Footings, Foundations and Slabs
Insulating Concrete
Form Foundations
Insulating concrete form (ICF) foundations
are made up of two polystyrene faces held
apart by permanent plastic or metal spacers
and are being used increasingly in Canada.
exterior finish
subfloor
floor joist
vapour-permeable
air-barrier material
rim joist
sill plate
rigid insulation
flashing
form tie
parging finish
above grade
gypsum board
75
CHAPTER 7
Footings, Foundations and Slabs
190 mm (8 in.)
190 mm
390 mm
190 mm
Corner
Stretcher
190 mm
190 mm
390 mm
Beam or lintel
190 mm (8 in.)
100 mm
100 mm (4 in.)
Sash
50 mm (2 in.)
190 mm
390 mm
Solid top
190 mm
190 mm
190 mm
Beam or lintel
76
CHAPTER 7
Footings, Foundations and Slabs
solid cap
pilaster for support
of beams
sill
concrete block
blocking for
window frame
parging
dampproofing
footing
cove
77
CHAPTER 7
Footings, Foundations and Slabs
Company Name
and Logo
PWF - FBT
78
CHAPTER 7
Footings, Foundations and Slabs
finished grade
(minimum slope of 1 in 12)
free-draining backfill
treated exterior plywood
polyethylene
(stops at grade)
gravel bed 125 mm (5 in.) minimum
framing strap
treated wall stud
treated plywood cover
38 x 89 mm (2 in. x 4 in.)
treated blocking between
studs (backing at panel joint)
treated wall plate
treated footing plate
treated screed board
concrete slab
polyethylene
treated subfloor
treated floor joist
polyethylene
treated wood sleeper
polyethylene and
exterior sheathing
Note: Shaded areas indicate those members that are preservative treated.
79
CHAPTER 7
Footings, Foundations and Slabs
SLABS
Concrete slabs are used for basement floors
and for houses or portions of houses constructed
at grade. In small buildings, they are generally
supported by the ground below and not by
perimeter foundations.
80
CHAPTER 7
Footings, Foundations and Slabs
1.
2.
3.
4.
5.
6.
1
2
3
4
5
5
Note: The diamond-shaped joints (6) may be omitted if column footings are below floor level and the
column is wrapped with two layers of sheathing membrane or joint filler to break the bond.
81
CHAPTER 7
Footings, Foundations and Slabs
Slabs-on-ground
Because slabs-on-ground have requirements
similar to those pertaining to basement floor
slabs, the steps and precautions described for
the latter apply here as well. An important
difference is the need to establish the finish
floor level at a sufficient height above the natural
grade so that the finished grade will provide
good drainage away from the house (Figure 49).
The top of the slab must be at least 150 mm
(6 in.) above finished grade.
Remove all debris, stumps and organic matter
from the area below the slab and fill voids with
compacted granular material to provide a smooth
surface free of soft pockets.
stud
air/vapour barrier
insulation
drywall
finish flooring
concrete slab reinforced
82
CHAPTER 7
Footings, Foundations and Slabs
FOUNDATION
DAMPPROOFING
Dampproofing is necessary for all
foundations that contain habitable space to
restrict the movement of soil moisture into
the wall. Dampproofing materials include
bitumen, polyethylene or other sheet material.
In poorly-drained soils or soils with a high water
table, waterproofing will be required.
Dampproof concrete and unit masonry walls
below grade with a heavy coat of bituminous
material applied on the exterior surface from the
footings to the finished grade line. Such a coating
is usually sufficient to make the wall resistant
to surface water moving down to the footing
drainage system. Mineral fibre insulation or
drainage layers are recommended to drain water
away from the foundation walls.
WATERPROOFING
Waterproofing is needed where there is a
likelihood of hydrostatic water pressure and
requires the services of a qualified professional
to identify which measures are to be taken to
deal with the water and the forces imposed on
the foundation. Waterproofed foundations need
not be dampproofed. For walls, waterproofing
consists of an impermeable membrane, such as
two layers of bitumen-saturated felt. The layers
of felt are attached to the wall and each other
and covered with liquid bitumen. Waterproofing
materials for ICF foundations must be compatible
with the foam formwork/insulation.
Floor slabs must also be waterproofed
where hydrostatic pressure could be an issue.
The waterproofing materials must consist of a
membrane sandwiched between two layers of
concrete, each layer not less than 75 mm
(3 in.) thick. The floor membrane must be
sealed to the wall membrane. In many cases,
83
CHAPTER 7
Footings, Foundations and Slabs
FOUNDATION DRAINAGE
damp-proofing
84
CHAPTER 7
Footings, Foundations and Slabs
85
CHAPTER 7
Footings, Foundations and Slabs
BACKFILLING
Place backfill after the first floor joists and
subfloor are in place because they provide lateral
support for the foundation walls. This applies
to concrete, ICF, masonry and preserved wood
foundation walls. Table 5 (p. 265) shows the
maximum height from basement floor to finished
grade for both laterally supported and laterally
unsupported foundation walls.
Backfill material within 600 mm (24 in.) of the
foundation should be free-draining granular
material (not subject to ice lensing). It should
be free of large rocks, clay clumps, construction
waste and pyritic shales. These materials can
cause pressure points on the foundation wall,
damage dampproofing or waterproofing
membranes, and impair proper drainage
around the foundation.
Unequal backfill loading against foundation walls
can cause movement or cracking. Therefore,
deposit backfill material uniformly around
the perimeter in small lifts. Compact each
lift before the next one is placed. Ensure that
externally mounted insulation, drainage material,
dampproofing or waterproofing membranes are
not damaged.
FOUNDATION INSULATION
Foundation (basement) walls are required to
be insulated if they enclose conditioned space.
Basement floors with radiant heating must be
insulated underneath. The levels of insulation
required are determined by the climate zone in
which the house is built. See Chapter 5 for more
detailed information.
Foundations can be insulated on the interior or
the exterior of the building. Foundation walls
enclosing conditioned space should be insulated
FOOTINGS AND
FOUNDATIONS FOR
CRAWL SPACES
Crawl spaces are enclosed spaces between
the underside of a floor assembly and the
ground below, where the clearance is less than
the minimum 2 m (6 ft. 6 in.) required for a
basement and less than 25 per cent of their area
above ground is open to the outdoors. Crawl
spaces are often used to give access to ducts,
pipes, cables and other utilities and can be heated
(conditioned) or unheated (unconditioned). If a
crawl space is unheated, it is essential to have an
effective air barrier between the conditioned and
unconditioned space.
As for other types of foundations, footings for
crawl spaces must be placed at a depth below
grade determined by soil conditions and frost
penetration (see Table 3 on p. 265). Footing sizes
are generally the same as those used to support
basement walls. Crawl space walls may be built
86
CHAPTER 7
Footings, Foundations and Slabs
GARAGE FOUNDATIONS
Foundations for garages are usually concrete
or masonry. Concrete slab-on-ground or
preserved wood foundations are also options.
The minimum depth below grade for a garage
foundation attached to a house should not be
less than that shown in Table 3 (p. 264).
If fill is required below the floor, use compacted
granular material to avoid settlement after the
floor is placed and loads applied. The concrete
floor should be at least 75 mm (3 in.) thick.
Provide an airtight curb or partition at least
50 mm (2 in.) high at the edges of the slab
adjacent to interior space, and slope the garage
floor to the outdoors.
Place and cure concrete garage floors the same
way as basement floor slabs. Provide control
joints so that the concrete segments are similar
in size. For a single car garage, one control joint
dividing the floor into two roughly square
segments should be sufficient.
The foundation walls should not be less than
150 mm (6 in.) thick and should extend at least
150 mm (6 in.) above grade.
Sill plates should be anchored to the foundation
wall or slab with anchor bolts spaced not more
than 2.4 m (8 ft.) apart and with at least two
bolts in each sill piece. Extra anchors may be
required at the side of the main door and in
areas with high earthquake or wind exposure.
87
CHAPTER 7
Footings, Foundations and Slabs
Energy Efficiency
Resource Efficiency
RELATED PUBLICATIONS
CAN/CSA Standard O80 Series-08: Wood Preservation,
Canadian Standards Association
CAN/CAS Standard S406-92 (R2008): Construction of Preserved Wood Foundations,
Canadian Standards Association
CSA Standard O322-02 (R2007): Procedure for Certification of Pressure-Treated
Wood Materials for Use in Preserved Wood Foundations,
Canadian Standards Association
Permanent Wood Foundations,
Canadian Wood Council (product No. PWPD-06-E)
88
CHAPTER 8
89
CHAPTER 8
Framing the House
PLATFORM FRAMING
Platform construction is the most common
method for framing a house. The floor platform
is built first and the walls for each story are added
above each floor. Prefabricated walls can be
assembled on the floor platform, or walls can
be built horizontally on top of the floor and
then be tilted into place without using heavy
lifting equipment. The bottom and top plates,
which are an integral part of the wall framing,
provide fire blocks at the floor and ceiling and
also nailing support for wall sheathing and
interior finish.
BALLOON FRAMING
Balloon framing was common up to the
early part of the 20th century and is now
used only occasionally. Unlike platform framing,
the studs used for exterior and some interior
walls are continuous, passing beyond the floors
to the top plates that support the roof framing.
Floors are supported by ribbon boards inset into
the wall studs.
Unlike platform construction that provides fire
blocking at each wall-floor junction, fire blocks
must be specifically added to balloon frame
construction to prevent fire from spreading from
one floor to the next through the wall cavity.
Because there are fewer horizontal members
(rim joists and wall plates), there is less vertical
shrinkage with balloon framing compared to
platform framing.
In some two-storey houses, the intermediate
load-bearing wall in an otherwise platformframed house is balloon-framed to provide
convenient passage for heating ducts and pipes.
ADVANCED FRAMING
TECHNIQUES
Consider using advanced framing techniques
(AFT), also referred to as optimum value
engineering, to reduce the amount of wood
framing used in construction by eliminating
wood where it is structurally unnecessary, reduce
the amount of site-generated construction waste,
improve the thermal resistance of the building
envelope and reduce construction costs. AFT
requires careful coordination of the location of
roof, floor and wall framing members. Advanced
framing situates trusses, rafters or roof joists and
floor framing members directly over load-bearing
studs so that a single top plate can be used. With
AFT, cripples and jack studs underneath lintels
may be eliminated especially when the location
of door and window openings in the exterior
wall is coordinated with modular stud spacing
and use window sizes that fit between the studs,
and replaced with metal hangers, where larger
openings are located in exterior loadbearing
walls. For non-loadbearing exterior walls, cripples
and jack studs may be removed as they serve no
structural purpose and occupy space that could
otherwise be filled with insulation.
STRUCTURAL STRENGTH
The combination of dimension lumber or
engineered wood and wood panel sheathing
gives wall, floor and roof assemblies the strength
to resist vertical loads (snow, occupants and
contents) and horizontal loads (wind and
earthquake). Partitions, closets and finishes
such as gypsum board (drywall) also add rigidity.
Where additional strength is required because
of a high risk of exposure to earthquake or
wind, the floors, walls and roofs can be made
stronger by using thicker sheathing panels
and by placing the fasteners closer together.
90
CHAPTER 8
Framing the House
RESISTANCE TO LATERAL
LOADS DUE TO WIND AND
EARTHQUAKE
Different areas of Canada are subject to varying
risks of forces from winds and earthquakes. As a
result, all buildings must be built to resist these
lateral loads. The NBC Appendix C, Climatic
and Earthquake Information for Building
Design in Canada, provides wind pressures and
earthquake factors used to determine exposure
to wind and seismic (earthquake) loads for
buildings. NBC 9.23 provides requirements
for resisting lateral loads for low-rise buildings.
The requirements are based on three levels of
risk: low to moderate; high; and extreme.
Low to Moderate
Exposure Category
Buildings in the low to moderate exposure
category provide resistance to wind and
earthquake loads if they are of traditional
wood-frame construction comprised of exterior
sheathing, panel-type cladding or gypsum board
finish. If two or more of these options are chosen,
lateral load resistance will be increased. Of the
680 locations identified in NBC Appendix C,
671 and 630 locations fall into this category
for wind and earthquake exposure respectively.
This means that for most locations in Canada,
bracing requirements can be met by using
standard wood-framing materials and fastening
91
CHAPTER 8
Framing the House
Resource Efficiency
Reduce
Reuse
Review
Recycle
RELATED PUBLICATIONS
2010 National Building Code of Canada (Section 9.23, Part 4 and Appendix C),
National Research Council of Canada
Engineering Guide for Wood Frame Construction 2009,
Canadian Wood Council (publication no. EGWF-09-E)
92
CHAPTER 9
Floor Framing
93
CHAPTER 9
Floor Framing
sill plate
12 mm (12 in.) clearance if beam
is untreated and the beam bottom
is at or below grade all around or
beam end preservative-treated
at or below grade
separate wood beams installed less
than 150 mm (6 in.) above grade from
concrete with dampproofing material,
such as 0.155 mm (2 mil) polyethylene
89 mm (312 in.) minimum bearing
clear span
steel or wood column
94
CHAPTER 9
Floor Framing
wood joist
toenail
metal or wood column
95
CHAPTER 9
Floor Framing
FOUNDATION WALL-FLOOR
CONNECTION
There are two methods of wall and joist
connection used in platform framing: the sill-plate
method and the joist-embedded method.
Sill-Plate Method
The sill-plate method is the most common
form of connection and can be used with either
concrete or concrete block foundation walls.
It consists of a wood sill plate anchored to the
steel beam
joists connected by 38 x 38 mm (2 x 2 in.)
splices with at least 12 mm ( in.) space
between the splice and the beam
joist
alternatively, the joists may be supported
on a minimum 38 x 38 mm (2 x 2 in.) wood
plate bolted through the web of the beam
96
CHAPTER 9
Floor Framing
finish flooring
subfloor
sheathing membrane
rigid insulation over 2 4 framing
wall plate
200 mm (8 in.) minimum
bottom sill plate
anchored to foundation
floor joist toenailed to sill plate
continuous header
12 mm (12 in.) air space
if rim joist is untreated
97
CHAPTER 9
Floor Framing
Joist-Embedded Method
The joist-embedded method is used rarely,
and only with cast-in-place concrete foundation
walls. Beams, joists and headers are positioned
before the concrete is placed. Support the floor
framing temporarily on the inside concrete form
and use wedges to level the framing. Place filler
pieces between the floor joists and along the
end walls to retain the fluid concrete between
the joists.
rigid insulation
over 2 4 framing
wall stud
wall sheathing
sheathing membrane
subfloor
masonry veneer
air space
base flashing
150 mm (6 in.) minimum
12 mm (12 in.) air space if
the wood is untreated and
located at or below grade
floor joist toenailed to sill plate
dampproof course under sill
when less than 150 mm (6 in.)
above finished grade
continuous header
sill plate anchored to foundation
anchor bolt
98
CHAPTER 9
Floor Framing
FLOOR JOISTS
Joists are selected to meet strength, deflection
and vibration requirements on which the joist
selection tables are based (Tables 20 and 21
on pp. 285-286). The spans in the tables are
rim joist
header
floor joist
concrete foundation
brick veneer
header
sheathing membrane
lapped over flashing
metal flashing
floor joist
concrete foundation
99
CHAPTER 9
Floor Framing
adequate joist
bearing length
correct span
distance
squash blocks to
transfer point loads
safe installation
bracing or sheathing
correct placement and
sizing of holes in webs
web stiffeners
(where required)
to transfer floor loads
100
CHAPTER 9
Floor Framing
63 Floor framing
panel joint over joist
joist under partitions
parallel to joists
joists lapped over beam
blocking
floor joists toenailed to sill plate
cross-bridging
continuous wood strapping
sub floor nailed or screwed
to joists (field-gluing will
improve floor performance)
101
CHAPTER 9
Floor Framing
64 Framing for floor openings where double headers and double trimmers
are used
first header
second header
first trimmer joist
length of opening
102
CHAPTER 9
Floor Framing
Floor Performance
The floor joist span tables incorporate vibration
criteria. The tables recognize that some floor
constructions are more bouncy or springy
than others. Therefore, by adding blocking or
increasing subfloor thickness, floors will be less
springy or bouncy and floor joist spans may
be increased. Alternatively, engineered wood
products such as laminated veneer lumber joists,
wood I-joists and parallel-chord trusses may
be used, but vibration criteria must be also be
considered for these engineered products.
SUBFLOOR
Plywood, OSB or tongue-and-grooved lumber
no wider than 184 mm (8 in. nominal) is
typically used for subflooring. Minimum
thicknesses for subflooring are shown in
Table 22 (p. 287).
Plywood and OSB are often used as subflooring
under wood-strip flooring or as a combination
subfloor and underlay for resilient flooring
or ceramic tile. When used as a combination
subfloor and underlay, the side joints must
be supported on blocking at least 38 38 mm
(2 2 in. nominal) fitted between the joists
unless the panels have tongue-and-groove edges.
103
CHAPTER 9
Floor Framing
FLOOR FRAMING
AT PROJECTIONS
Floor joists sometimes project beyond the
foundation or framed wall to provide support
for a bay window or additional floor space in
the upper rooms. The cantilevered portion of
the floor framing should not exceed 400 mm
(16 in.) for 38 184 mm (2 8 in.) joists and
600 mm (24 in.) for larger joists (Figure 65).
In either case, this projection should not carry
loads from additional floors. If the cantilevered
floor joists are to carry additional loads, they must
104
CHAPTER 9
Floor Framing
Selection
Conditions
5 38 235 mm (5 2 10 in.) or
4 38 286 mm (4 2 12 in.)
interior support
built-up beam
+ b2
a2
beam span
supporting column
105
CHAPTER 9
Floor Framing
Selection
Conditions
106
CHAPTER 9
Floor Framing
RELATED PUBLICATIONS
Canadian Span Book 2009,
Canadian Wood Council (publication no. SB00-09-E)
Engineering Guide for Wood Frame Construction 2009,
Canadian Wood Council (publication no. EGWF-09-E)
107
CHAPTER 10
Wall Framing
108
CHAPTER 10
Wall Framing
stud toenailed to
bottom plate
top plates at
corners and load
bearing partitions
lapped and nailed
or tied with a metal
plate fastened to
the top plates
temporary brace
stud and jack stud
cripple/trimmer stud
window opening
lintel
Note: Where the lintel exceeds 3 m (10 ft.), the jack stud needs to be doubled on both sides of the opening.
109
CHAPTER 10
Wall Framing
PLATFORM FRAMING
This is a common framing method where each
floor serves a work platform for building and
erecting the walls for the next storey. End-nail
the top and bottom plates to each stud with two
nails at least 82 mm (314 in.) long. Apply wall
sheathing to the framing prior to erection
to eliminate the need for scaffolding for this
operation. Some types of sheathing such as
plywood and OSB will resist lateral loads
and keep walls square. Others such as rigid
glass-fibre, asphalt-coated fibreboard, polystyrene
or polyurethane board will not, and walls need
to be reinforced with diagonal wood or metal
bracing let into the studs (Figure 68).
Once a wall section is ready, rotate it into the
vertical position, add temporary braces and
nail the bottom plates to the subfloor and floor
framing members (Figure 68). The braces should
have their larger dimension on the vertical and
allow the vertical position of the wall to be
adjusted so that it is plumb.
110
CHAPTER 10
Wall Framing
corner studs
three-stud
corner
bottom plate
two-stud
corner
subfloor
gypsum
board clip
end joist
insulation
sill plate
foundation
interior stud
attached to stud
polyethylene strip
partition stud
insulation in spaces
between studs
interior stud
attached to
blocking
bottom plate
subfloor
end joist
interior stud
attached after
drywall installation
sill plate
foundation
111
CHAPTER 10
Wall Framing
71 Support for ceiling finish where ceiling joists run parallel to a partition
38 x 89 mm (2 x 4 in.) blocking
nailed to ceiling joists
ceiling joist
38 x 140 mm (2 x 6 in.) nailing support
air barrier tab for connection
to the ceiling air barrier system
(may also be installed between top
platesnot required between floors)
plate
stud
floor joist
wood nailing support for
interior finish
end joist
plate
112
CHAPTER 10
Wall Framing
113
CHAPTER 10
Wall Framing
BALLOON FRAMING
For balloon-framed construction, both the
studs and first-floor joists rest on the foundation
sill plate (Figure 74) and an intermediate beam
or bearing wall. Studs are toe-nailed to these
supports with at least four 63 mm (2 in.) nails;
the joists in turn are nailed to the studs with
at least two 76 mm (3 in.) nails. When lumber
subfloor is laid diagonally, blocking is required
between the joists at the wall lines to support the
ends of the boards.
Upper-floor joists bear on a ribbon board not
less than 19 89 mm (1 4 in. nominal) that has
been let into the studs, and the joists are nailed to
the studs. The end joists parallel to the exterior
walls on all floors are also nailed to the studs.
19 x 89 mm (1 in. x 4 in.)
ribbon let-in
stud
alternative
corner
114
CHAPTER 10
Wall Framing
STRUCTURAL INSULATED
PANELS (SIPS)
corner connection
rough
opening
header panel
115
CHAPTER 10
Wall Framing
76 Platform framing
Conditions
First floor interior wall studs support a
second storey and an attic that is not served
by a staircase (that is, without storage).
All studs are 2.36 m (7 ft. 9 in.) long.
Selection
Use Table 25 (p. 290).
Acceptable wall stud sizes for this
application include:
2.36 m
(7 ft. 9 in.)
38 64 mm (2 3 in.) spaced at
400 mm (16 in.) on centre, or
38 89 mm (2 4 in.) spaced at
600 mm (24 in.) on centre
Note: In accordance with the National Building
Code, the metric spacing of wood framing
members is expressed as a soft conversion
from the actual imperial dimensions. For example,
spacing of 12, 16 and 24 inches on centre is
converted to 300, 400 and 600 mm. on centre,
respectively. In order to suit the imperial sizes
of common 1 220 2 440 mm (4 8 ft.) panel
116
CHAPTER 10
Wall Framing
Resource Efficiency
117
CHAPTER 11
118
CHAPTER 11
Ceiling and Roof Framing
PITCHED ROOFS
Prefabricated roof trusses are most often used
for framing residential roofs. Rafters framed on
site are sometimes used. Of the pitched roofs,
the gable roof is the simplest to construct.
Other pitched configurations, such as a hip
or L-shape roof, can also be framed with
trusses (Figure 77).
ridge
valley trusses
roof sheathing
gable end
girder truss
common trusses
double wall plates
Note: For clarity, some structural members of some of the trusses have been omitted,
and roof sheathing appears continuous.
119
CHAPTER 11
Ceiling and Roof Framing
king-post
Howe
Fink or W
mono-pitch
parallel chord
scissor truss
provide truss
anchors as
requested by
manufacturer
or by code
mansard
120
CHAPTER 11
Ceiling and Roof Framing
Note: Gable ends are normally sheathed prior to installation of end braces.
Plan View
lateral brace
top chord
ridge line
diagonal brace
nailed to
webrepeat at
approximate
6 m (20 ft.)
intervals as
required by truss
manufacturer
lateral bracing
End Elevation
38 x 89 mm
(2 x 4 in.) web
bracing as
required by truss
manufacturer
Side Elevation
sheathing
blocking
lateral brace
diagonal forms
braced bayrepeat
at both ends and at
approximate 6 m (20 ft.)
intervals as required
by truss manufacturer
ceiling
121
CHAPTER 11
Ceiling and Roof Framing
Flat
Monopitch
Gable
Hip
Gambrel
Mansard
122
CHAPTER 11
Ceiling and Roof Framing
Gable roof
ridge board
rafter
collar brace
collar tie
gable end stud
ceiling joist
top wall plate
Hip roof
123
CHAPTER 11
Ceiling and Roof Framing
ridge beam
rafter
exterior wall
knee wall with top and bottom plates and
stud in line with each ceiling joist and rafter
struts at 1.2 m (4 ft.) o.c.
ceiling joists lapped directly
above interior load-bearing wall
85 Doubled ceiling joists and stub joists used where a hip rafter reduces clear
space near the end wall
jack rafter
124
CHAPTER 11
Ceiling and Roof Framing
studs in load-bearing
wall located directly
under each rafter
38 mm (2 in.) thick splice plate
interior bearing wall
roof rafters notched and bearing
directly on top plate of exterior wall
continuous nailer and soffit supports
ceiling joists extend beyond the exterior
wall and are nailed to the rafters and
toe-nailed to the double wall plate
wall sheathing
exterior wall
125
CHAPTER 11
Ceiling and Roof Framing
87 Framing at a valley
valley rafter
jack rafter
common rafter
top plate
corner wall studs
126
CHAPTER 11
Ceiling and Roof Framing
Gable-End Framing
and Projections
After roof framing members have been
installed, the gable-end studs are nailed
in place. Studs in unfinished attics can be
placed with the wide face parallel to the wall.
Cut the ends of the studs to fit the angle of
the rafter and toenail them to the wall plate
and to the underside of the rafter with at
double header
jack rafter
double rafter
joist hangers
valley rafter
side stud
size window to allow for
proper flashing, detailing
and finishing of roofing
roof sheathing applied prior
to construction of dormer
127
CHAPTER 11
Ceiling and Roof Framing
128
CHAPTER 11
Ceiling and Roof Framing
Low-Slope Roofs
129
CHAPTER 11
Ceiling and Roof Framing
baffle
perforated soffit
pre-finished fascia
airflow
130
CHAPTER 11
Ceiling and Roof Framing
Gable vent
wind flow
airflow
airflow
131
CHAPTER 11
Ceiling and Roof Framing
Selection
Conditions
94 Ceiling joists
132
CHAPTER 11
Ceiling and Roof Framing
Selection
Conditions
95 Roof rafters
3
1
133
CHAPTER 11
Ceiling and Roof Framing
Conditions
Roof slope is 1 in 3.
Selection
Use Table 29 (p. 295).
Acceptable roof joists include:
38 235 mm (2 10 in.) at
400 mm (16 in.) on centre.
38 286 mm (2 12 in.) at
600 mm (24 in.) on centre.
Note: The roof joists must also be deep enough
to accommodate the required level of insulation.
96 Roof joists
3
1
134
CHAPTER 11
Ceiling and Roof Framing
Affordability
When planned in advance, attic space can
be converted to high-quality living space.
This is economical because it provides
additional space without increasing the
building footprint and makes use of an
existing roof. Consider these factors when
planning attic rooms:
Resource Efficiency
Prefabricated roof trusses are widely used
for residential roof framing. Trusses use an
efficient arrangement of select lumber and
metal plates to provide long spans and reduce
the amount of wood required as compared
with framing with lumber rafters and joists.
They provide the following advantages:
135
CHAPTER 12
ROOF SHEATHING
136
CHAPTER 12
Roof Sheathing and Coverings
Closed method
roof boards
joint
rafter
ceiling joist
plate
Note: For areas exposed to high wind and earthquake forces, lumber roof sheathing must be installed diagonally.
Canada Mortgage and Housing Corporation
137
CHAPTER 12
Roof Sheathing and Coverings
EAVE PROTECTION
Eave protection is achieved by installing a
membrane along the edge of the roof to
prevent water from entering the roof. It is
not required over unheated garages and
porches, on roofs with a slope of 1:1.5 or
greater or in regions with 3,500 or fewer
heating degree-days. Eave protection should
extend at least 900 mm (36 in.) up the roof
to a point at least 300 mm (12 in.) inside the
inner face of the exterior wall. Eave protection
is installed under the shingle starter course
and is most often a self-adhering bituminous
or roll roofing membrane.
During cold weather, heat loss through the
ceiling insulation combined with sun exposure
may provide enough heat to melt the snow
on a roof but not on the projecting eaves.
Water from the melting snow can freeze and
form ice dams at the eavestrough and roof
50 mm (2 in.)
clearance around chimney
header
rafter
roof sheathing
valley
ridge board
ceiling joist
plate
stud
138
CHAPTER 12
Roof Sheathing and Coverings
snow
trapped water backs up through
the roofing membrane
thin ice slab under snow
melted snow running down
underside of sheathing
heat loss or outdoor
temperature melts snow
ice
ice in eavestrough
inside face of wall
insulation
Eave protection
139
CHAPTER 12
Roof Sheathing and Coverings
ROOF COVERINGS
The roof covering should be installed as
soon as the sheathing is in place to keep
the building dry and to provide durable,
water-resistant protection.
The choice of roofing materials may be influenced
by cost, appearance, local code requirements or
local preferences. Asphalt shingles are commonly
used on pitched roofs. Prefinished metal,
galvanized steel or aluminum roofing is also
common in some regions. At normal roof pitches,
metal roofs will generally shed snow, a desirable
characteristic in heavy snowfall areas. Roll roofing,
wood shingles, hand-split shakes, sheet metal
and concrete or clay tile are also used. Built-up
roofing with a gravel topping or cap sheet is
usually used for low-slope roofs.
140
CHAPTER 12
Roof Sheathing and Coverings
Wood Shingles
Western red and white cedar are the principal
species of wood used for shingles because their
heartwoods have high decay resistance and low
shrinkage (they may also be preservative-treated).
Other species are also used for shingles but should
be preservative-treated. Wood shingles commonly
for houses are No. 1 and No. 2 grade. The width
of wood shingles varies between a maximum
width of 350 mm (14 in.) and a minimum
width of 75 mm (3 in.).
141
CHAPTER 12
Roof Sheathing and Coverings
roof sheathing
two nails per shingle
20 mm (1316 in.)
edge distance to nails
wood shingles
exposure
40 mm (1916 in.) lap
6 mm (14 in.) space between shingles
fascia board
first shingle course (double)
project shingles 12 mm (12 in.) for drip
142
CHAPTER 12
Roof Sheathing and Coverings
Shakes
Cedar hand-split shakes must not be less
than 450 mm (18 in.) long and 100 mm
(4 in.) wide, and no wider than 350 mm
(1334 in.). The butt thickness should be
between 9 and 32 mm (38 and 114 in.)
(Figure 103).
Shakes may be applied over spaced or closed
roof sheathing. When spaced sheathing is
used (Figure 98), apply 19 89 mm (1 4 in.
nominal) or wider strips on centre equal to the
weather exposure at which the shakes are to be
laid, but never more than 250 mm (10 in.).
Closed roof sheathing is recommended for areas
where wind-driven snow conditions prevail.
143
CHAPTER 12
Roof Sheathing and Coverings
Built-up Roofs
Built-up roof coverings should be installed by
specialized roofing installers. A built-up roof
may have three or more layers of roofing felt.
Each layer, including the final layer, is sealed
with tar or asphalt. The surface is then covered
with gravel (embedded in the asphalt or tar) or
with a cap sheet. This covering provides ballast
against wind uplift and protection from the sun.
Asphalt shingles
nail
prevailing wind
Wood shingles
144
CHAPTER 12
Roof Sheathing and Coverings
siding
sheathing membrane
50 mm (2 in.) minimum lap
membrane flashing
cant strip
roof sheathing
built-up roofing
Junction of built
up roof and wall
covered with siding
fascia board
Eave flashing
and drip
145
CHAPTER 12
Roof Sheathing and Coverings
Eave starter
Valley
Ridge cap
Cottage hip
146
CHAPTER 12
Roof Sheathing and Coverings
Energy Efficiency
147
CHAPTER 13
148
CHAPTER 13
Wall Sheathing and Exterior Finishes
Horizontal application
window opening
nails
2-3 mm (18 in.) space between sheets
edge nail 150 mm (6 in.) o.c.
nail 300 mm (12 in.) o.c.
foundation
149
CHAPTER 13
Wall Sheathing and Exterior Finishes
Horizontal application
joint
foundation
Diagonal lumber
floor sheathing
Diagonal application
stud
45
sheathing
joist
foundation wall
150
CHAPTER 13
Wall Sheathing and Exterior Finishes
SHEATHING MEMBRANE
The sheathing membrane forms part of
a second line of defence against the entry
of rainwater and may also be, in some
cases, a primary component of the air
barrier system. Since some moisture
may condense in the wall space in winter,
the sheathing membrane must be capable
of allowing it to diffuse outward to prevent
wood decay.
Several types of sheathing membrane are
commonly used in wood-frame construction:
EXTERIOR CLADDING
Aside from contributing to house appearance
and durability, exterior cladding is an important
part of the water penetration control strategy.
Common types of cladding are made of
metal, vinyl, hardboard, fibre-cement board
or lumber siding; panel siding made of plywood,
OSB, hardboard; wood shingles or shakes;
stucco; and masonry cladding such as brick
and stone.
Most siding can be affected by moisture and
must be kept at least 200 mm (8 in.) away from
the ground and at least 50 mm (2 in.) from an
adjoining roof surface. Methods of flashing
over window and door openings and between
different types of wall covering are described
in Chapter 14.
151
CHAPTER 13
Wall Sheathing and Exterior Finishes
Horizontal Application
Prepare the wall for cladding by applying the
sheathing membrane. In wet and humid coastal
climates, strapping (furring) is required to provide
a vented space (rainscreen) to facilitate drainage
and drying. Establish a level line around the
house for the starter strip, which is normally
placed a minimum of 150 to 200 mm (6 to 8 in.)
above finished grade. Install all trim pieces for
corners, windows, doors and openings and starter
strips; and then apply the siding in successive
courses up to the underside of the soffit.
Laps of adjacent strips of siding should be
staggered more than 600 mm (24 in.) apart
and should all face in the same direction away
from the general viewing angle.
Vertical Application
Apply the sheathing membrane to prepare
the wall for cladding. Some types of metal
and vinyl siding can be applied directly over
the sheathing membrane. In locations that
require a rainscreen, the strapping (furring)
should be applied horizontally and spaced
according to the siding manufacturers
recommendations. Provide 10 mm (38 in.)
gaps between the butt ends of the strapping
to allow water behind the cladding to drain
downwards and out of the wall.
Bevel
Drop siding
lap
exposure
Tongue-and-groove
with V-joint
Board-on-board
152
CHAPTER 13
Wall Sheathing and Exterior Finishes
Hardboard Siding
Hardboard horizontal siding (Figure 110) is
made in a wide range of colours. It often has
splines for interlocking the panels and is installed
in a manner similar to metal and vinyl siding.
Some manufacturers require that their hardboard
siding be installed over furring.
Lumber Siding
Lumber siding should be sound and free of
knotholes, loose knots, checks or splits. Cedar
and pine are the most commonly used species.
It has also become more common to use
pressure-treated lumber for siding or wood
that has been factory-finished with stain or
paint. The finish should cover the front and
back surfaces of the siding to reduce water
absorption. At the time of application, the siding
should have moisture content similar to what
it will be exposed to, that is, between 12 and
18 per cent, depending on a regions humidity
and climate.
Rainscreen wall assemblies (Figure 110,
for example) are required in wet, humid
climates such as the coastal regions of Canada.
Horizontal Application
Bevel or feather-edge siding (see Figure 109)
is installed from the bottom up with the
bottom edge of the lowest course mounted on
a 6 mm (14 in.) thick furring strip. Overlap each
succeeding course at least 25 mm (1 in.) over
the lower course. Spacing for the siding should
be planned before the installation starts. Deduct
the minimum lap from the overall width of
sheathing
sheathing membrane
vertical furring strips
horizontal siding
metal starter strip
insect screen
153
CHAPTER 13
Wall Sheathing and Exterior Finishes
Nailing
154
CHAPTER 13
Wall Sheathing and Exterior Finishes
Vertical Application
Lumber siding that can be applied vertically
includes: plain matched boards; patterned
matched boards; square-edge boards covered
at the joints with a batten strip; or square-edge
boards spaced apart and covered with another
board. Vertical siding is usually 14.3 mm (916 in.)
thick. Boards should not be wider than 286 mm
(12 in. nominal). Vertical boards may be fastened
to 14.3 mm (916 in.) lumber sheathing, 12.5 mm
(12 in.) plywood or 12.5 mm (12 in.) OSB or
waferboard, or to horizontal furring strips.
The furring (strapping) should be at least
19 64 mm (1 3 in. nominal) lumber where
the framing is spaced not more than 400 mm
(16 in.) on centre or 19 89 mm (1 4 in.
nominal) lumber where the framing is spaced
not more than 600 mm (24 in.) on centre.
Butt joints in lumber siding should be cut at
45 degrees (mitred) and overlapped to prevent
the entry of water into the joint.
Plywood Panels
Plywood sheets acceptable for use as a cladding
material are made with a plain or grooved surface
and are usually applied vertically. The joints may
be V-grooved or flush or may be covered with
battens. Some products have a resin-impregnated
paper laminated to the face that provides a
smooth, moisture-resistant surface that resists
checking or splitting after painting or staining.
If a rainscreen is not required, plywood
cladding may be applied directly over the
sheathing membrane on unsheathed wall
framing. The minimum thickness used is
6 mm (14 in.) for stud spacing of 400 mm
(16 in.) on centre and 8 mm (516 in.) for
spacing of supports up to 600 mm (24 in.)
on centre when the face grain is installed at
Canada Mortgage and Housing Corporation
155
CHAPTER 13
Wall Sheathing and Exterior Finishes
Hardboard Panels
Hardboard is also produced in sheets with
a variety of finishes and may be applied over
sheathing or to unsheathed walls if a rainscreen
is not required. The minimum thickness of
sheets should be at least 6 mm (14 in.) for
supports that are not more than 400 mm
(16 in.) on centre. Fasten the panels to framing
members or sheathing with corrosion-resistant
Mitred corner
Metal corners
corner boards
siding
156
CHAPTER 13
Wall Sheathing and Exterior Finishes
Stucco Finishes
Stucco is a mixture of Portland cement and
well-graded sand, with hydrated lime or masonry
cement added to make the mixture more plastic
(Table 39 on p. 307). Other proprietary stucco
mixes are available. Their formulations will vary
depending on the manufacturer of the mix.
Usually applied in three coats (two base coats and
one finish coat), the stucco is held in place by
stucco mesh or wire lath. A variety of finish coats
are available, from standard coloured cement
finishes to textured acrylics. Acrylic finish coats
are often applied over conventional Portland
cement, with good results. It is important
that the chosen product be durable and
vapour-permeable.
Canada Mortgage and Housing Corporation
157
CHAPTER 13
Wall Sheathing and Exterior Finishes
Reinforcing
Stucco reinforcing (self-furring welded mesh
or fully primed or galvanized woven mesh)
is stretched horizontally over sheathing paper,
with the joints in the mesh lapped at least
50 mm (2 in.). Reinforce external corners by
extending the mesh from one side 150 mm
(6 in.) around the adjacent corner, or by vertical
strips of reinforcing that extend 150 mm (6 in.)
on either side of the corner.
Galvanized steel fasteners should be used
to hold the mesh in place such as 3.2 mm
(18 in.) diameter nails with heads that are about
11.1 mm (716 in.), or 1.98 mm (0.078 in.)
thick staples. Fasteners are spaced 150 mm (6 in.)
vertically and 400 mm (16 in.) horizontally, or
100 mm (4 in.) vertically and 600 mm (24 in.)
horizontally. Other fastening patterns may be
used, provided there are at least 20 fasteners per
square meter (2 fasteners per square foot) of the
Application
A layer of sheathing membrane, lapped 100
mm (4 in.) at the edges, must be applied over
the sheathing, and all openings must be flashed.
Apply the membrane carefully around window
openings and lap them correctly to ensure that
water does not enter at the window flanges.
Tar-saturated felts or papers should not be used
beneath the stucco but tar-impregnated felts or
paper may be used. The tar can bleed through
the stucco causing unsightly discolouration.
The base coat consists of two layers of stucco.
The first layer or scratch coat is applied in
a thickness of 6 mm (14 in.) that completely
embeds the wire lath or mesh. The scratch
coat surface must be scored or raked to provide
a bonding key for the second coat. Curing time
will depend on outdoor temperature and weather
conditions. Up to 48 hours of cure time is
recommended before the second coat is applied.
Just prior to adding the second coat, dampen
the base to ensure a good bond between the
coats. Apply the second coat at least 6 mm
(14 in.) thick and firmly trowel it into the scored
surface of the base.
The second coat should be moist-cured for at
least 48 hours and then left to dry for at least five
days before the finish coat is applied. The second
coat should be dampened to ensure a good bond
and the finish coat applied to a depth of at least
3 mm (18 in.).
In dry, warm weather, new stucco should be
kept damp to ensure proper curing. In cold
weather, each coat of stucco should be kept at a
temperature of at least 10C (50F) for 48 hours
after application.
158
CHAPTER 13
Wall Sheathing and Exterior Finishes
Masonry Veneer
When masonry veneer is used for cladding,
the foundation must include a supporting ledge
or offset wide enough to allow a space at least
wall stud
wall sheathing
insulation
air/vapour barrier
bottom plate
subfloor
floor joist
header joist
sill plate
anchor bolt
foundation
159
CHAPTER 13
Wall Sheathing and Exterior Finishes
160
CHAPTER 13
Wall Sheathing and Exterior Finishes
161
CHAPTER 13
Wall Sheathing and Exterior Finishes
improve appearance;
162
CHAPTER 13
Wall Sheathing and Exterior Finishes
Energy Efficiency
163
CHAPTER 14
Flashing
at roof-wall junctions;
at roof-chimney junctions;
at valleys in roofs;
164
CHAPTER 14
Flashing
Gravity
The building should have the following features
to deflect water that flows downward from the
pull of gravity:
Surface Tension
Surface tension allows water to flow along
the underside of a surface horizontally, and
even upward, in narrow spaces such as crevices.
In confined spaces, spacing horizontal surfaces
more than 9 mm (0.38 in.) apart will prevent
the adherence of water to the two surfaces, thus
allowing the water to drain away. A drip edge is
placed at points of discharge to break that surface
tension and allow water to drop by gravity.
Capillary Action
In porous materials such as concrete and brick,
water can be drawn into small-diameter openings
of less than 5 mm (0.20 in.) by capillary action
or wicking. The flashing joints should stop this
from occurring. The design of joints and upturns
must address this particular issue.
Kinetic Energy
Rain is often directed at flashings with
high velocity and significant horizontal
motion. On the upper locations of buildings,
TYPES OF FLASHING
Many types of flashing are available, as each
location vulnerable to rain penetration has
different flashing design needs. The most
common types are described below and have
been named to describe how they function
and where they are located.
Base Flashing
When a roof intersects with a wall or another
roof penetration, such as a plumbing vent,
the roofing system should be turned up to
make the junction watertight. The part of
the roofing that is turned up is generally
known as a base flashing. It may be made
165
CHAPTER 14
Flashing
Counter Flashing
counter
flashing
base
flashing
counter flashing
base flashing
cant
saw cut
counter flashing
base flashing
cant
roof
roof
166
CHAPTER 14
Flashing
Through-Wall Flashing
Cap Flashing
cavity
Dampproof Flashing
flashing
cavity
dampproofing
flashing (flexible,
self-adhering
rubberized
asphalt
membrane)
weep holes
through wall
flashing
exterior finish
sheathing
167
CHAPTER 14
Flashing
Valley Flashing
A valley flashing should be installed where
two roof slopes intersect to form a valley.
Open valleys leave the middle of the flashing
exposed (see Figure 123) and must be flashed
with one layer of sheet metal at least 600 mm
(24 in.) wide, or with two layers of roll roofing
installed over continuous sheathing. The bottom
layer is Type S smooth roll roofing or Type M
mineral surface roofing (mineral surface down),
at least 457 mm (18 in.) wide. Centre this
layer on the valley and fasten along the
edges with nails spaced 400 to 450 mm
(16 to 18 in.) apart.
Apply a 100 mm (4 in.) band of roofing cement
along the edge of the bottom layer. Then apply
a second strip of Type M mineral surface roll
roofing approximately 914 mm (36 in.) wide
over the first layer (mineral surface up). Fasten
the top layer along the edges with enough nails
to hold it in place until the shingles are applied.
The roof shingles stop 100 to 150 mm (4 to
6 in.) from the centre of the valley, with the
distance increasing from top to bottom.
shingle-lapped,
stepped
counter flashing
cut saw
shingled
stepped
base flashing
slo
pe
do
w
168
CHAPTER 14
Flashing
end dam
stepped base flashing (only
two sections shown for clarity)
shingles lap over flashing. Flashing
interwoven with shingle courses
minimum overlap 100 mm (4 in.)
minimum overlap 75 mm (3 in.)
solder or
install sealant
at all joints
169
CHAPTER 14
Flashing
Drip Flashing
Drip flashings intercept moisture that has entered
behind the cladding and direct it to the outside,
as well as redirect water flowing down the face
of the wall to prevent it from dripping down
on the materials below. A drip flashing should be
inserted between two different siding materials
(for example, siding above stucco) or between
different materials and components. To prevent
water from entering the joint, a preformed drip
should extend from behind the siding out over
the stucco to a drip at the outside edge (Figure 9).
saddle required by
code where width of
upper side of chimney
exceeds 750 mm (30 in.)
one-piece saddle
rubberized asphalt sheet
installed on sheathing
before installation of
metal flashings
170
CHAPTER 14
Flashing
FLASHING PERFORMANCE
REQUIREMENTS
The following performance requirements should
be considered when materials to be used as
flashing are selected:
Water Barrier
The flashing assembly that includes materials
and joints must shed water without allowing
leakage. The ability of the flashing to seal and
be detailed to avoid leakage is fundamental.
Creating an effective and durable joint seal is
often difficult. It is good practice to provide
a secondary, continuous flexible membrane
flashing under jointed materials such as brick,
stone or sheet metal.
Movement Capability
The flashing must be able to accommodate
differential thermal and structural movements.
As a result, it must either be made of a flexible
material or have joints designed to accommodate
movement such as thermal expansion and
Terminations
Terminations should be formed into sharp
breaks and to be sufficiently rigid at points of
discharge to adequately project water away from
materials below.
Durability
The flashing must be tough enough to resist
physical damage during construction, as well
as normal wear, which may be related to
the environment and building maintenance
activities. Other factors to be considered
include deterioration from corrosion, metal
incompatibility and galvanic action, deterioration
due to exposure to ultraviolet (UV) light, extreme
(hot and cold) temperatures, freezing water and
fatigue due to movement.
For more information on durability, consult
the CSA Standard S478-95: Guidelines on
Durability in Buildings. In general, the service
life of flashings must be equal to or more than
that of the wall system or roof system at locations
where maintenance or replacement of flashings
would be uneconomical.
Compatibility
Flashings along with their primers and sealants
must all be chemically compatible with adjacent
materials. Avoid contact between dissimilar
metals, as this can lead to galvanic corrosion
when the metals are moist. Water acts as the
electrolyte, and dissimilar metals as electrodes.
Alkaline concrete and mortar aggressively
attack materials such as aluminum and
copper. These materials should be protected
from contact with concrete or mortar by the
171
CHAPTER 14
Flashing
Buildability
Creating a flashing detail that is easy to build will
greatly increase the likelihood that the flashing
will be built to perform acceptably. Ask yourself
the following questions:
Maintenance
Besides durability, future maintenance of the
flashing must be considered. Materials or joint
sealants with limited service lives should be
avoided if the flashings are not accessible for
replacement. Metal flashings built into concrete
or masonry cannot be removed to allow for
inspection or repair of the materials underneath.
This should be considered when selecting
materials and details for flashings. The flashings
and sealants should be inspected annually,
particularly in areas with the greatest exposure
to water and sunlight.
RELATED PUBLICATIONS
CSA Standard S478-95: Guidelines on Durability in Buildings,
Canadian Standards Association
172
CHAPTER 15
173
CHAPTER 15
Windows, Exterior Doors and Skylights
AIRTIGHTNESS, WATER
RESISTANCE AND WIND
LOAD RESISTANCE
ENERGY RATING
174
CHAPTER 15
Windows, Exterior Doors and Skylights
MEANS OF EGRESS
0.35 m2
(3.8 ft2) min.
unobstructed
area
Horizontal slider
175
CHAPTER 15
Windows, Exterior Doors and Skylights
WINDOWS
Window Types
Many types of windows have different
characteristics (Figure 128) along with their own
advantages and disadvantages. Common window
terms are shown in Figure 129.
Fixed windows cannot be opened and are
generally the least expensive. Though they
usually offer the best level of energy efficiency
and resistance to forced entry, fixed windows
do not provide natural ventilation and cannot
serve as a means of egress in case of fire.
Single- or double-hung windows open
vertically. A single-hung window has only one
operable sash (usually the bottom unit) and a
128 Common window types
Interior
Casement
Slider
Hopper
Exterior
sash
Awning
Tilt-and-turn
insulating glass
unit (glazing)
sill
Single-hung or Double-hung
176
CHAPTER 15
Windows, Exterior Doors and Skylights
Low-Emissivity Coatings
Window Performance
Gas Fills
177
CHAPTER 15
Windows, Exterior Doors and Skylights
Edge Seals
The thermal efficiency of a sealed glazing
unit can be significantly improved by using
a low-conductivity edge spacer between panes
of sealed glass units. Aluminum was commonly
used for window spacers but resulted in cold
areas around the edges of glazing units.
Plastic, silicone and glass fibre spacers are
now used to reduce thermal conductivity
at the glass edges.
Appearance
Thermally-Efficient Frames
Window frames are typically constructed of
aluminum, vinyl (polyvinyl chloride, or PVC),
wood or fibreglass. Each of these materials
has unique properties suited for window
frame construction, but differ in terms of
thermal performance. Aluminum is very
conductive (1,000 times greater than vinyl,
wood or fibreglass) and, therefore, performs
poorly from a thermal efficiency standpoint.
Aluminum frames must be thermally broken
using low-conductivity materials such as PVC
or nylon, which improve the performance of
the frame significantly. Frames constructed
of wood, PVC and fibreglass all have similar
low-conductivity properties Further improvements
can be made in PVC and fibreglass by filling the
voids and airspaces in the frames with insulation.
While the frames may only make up a small
portion of the overall window area, the thermal
performance of a window is significantly
influenced by the frame selection.
Window Selection
The following list shows window selection factors:
Cost
Warranty
Energy performance
Window Installation
Windows are usually installed after the
house framing and roof covering have been
completed. Windows should arrive just in
time for installation. If they are delivered early,
store them upright in a secure, dry and level
area in their original packaging with any
temporary bracing left in place. Screens are
susceptible to damage and should be removed,
labelled and stored until construction is complete.
Prior to installation, review the manufacturers
installation instructions, and ensure that all of
the proper tools, fasteners and materials are
available. Install windows plumb and level within
the rough opening using shims to position and
temporarily secure them.
Improper window installation can result in
water and air leakage problems and poor
functioning of operable units. Correct window
installation includes lapping and sealing the
water-impermeable sheathing membrane to
the window to form a continuous second
178
CHAPTER 15
Windows, Exterior Doors and Skylights
5. install overlapping
WI membrane
D
8. install window,
shims and insulation
9. install head flashing
10. install and lap wall
sheathing membrane
11. lap sheathing
membrane
above opening
E
12. install wood
furring
13. install metal
drip edge
14. install siding
15. install backer rod
and exterior and
interior sealants
179
CHAPTER 15
Windows, Exterior Doors and Skylights
180
CHAPTER 15
Windows, Exterior Doors and Skylights
EXTERIOR DOORS
Exterior doors, like windows, affect the
appearance of a dwelling and are often
selected on the basis of style and finish.
Most manufactured exterior doors come
as manufactured units pre-hung in their
frames and ready for installation within a
rough opening.
Exterior doors are usually manufactured of
wood, steel, plastic or fibreglass. Wood doors
are normally solid, while other types consist
of inner and outer structural panels filled
with insulation and are more energy-efficient.
However, wood doors have proven performance
and a traditional appearance that have
contributed to their popularity.
Main doors should not be less than 45 mm
(134 in.) thick. They should be at least 810 mm
(32 in.) wide and 1.98 m (6 ft. 6 in.) high.
pre-drilled
lockset holes
hinge
threshold
181
CHAPTER 15
Windows, Exterior Doors and Skylights
Glazing
Glazing in exterior doors should be thermally
efficient, and depending on their size and
location, may also have to be tempered for
added safety. Glass sidelights greater than
500 mm (20 in.) wide that could be mistaken
for a door and glass in storm or sliding doors
is required to be safety glass. Sidelights must
be double-glazed. When no glazing is provided,
a door viewer is required for security purposes.
As is the case for windows, the amount of
glazing in side doors near property lines may
be restricted depending on the distance to the
property line.
25 mm (1 in.)
deadbolt projection not
less than 25 mm (1 in.)
182
CHAPTER 15
Windows, Exterior Doors and Skylights
SKYLIGHTS
Skylights are windows designed and
manufactured for installation in a roof assembly.
They must be installed carefully because they
are exposed to severe climatic conditions and
their remote location makes them difficult to
183
CHAPTER 15
Windows, Exterior Doors and Skylights
Energy Efficiency
RELATED PUBLICATIONS
AAMA/WDMA/CSA 101/I.S.2/A440-11 Standard: NAFSNorth American Fenestration
Standard/Specification for windows, doors and skylights,
Canadian Standards Association
CSA A440S1-09: Canadian Supplement to AAMA/WDMA/CSA 101/I.S.2/A440,
NAFSNorth American Fenestration Standard/Specification for windows,
doors, and skylights,
Canadian Standards Association
184
CHAPTER 16
EAVE PROJECTION
The eave overhang gives some protection to the
wall. Soffits are usually clad with prefinished
perforated metal or vinyl panels (Figure 136).
These are low maintenance and provide ample
area for venting roof spaces without permitting
insects to enter the space. A narrow eave
projection is sometimes used on roofs with
steep slopes. Soffits should not be used to
vent rainscreen wall spaces.
Plywood was once commonly used for soffits
and still is at times. Apply 6 mm (14 in.)
sanded plywood nailed at 150 mm (6 in.)
on centre along the edges and 300 mm (12 in.)
185
CHAPTER 16
Exterior Trim and Millwork
roof sheathing
fascia board
pre-finished fascia
vented soffit
roof sheathing
fascia board
pre-finished fascia
vented soffit
roof sheathing
fascia board
pre-finished fascia
vented soffit
186
CHAPTER 16
Exterior Trim and Millwork
fascia
plywood
soffit at rake
plywood
soffit at eave
fascia
plywood
soffit at eave
plywood
soffit at rake
fascia
plywood soffit
fascia
vinyl or
metal soffit at eave
vinyl or
metal soffit at rake
187
CHAPTER 16
Exterior Trim and Millwork
sheathing membrane
siding
shim
door jamb
caulking
sloped doorsill
water-impermeable
sill membrane
Resource Conservation
188
CHAPTER 17
Stairs
STAIRWAY DESIGN
Stairs may be site built but are most often factory
manufactured. Stairways in houses can have a
straight, continuous run without an intermediate
landing, or consist of two or more runs with
changes in direction, or may be curved, in which
case special design criteria apply. The minimum
allowable stairway headroom is 1.95 m (6 ft. 5 in.)
(see Figure 141).
The width of any landing must not be less
than the width of the stairs. Stairs in houses
and houses with a secondary suite must be at
least 860 mm (34 in.) wide measured between
wall faces.
The length of a landing in a house cannot be less
than 860 mm (3378 in.). The vertical height of
any flight of stairs cannot exceed 3.7 m (12 ft.).
Each step in a flight of stairs should have the
same height.
189
CHAPTER 17
Stairs
rise
width
total run
total
rise
Straight
long L
wide L
narrow U
wide U
190
CHAPTER 17
Stairs
Stringers
line of
leading edge
(nosing)
rise
run
90 mm (312 in.)
minimum effective depth
stringer
finish floor level
total run
191
CHAPTER 17
Stairs
nail or screw
nail or screw
tread return
moulding
balusters placed
in tread
cut stringer
192
CHAPTER 17
Stairs
Basement Stairs
Closed risers are safer but open risers may be
used for basement stairs (see Figure 143).
Exterior Stairs
Exterior stairs can be wood or concrete.
Concrete stairs with more than two risers
must be supported on piers or cantilevered
from the foundation wall. The dimensions
of risers and treads for exterior stairs are the
same as for interior stairs.
Ploughed stringer
stair tread leading edge
(nosing) slightly chamfered
ploughed stringer
Cut-out stringer
stair tread
(supported on cut-out)
cut-out stringer
Cut-out stringer with an
attached finish member
25 mm (1 in.) thick finished
member on outside of stringer
stair tread
(supported on cut-out)
cut-out stringer
193
CHAPTER 17
Stairs
Ramps
When a ramp is required for wheelchair access
(a barrier-free path of travel) to a house or a
house with a secondary suite, certain conditions
must be met so that it is safe and easy to use.
A level area must be provided at the top and the
bottom of the ramp and intermediate level areas
are required every 9 m (29 ft.)or where there is
a change in direction. The clear width must be
at least 870 mm (34 in.) and the slope must
not be greater than 1:12. Consult the local
building department for additional information.
194
CHAPTER 17
Stairs
RELATED PUBLICATIONS
About Your House: Accessible Housing by DesignRamps,
Canada Mortgage and Housing Corporation (product no. 65023)
About Your House: Preventing Falls on Stairs,
Canada Mortgage and Housing Corporation (product no. 63637)
195
CHAPTER 18
chimney extends
at least 600 mm
(2 ft.) above any
part of a roof
within 3 m (10 ft.)
roof
196
CHAPTER 18
Chimneys, Flues and Fireplaces
Masonry Chimneys
A masonry chimney consists of a liner and an
outer wall (Figure 145). Masonry chimneys
must be built on a concrete footing designed
to support the load. The size of the chimney
depends on the number, size and arrangement
of flues. The outer wall of a masonry chimney
must not be less than 75 mm (3 in.) and must
consist of solid masonry units. The NBC
provides minimum sizes for round and
rectangular flues for fireplace chimneys.
75 mm (3 in.) minimum
197
CHAPTER 18
Chimneys, Flues and Fireplaces
Factory-Built Flues
Factory-built flues do not require a foundation
(see Figure 147). The flue sections are comprised
of inner and outer stainless steel liners separated
by insulation. Provide clearance between the
outer wall of the flue and the framing and
provide lateral support with clips attached
to the framing. Use only factory-built flues
that have been tested and approved for use
in Canada.
FIREPLACES
Fireplaces can consist of solid masonry
construction, be factory-built, have steel
inserts for masonry or wood frame construction,
or be factory-built natural gas appliances.
Special wood pellet burning appliances are
available as well.
All fireplaces must be designed properly to provide
heat, safely remove combustion by-products and
not pose a fire hazard. Fireplaces should have
an external air supply so that warm, room air
is not used for combustion. A fireplace that is
a solid-fuel-burning appliance requires that
CO alarms be installed in living spaces,
especially near bedrooms.
Masonry Fireplaces
A conventional masonry fireplace has very
low heating efficiency because it draws large
amounts of room air up the flue that must be
replaced by air leakage through the building
envelope elsewhere in the house. This results
in a warm room where the fireplace is located
but a cold house elsewhere due to increased
air leakage. Masonry fireplaces located on an
exterior wall can be a significant source of
198
CHAPTER 18
Chimneys, Flues and Fireplaces
wall finish
mantelshelf
mantel
front hearth
flue lining
smoke chamber
smoke shelf
damper
throat
firebrick
ash dump
back hearth
ash pit
cleanout door
199
CHAPTER 18
Chimneys, Flues and Fireplaces
200
CHAPTER 18
Chimneys, Flues and Fireplaces
standoff
surround
nailing flange
201
CHAPTER 18
Chimneys, Flues and Fireplaces
Environmental Responsibility
Resource Efficiency
Energy Efficiency
Affordability
202
CHAPTER 19
203
CHAPTER 19
Plumbing, Electrical and Appliances
40 mm (1916 in.)
minimum
stud depth
minimum
23
204
CHAPTER 19
Plumbing, Electrical and Appliances
Roof Trusses
Roof trusses cannot be notched or drilled.
FRAMING FOR
PLUMBING SYSTEMS
The installation of the plumbing system
usually begins after the framing is complete.
The initial work is called roughing-in and
includes installing plumbing vents and drains
and all hot and cold water piping that will be
enclosed in the walls and ceilings and under
the basement floor. Since the bathtub must be
installed before the wall finish can be applied,
bathtub installation is usually included in
roughing-in.
bathtub
toilet
soil stack cleanout
washbasin or vanity
use 140 mm (6 in.)
stud wall when soil
stack continues
to upper floors
cleanout
floor drain in
front of laundry
tubs in basement
waste disposal piping
system buried under
concrete slab and
directed outside the
building to the
sanitary sewer
cleanout
exterior face of building
205
CHAPTER 19
Plumbing, Electrical and Appliances
end profile
of bathtub
overflow
washbasin
outlet
subflooring cut to
receive drain piping
drainage piping
from trap connected
to soil stack
drainage piping
from washbasin
bottom plate
and subflooring
cut for stack
toilet
toilet flange secured to subfloor
drainage piping
from bathtub
soil stack
206
CHAPTER 19
Plumbing, Electrical and Appliances
toilet
bathtub
soil stack and
vent pipe
cleanout at basement level
207
CHAPTER 19
Plumbing, Electrical and Appliances
208
CHAPTER 19
Plumbing, Electrical and Appliances
FRAMING DETAILS
FOR WIRING
The design and installation of the entire
wiring system is usually regulated by a provincial
electrical code, all of which are closely modelled
on the Canadian Electrical Code published by the
Canadian Standards Association. The provincial
conduit straps
conduit
conduit connector
meter socket
conduit adapter
conduit connector
service panel
entrance ell
209
CHAPTER 19
Plumbing, Electrical and Appliances
weather head
overhead wires
service mast
meter base and meter on exterior
3-wire 120-240V
service height above grade in accordance
with electrical code requirements
grounding wire
main breaker
distribution panel
12.7 mm (12 in.) support
panel fixed to wall
floor joists
water supply pipe
fixed to back-up strip
combination service
entrance panel
water meter
ground wire clamped
below shut-off valve
finished basement floor
Note: Service equipment must be grounded.
210
CHAPTER 19
Plumbing, Electrical and Appliances
double studs at
door opening
switch box to door framing
with two 100 mm (4 in.) nails
wires stapled as shown
to service panel
211
CHAPTER 19
Plumbing, Electrical and Appliances
Circuit breaker
212
CHAPTER 19
Plumbing, Electrical and Appliances
Smoke Alarms
The National Building Code and most
local building codes require early-warning,
fire- and smoke-detecting devices in dwellings.
Smoke alarms must be located in or near each
bedroom on each storey including basements
and mounted on or near the ceiling.
Energy Efficiency
213
CHAPTER 19
Plumbing, Electrical and Appliances
Continued
Environmental Responsibility
RELATED PUBLICATIONS
About Your House: Accessible Housing by DesignLiving Spaces,
Canada Mortgage and Housing Corporation (product no. 66095)
2010 National Plumbing Code of Canada,
National Research Council of Canada
Canadian Electrical Code,
Canadian Standards Association, product no. C22.1
214
CHAPTER 20
215
CHAPTER 20
Space Conditioning Systems
dining room
basement
up to toe-space in
kitchen counter
return air duct
basement
bedroom
bathroom
entrance hall
216
CHAPTER 20
Space Conditioning Systems
Furnaces
Furnaces heat houses by transferring the heat
produced from burning natural gas, propane
or oil, electric elements, or hydronic coils to air
that is distributed throughout the house and
circulated within each room by a supply and
return duct system. Furnaces are controlled
by thermostats installed in a central location.
Today, furnaces tend to be quite compact,
lightweight, and are easily installed in the
basement or crawl space, or in purpose-built
service rooms.
flue pipe
relay control box
heating unit
warm air supply
electrical conduit
fastened to
heating unit
Note: Maintain clearance between conbustible materials and heating appliances in accordance with
manufacturers instructions
217
CHAPTER 20
Space Conditioning Systems
218
CHAPTER 20
Space Conditioning Systems
219
CHAPTER 20
Space Conditioning Systems
Electric Baseboard
Heating Systems
Electric baseboard heating systems are common
in some provinces and territories. They are
installed at the wall-floor intersection in all
rooms, typically under windows. Most rooms
have thermostats located on interior walls
to control the baseboard. As baseboards are
connected to the electrical system by conventional
wiring, there are few implications for wood frame
construction. It may be necessary to ensure
there are an adequate number of studs in the
walls behind a baseboard to allow it to be firmly
connected to the wallotherwise additional
blocking may be required.
220
CHAPTER 20
Space Conditioning Systems
VENTILATION SYSTEMS
House ventilation is needed to maintain
acceptable indoor air quality (IAQ) and to
control indoor moisture levels. Air quality is
important for human health and well-being.
High interior moisture levels can promote
the growth of mold and mildew and adversely
affect human health and the durability of the
building envelope.
Ventilation can be provided naturally, typically
through operable windows, and mechanically
with fans and other equipment. Non-heating
season ventilation can be provided either naturally
or mechanically. Heating season ventilation
must be provided by a mechanical system.
Houses must be designed to make efficient
use of energy by using effective heating,
ventilating and air conditioning equipment
that is properly sized. Install mechanical
equipment inside the plane of insulation or
ensure the equipment is suited for installation
outdoors or in unheated space.
NATURAL VENTILATION
Natural ventilation through operable windows
can meet air change requirements during the
non-heating season when the air entering the
Canada Mortgage and Housing Corporation
221
CHAPTER 20
Space Conditioning Systems
MECHANICAL VENTILATION
It is well understood that the combination of
an airtight building envelope and an effective
and efficient mechanical ventilation system can
outperform a leaky house with no mechanical
ventilation system. A house that is built tight
and ventilated right will have lower heating
costs and greater year-round comfort. For this
reason, the NBC requires the installation of a
mechanical ventilation system in houses intended
for year-round occupancy. As a minimum,
the system must include a principal fan capable
of providing an air flow rate suitable for the
number of bedrooms; in most cases, supplemental
exhaust fans to ventilate high moisture generation
in areas such as kitchens and bathrooms;
and protection against depressurization that
222
CHAPTER 20
Space Conditioning Systems
223
CHAPTER 20
Space Conditioning Systems
exhaust fan
supply fan
condensate drain
exhaust fan
heat wheel
stale air from house
air supply
from outside
supply fan
224
CHAPTER 20
Space Conditioning Systems
225
CHAPTER 20
Space Conditioning Systems
Continued
Environmental Responsibility
Energy Efficiency
Affordability
RELATED PUBLICATIONS
2010 National Building Code of Canada,
National Research Council of Canada
CAN/CSA-F326-M91: Residential Mechanical Ventilation Systems,
Canadian Standards Association
CAN/CSA B149.1-10: Natural gas and propane installation,
Canadian Standards Association
226
CHAPTER 21
227
CHAPTER 21
Interior Wall and Ceiling Finishes
Nail Attachment
Gypsum board panels can be attached to
wood members by nails or screws (Figure 164).
Nails should be ringed, with 2.3 mm (332 in.)
shanks and 5.5 mm (732 in.) diameter heads.
The nails should be long enough to penetrate
at least 20 mm (34 in.) into wood supports.
Screws should be long enough to penetrate
at least 15 mm (58 in.) into wood supports.
The fastener heads are set slightly below the
surface without damaging the paper so that a
slight dimple is formed in the face of the board,
Horizontal application
and double nailing
double-nailing pattern
nail 50 mm (2 in.) apart
300 mm (12 in.) intervals
nail or screw to stud
recessed edge
stud
228
CHAPTER 21
Interior Wall and Ceiling Finishes
Screw Attachment
Special drywall screws are often used to fasten
gypsum board using screw guns. Screws are
usually spaced 300 mm (12 in.) on centre at both
the edge and intermediate supports. The distance
can be increased to 400 mm (16 in.) on walls
when the supports are not more than 400 mm
(16 in.) on centre. Where gypsum board provides
required bracing in braced wall panels in areas
exposed to high wind or earthquake forces,
the screw spacing must not be more than
300 mm (12 in.).
If two layers of gypsum board are needed,
such as for sound control or additional fire
rating, fasten the boards in the usual manner
with nails or screws. The fasteners for the
second layer must penetrate as much as for
the first layer.
sharp fold
Typical joint
stud
gypsum board
recessed edge
joint cement
tape
joint cement
feather edge
229
CHAPTER 21
Interior Wall and Ceiling Finishes
Finishing Joints
The taping and finishing of gypsum board should
be done at 10C (50F) or higher. Before the
joints are taped, remove all loose paper and
clean the joints. Fill all joints wider than 3 mm
(18 in.) with joint compound and let it dry.
Protect external corners with metal corner
beads, and tape inside corners using paper
tape folded as shown in Figure 165.
Joint compound is supplied premixed or in
powder form that is mixed with water to a soft
putty consistency. Apply the first layer of joint
compound in a band 125 mm (5 in.) wide along
the joint. Apply the tape and press it into the
wet compound with a trowel or wide-blade putty
knife. Remove excess compound, smooth the
tape and feather the compound band to zero
thickness at its outer edges.
After the first layer has dried, apply a second
layer in a band 200 mm (8 in.) wide on recessed
joints and 250 mm (10 in.) wide where the edges
of the board are not recessed. Feather the edges.
Apply a third layer and feather to a band 250 to
300 mm (10 to 12 in.) wide on recessed joints
and 400 mm (16 in.) on joints that are not
recessed. Make this layer as smooth as possible
to reduce sanding. When the third layer has set,
sand the feathered edges lightly with fine sand
paper and avoid damaging the paper surface of
the gypsum board.
Nail and screw heads and indentations in the
centre of the board are filled with two layers
of joint compound.
OTHER FINISHES
Other products such as plywood, OSB,
particleboard and lumber can be used for interior
finishes. Lumber, plywood and medium density
fibreboard (MDF) wainscoting are often used as
decorative finishes. In this application, they are
installed over and attached to the gypsum board
finish. Typical softwood species include cedar,
pine or hemlock; hardwoods include maple,
birch or cherry.
Canada Mortgage and Housing Corporation
230
CHAPTER 21
Interior Wall and Ceiling Finishes
Energy Efficiency
Resource Efficiency
Affordability
RELATED PUBLICATIONS
About Your House: Accessible Housing by DesignLiving Spaces,
Canada Mortgage and Housing Corporation (product no. 66095)
CAN/CGSB-19.22-M: Mildew-Resistant Sealing Compound for Tubs and Tiles,
Canadian General Standard Board
231
CHAPTER 22
Floor Coverings
SUB-FLOOR AND
UNDERLAY REQUIREMENTS
Sub-flooring is required under any finish
flooring that is not capable of supporting
specified live loads. The thickness of wood-strip
flooring required for various support conditions
232
CHAPTER 22
Floor Coverings
233
CHAPTER 22
Floor Coverings
LAMINATE AND
ENGINEERED FLOORING
Laminate flooring, an economical option,
is made of a melamine-infused paper laminated
to a particleboard substrate and comes with
Starter strip
shoe mould
base
wall finish
plate
6 mm (14 in.) expansion space
or as recommended by the
flooring manufacturer
when face-nailed and set,
shoe mould will cover nail
Nailing method
finish floor
fasteners angled at 45
234
CHAPTER 22
Floor Coverings
PARQUET FLOORING
Parquet flooring is made of small pieces of
wood arranged in a pattern and glued to a
backing to make tiles. Typical species used for
parquet flooring are birch, maple, beech and
oak. The tiles have mating edges. Flooring
manufacturers have developed a wide variety
of special patterns of flooring referred to as
parquet flooring with specific installation
directions. If parquet flooring is placed over
lumber subflooring or panel subflooring
whose edges are not supported (blocked
or tongue-and-groove), panel underlay
is required.
RESILIENT FLOORING
Resilient flooring is water-resistant and is
used in bathrooms, kitchens, laundry rooms,
entrance halls and general storage areas.
The more common types of resilient floor
covering are vinyl and rubber. Both types
are available in tile and sheet form. If resilient
flooring is placed over lumber subflooring or
panel subflooring whose edges are not supported
(blocked or tongue-and-groove), panel underlay
is required.
Resilient flooring is usually cemented to the
underlay with an adhesive recommended by
the manufacturer for its compatibility with
CARPET
Carpet is commonly used in living rooms,
bedrooms and family rooms. It should not
be used in areas where water damage or staining
is likely to occur. When carpet is desired in
such areas, a synthetic-fibre type should be
used. For hygienic reasons, carpet is not
recommended for use in rooms containing
a toilet.
Except for cushion-backed carpeting, felt or
polymeric carpet underlay should be used.
When a subfloor is not constructed as a
combination subfloor and underlay as described
in Chapter 9, an underlay must be installed.
CERAMIC, PORCELAIN,
GRANITE AND MARBLE TILE
Ceramic, porcelain, granite and marble tile
is water-resistant and is typically used in
bathrooms, kitchens, entrances and for
fireplace hearths. It is available in different
colours either with glazed or unglazed surfaces.
Tile may be laid either directly on a concrete,
plywood or OSB base with an adhesive or in a
mortar bed about 30 mm (1316 in.) thick over
235
CHAPTER 22
Floor Coverings
ceramic tile
plywood underlay
adhesive
subfloor
floor joists
236
CHAPTER 22
Floor Coverings
Environmental Responsibility
Affordability
237
CHAPTER 23
INTERIOR DOORS
Interior doors are used to separate living areas
and provide privacy. Options include single
and double swinging doors, and pocket doors.
Sliding doors and folding doors are popular
choices for clothes closets.
Bedroom and passageway doors must be at least
760 mm (30 in.) wide and 1.98 m (6 ft. 8 in.)
high. Doors providing access to laundry and
utility rooms must be at least 810 mm (32 in.)
238
CHAPTER 23
Interior Doors, Frames and Trim
Door Installation
Interior doors are most often purchased as
pre-hung, meaning that that the door,
hardware and frame are provided and holes
and notches for the hardware are ready for
installation into the framing rough opening.
Door frames are made up of two jambs and a
head, together with separate mouldings called
doorstops. Stock jambs are made of 19 mm
(34 in. nominal) lumber, cut to widths to suit
168 Interior door frame showing typical connection between jamb and head
head
dado
jamb
stop
169 Door frame and trim showing frame blind-nailed under doorstop
framing studs
wall finish
shingle wedge
nails (under doorstop)
jamb
doorstop
door thickness
casing
5-6 mm (316 - 14 in.)
239
CHAPTER 23
Interior Doors, Frames and Trim
1 mm (132 in.)
900 mm (36 in.)
hinge
275 mm (11 in.)
19 mm (34 in.)
240
CHAPTER 23
Interior Doors, Frames and Trim
HARDWARE INSTALLATION
Hinges must be the proper size for the weight
of door they support. For 35 mm (1 38 in.)
thick interior doors, use two 76 76 mm
(3 3 in.) butt hinges. For heavier doors,
use three hinges. Fit the door into the jamb
opening to ensure it has the proper clearances,
then remove it and install the hinges.
If not factory prepared, mortise the door to
nest the half hinges. The edge of each hinge
should be at least 3 mm (18 in.) back from the
face of the door. When the hinge halves are
screwed in place, they must be flush with the
surface and square.
Strike plate
stop
wall finish
casing
strike plate
Door stops
casing
jamb
stop
slight bevel
door
hinge
1 mm (132 in.)
241
CHAPTER 23
Interior Doors, Frames and Trim
242
CHAPTER 23
Interior Doors, Frames and Trim
MILLWORK
Kitchen Cabinets
bar counter
toe space
island base cabinet
243
CHAPTER 23
Interior Doors, Frames and Trim
Closets
Clothes closets are commonly provided
with shelves and a closet rod or metal
track. Manufactured storage units may
be used in lieu of a site-built closet or may
be installed in closets to maximize storage
room. Built-in cabinets may also be used
in bedrooms. Larger houses may have
small rooms (walk-in closets) for clothes
storage. Closets on exterior walls should
be avoidedthe lack of air circulation and
presence of clothing and other items act
as unintentional insulation, lowering the
interior wall temperature and increasing
the risk of condensation.
A standard interior door (Figure 174),
sliding doors, multiple doors or bi-fold
doors can be used in pairs or other multiple
combinations to provide optimum access
to closet space.
Built-in dresser
drawers
Clothes closet
shelf
closet rod
finger pull
sliding doors
rack
244
CHAPTER 23
Interior Doors, Frames and Trim
Affordability
Environmental Responsibility
245
CHAPTER 24
Coating Finishes
COMPOSITION OF COATINGS
Paint, varnish, stain and lacquer have three
major components:
Solvent: The solvent in a coating product
thins the pigment/resin mixture to make it
flowable (easy to apply). During the drying
process, the solvent evaporates and has no
246
CHAPTER 24
Coating Finishes
TYPES OF COATINGS
Paint
Paint is a coating that provides solid colour.
The vast majority of residential-quality paints
use alkyd or latex as their principal resin
ingredients. Properties such as gloss, sheen,
hardness durability (including ability to be
scrubbed without burnishing) and hiding
ability are attained by adjusting the
pigment/resin ratio.
The suitability of paint for exterior or interior
application is determined by the chemical
composition of the resin. Resin for exterior
paint provides the elasticity to accommodate
temperature and dimensional changes, and
permeability to allow moisture movement
without blistering the paint.
Stain
Stain is a coating with a high solvent content
that causes colouring to be absorbed into the cell
openings of wood surfaces. The degree to which
a stain penetrates can be adjusted for specific
applications. Although some stains penetrate
to the extent that they leave no surface residue,
most penetrate but leave some surface coating.
Stains are specially formulated to meet the
specific requirements of interior and exterior
uses. For exterior applications, stain is usually
used alone but, in some instances, it may
be top-coated with exterior quality varnish.
When used alone, stain will alter the colour
of the wood and provide a degree of protection
from sun and water.
For interior applications, stain is used to alter
the colour of wood and to accent grain and
texture. A transparent topcoat is usually applied
to seal the surface.
Lacquer
Lacquer is a fast-drying, protective top-coating
used for fine finishing of architectural woodwork
and furniture. It is normally used as a transparent
finish, like varnish, to display the wood grain,
but is also available in solid colours.
Canada Mortgage and Housing Corporation
247
CHAPTER 24
Coating Finishes
APPLICATION
Proper surface preparation is essential to a
successful coating finish. The application
temperature is critical. Apply at temperatures
above 10 C (50F) to surfaces that are dry,
clean and dust free.
If latex paint is applied at a low temperature,
proper film formation will not occur, making it
susceptible to peeling. At low temperatures,
alkyd paint dries too slowly and is susceptible
to damage.
Canada Mortgage and Housing Corporation
248
CHAPTER 24
Coating Finishes
Exterior Coatings
The durability of exterior coatings depends
on whether the coating permits the movement
of moisture, thereby avoiding blistering, and
excludes the ultraviolet portion of sunlight,
which causes the coating to deteriorate.
Wood products treated with water-borne
wood preservatives can be coated using the
same products and techniques as for untreated
materials. As is the case with all wood products
used in exterior applications, coating performance
will be best if the moisture content of the
underlying material is 19 per cent or less.
Primer provides some early protection and
ensures adhesion between wood and topcoats.
Prime surfaces for painting as quickly as possible
after installation. As wood weathers, it takes
on a grey appearance that can seriously affect
adhesion of paint. Sand it off before priming.
Use alkyd paints for doors and trim where
durability is needed, and latex paints for wood
cladding to allow moisture movement and
minimize the potential for blistering.
Varnish made for exterior use contains no
colour pigment and has only limited ability
to screen ultraviolet light. This means varnish
Interior Coatings
Interior surfaces are painted to provide a
pleasing appearance and to protect them
from damage by moisture that is prevalent
in the kitchen, bathroom and laundry rooms.
Painted surfaces are also easier to clean.
Wall and ceiling gypsum board finishes are
painted. Doors, trim, and interior millwork
may be painted, stained or varnished.
To prevent running or sagging, varnish should
not be applied in thick coats. Two thin coats,
with light sanding and sufficient drying time
between, are adequate for most residential
applications. Items such as stair treads and
handrails may warrant a third coat.
When performing interior painting, provide
sufficient ventilation and lighting. Solvent-based
paints and cleaners should be stored outside the
living space. Dispose of all rags, paints, stains and
thinners in an appropriate manner, usually at
special depots for toxic wastes.
In all cases, follow the manufacturers application
instructions to attain proper finish appearance
and performance.
Affordability
249
CHAPTER 25
250
CHAPTER 25
Eavestroughs and Downspouts
Environmental Responsibility
251
CHAPTER 26
252
CHAPTER 26
Decks, Porches and Balconies
100 mm (4 in.)
maximum opening
Guard height
guard not required
900 mm (36 in.)
1 070 mm (42 in.)
guard
height
height
of deck
beam
post bolted to joists
post bolted through block
between joists to rim joist
angle bracket
140 x 140 mm (6 x 6 in.) post
200 mm (8 in.)
above grade
depth of
foundation
post saddle
concrete pier supported by
rock, drained granular material
or below the frost line for
decks > 600 mm (2 ft.) above
ground or with more than 3 risers
253
CHAPTER 26
Decks, Porches and Balconies
254
CHAPTER 26
Decks, Porches and Balconies
Affordability
255
CHAPTER 27
GARAGES
Garages can be attached or detached. Built-in
garages with living accommodation over the
garage area are common in two-storey houses.
In an attached garage, a complete air barrier
is required in walls and ceiling separating the
garage from occupied spaces. Doors separating
a garage from the house are required to be
weatherstripped and be self-closing to keep
garage exhaust and vapours from contaminating
living areas. The operation of motor vehicles in
garages is a potential source of carbon monoxide
(CO), a colourless, odourless gas that can
accumulate in lethal concentrations in enclosed
spaces without occupants being aware of it. If a
garage is heated, the heating system should be
separate from the house heating system to reduce
the risk of garage fumes entering the house.
256
CHAPTER 27
Garages and Carports
living space
garage
living
space
garage door
sloped driveway
257
CHAPTER 27
Garages and Carports
CARPORTS
Carport roofs are usually supported by posts
located on top of concrete piers. Piers should be at
least 190 190 mm (8 8 in.). Cylindrical piers
are often used for this purpose. The base of the
pier should be sufficiently large to ensure that
the safe bearing pressure for the soil is not
exceeded and far enough below grade to prevent
frost heaving.
Where wood posts are used, the concrete piers
should extend at least 150 mm (6 in.) above
the ground to protect the posts from ground
moisture. Anchor posts securely to both piers
and roof framing to resist wind uplift.
258
CHAPTER 28
SURFACE DRAINAGE
DRIVEWAYS
A driveway should be at least 2.4 m (8 ft.) wide
and 3 m (10 ft.) wide when it also serves as a
walkway. It should have a slope suitable for
traction in winter conditions, provide good
visibility at the street intersection and be
259
CHAPTER 28
Surface Drainage, Driveways and Walkways
WALKWAYS
Cast-in-place concrete, interlocking pavers and
flagstones are commonly used for walkways.
They should be built on a well-compacted
base with a slight slope to drain surface water.
The recommended maximum gradient for a
walkway along its length is 5 per cent with a
maximum cross-slope of 2 per cent. Concrete
walks should be at least 100 mm (4 in.) thick.
Locate control joints spaced about 1.5 times
the walkway width.
Interlocking pavers and flagstones should be
placed over a compacted levelling bed of sand
or stone dust.
Environmental Responsibility
RELATED PUBLICATIONS
Landscape Guide for Canadian Homes,
Canada Mortgage and Housing Corporation (publication no. 63523)
260
CHAPTER 29
Maintenance
RELATED PUBLICATIONS
Maintenance Matters (bulletins),
Homeowner Protection Office, Branch of BC Housing
261
APPENDIX A
Tables
262
APPENDIX A
Tables
Table 1
Conversion factors
Framing terms
Metric - dimension
Imperial - nominal
(unplaned) dimensions
38 x 38 mm
2 x 2 in.
38 x 89 mm
2 x 4 in.
38 x 140 mm
2 x 6 in.
38 x 184 mm
2 x 8 in.
38 x 235 mm
2 x 10 in.
38 x 286 mm
2 x 12 in.
600 x 2,400 mm
2 x 8 ft.
1,200 x 2,400 mm
4 x 8 ft.
300 mm
12 in. O.C.
400 mm
16 in. O.C.
600 mm
24 in. O.C.
x 1.8 + 32 =
kg
x 2.205 =
lb
kPa
x 0.1450 =
lbf/in2 (psi)
kPa
x 20.88 =
lbf/ft2
x 0.2200 =
gal (imp.)
L/s
x 13.20 =
gal/min (gmp)
lx
x 0.09290 =
ft-candle
x 3.281 =
ft
m2
x 10.76 =
ft2
m3
x 35.31 =
ft3
mm
x 0.03937 =
in.
m3/h
x 0.5886
ft3/min (cfm)
m/s
x 196.8 =
ft/min
MJ
x 947.8 =
Btu
x 0.2248
lbf
Watts
x 3.412 =
Btu/h
ng/(Pa.s.m2)
x 0.0174
Perms
Pa
x 0.004014 =
in. of water
Lumber
Panels
Spacings
Units of Measure
263
APPENDIX A
Tables
Table 2
Concrete mixes (by volume)
Concrete Strength
Cement (part)
Sand (parts)
Coarse Aggregate
2,200 psi
(15 MPa)
4 parts up to
50 mm (2 in.) in size
6 parts pit
run gravel
134
3 parts up to
40 mm (112 in.)
in size
3,000 psi
(20 MPa)
Note to Table 2
1. For higher strength concretes, use commercial suppliers to ensure strength and air entrainement requirements are met
Table 3
Minimum depths of foundations
Foundations containing heated
basement or crawl space
Foundations containing
no heated space
Poor soil
drainage
Poor soil
drainage
Clay or soils
not clearly
defined
1.2 m (4 ft.)
1.2 m (4 ft.)
Silt
No limit
No limit
Coarse
grained soils
No limit
No limit
No limit
Rock
No limit
No limit
No limit
No limit
Type of Soil
264
APPENDIX A
Tables
Table 4
Minimum footing sizes (Length of supported joists 4.9 m [16 ft.] or less)
(Design floor load 2.4 kN/m2 [50 lb./ft.2] maximum)
Minimum Widths of Strip Footings, mm (in.)
No. of Floors
Supported
Supporting
Exterior Walls
Supporting
Interior Walls
Minimum Area of
Column Footings1,
m2 (sq. ft.)
250 (10)2
200 (8)3
0.4 (4.3)
350 (14)2
350 (14)3
0.75 (8)
450 (18)2
500 (20)3
1.0 (11)
Notes to Table 4
1. Sizes are based on columns spaced 3 m (9 ft., 10 in.) (on centre). For other column spacings, footing areas must be adjusted
in proportion to the distance between columns.
2. For each storey of masonry veneer over wood-frame construction, footing widths must be increased by 65 mm (212 in.).
For each storey of masonry construction other than foundation walls, the footing width must be increased by 130 mm (518 in.).
3. For each storey of masonry supported by the footing, the footing width must be increased by 100 mm (4 in.).
Table 5
Minimum thickness of foundation walls
Maximum Height of Exterior Finish Grade Above
Basement Floor or Inside Grade, m (ft.in.)
Type of
Foundation Wall
Minimum Wall
Thickness, mm (in.)
Solid concrete,
15 MPa (2,200 psi)
minimum strength
150 (6)
0.80 (27)
1.50 (411)
200 (8)
1.20 (311)
2.15 (70)
250 (10)
1.40 (47)
2.30 (76)
300 (12)
1.50 (411)
2.30 (76)
150 (6)
0.80 (27)
1.80 (510)
200 (8)
1.20 (311)
2.30 (76)
250 (10)
1.40 (47)
2.30 (76)
300 (12)
1.50 (411)
2.30 (76)
140 (512)
0.60 (111)
0.80 (27)
240 (9716)
1.20 (311)
1.80 (510)
290 (11716)
1.40 (47)
2.20 (72)
Solid concrete,
20 MPa (2,900 psi)
minimum strength
Unit masonry
Notes to Table 5
1. Foundation walls are considered laterally supported at the top if the floor joists are embedded in the top of the foundation
walls, or if the floor system is anchored to the top of the foundation walls with anchor bolts, in which case the joists may
run either parallel or perpendicular to the foundation wall.
2. When a foundation wall contains an opening of more than 1.2 m (3 ft.11 in.) in length or openings in more than 25 per cent
of its length, the portion of the wall beneath such openings is considered laterally unsupported unless the wall around the
opening is reinforced to withstand the earth pressure.
3. When the length of solid wall between windows is less than the average length of the windows, the combined length of
such windows is considered a single opening.
4. When foundation walls support solid masonry walls, the foundation wall is considered laterally supported by the first floor.
265
APPENDIX A
Tables
Table 6
Mortar mix proportions (by volume)
Permissible
Use of Mortar
Portland
Cement
Masonry
Cement
(Type H)
All locations1
2 to 1
All locations1,
except foundation
walls and piers
All locations,
except loadbearing
walls of hollow units
114 to 212
All non-loadbearing
partitions and all
loadbearing walls
of solid units except
foundation walls
214 to 4
Lime
Aggregate
4 to 12
2 to 114
Note to Table 6
1. Must not be used for sand-lime brick or concrete brick.
266
APPENDIX A
Tables
Table 7
Dimension lumber grades and uses
Common
Grade Mix1
Sizes, mm (in.)
Grades
38 to 89 mm
(2 to 4 in.) thick;
38 to 89 mm
(2 to 4 in.) wide
Select
structural
No. 1 and
No. 2
No. 2
and better
(No. 2 & Btr.)
No. 33
Construction3
Standard3
Standard
and better
(Std. & Btr.)
Utility2
Economy2
Select
Structural
No. 1 and
No. 2
No. 33
Economy2
Stud3
Economy
stud2
38 to 89 mm
(2 to 4 in.) thick;
114 mm (5 in. )
and wider
38 to 89 mm
(2 to 4 in.) thick;
38 mm (2 in.)
and wider
Principal Uses
Grade
Category
Structural
light
framing
Light
framing
Structural
joists and
planks
Stud
Notes to Table 7
1. For ease in grade sorting at the mill, the higher grades are combined and sold as a grade mix. Pieces of lumber in the grade
mix are still individually grade stamped.
2. Except for the utility and economy grades, all grades are stress graded, which means specified strengths have been assigned
and span tables calculated.
3. Construction, Standard, Stud and No. 3 Grades are typically used in designs that are not composed of 3 or more essentially
parallel members spaced on 600 mm (24 in.) centres or less, so arranged or connected to mutually support loading.
267
APPENDIX A
Tables
Table 8
Sizes for dimension lumber and boards
Boards
Dimension
Lumber
Metric Equivalents, mm
Dry
Green
Metric
Nomenclature,
mm
38 x 38
40 x 40
38 x 38
2x2
112 x 112
1916 x 1916
64
65
64
212
2916
89
90
89
312
3916
140
143
140
512
558
184
190
184
714
712
235
241
235
10
914
912
286
292
286
12
1114
1112
64 x 64
65 x 65
64 x 64
3 x 3, etc.
212 x 212
2916 x 2916
89 x 89
90 x 90
89 x 89
4 x 4, etc.
312 x 312
3916 x 3916
19 x 38
21 x 40
19 x 38
1x2
13
64
65
64
212
2916
89
90
89
312
3916
114
117
114
412
458
140
143
140
512
558
184
190
184
714
712
235
241
235
10
914
912
286
292
286
12
1114
1112
25 x 38
26 x 40
25 x 38
114 x 2, etc.
1 x 112
1132 x 1916
32 x 38
33 x 40
32 x 38
112 x 2, etc.
114 x 112
1932 x 1916
Nominal
Sizes, in.
Dry
Green
4 x 112
16 x 1916
268
APPENDIX A
Tables
Table 9
Facsimiles of lumber grade marks approved for use in Canada
Alberta Forest Products Association
900, 10707 100 Avenue
Edmonton, Alberta T5J 3M1
Tel: 780-452-2841
Email: info@albertaforestproducts.ca
Website: www.albertaforestproducts.ca
269
APPENDIX A
Tables
Table 9 (continued)
Facsimiles of lumber grade marks approved for use in Canada
Maritime Lumber Bureau
P.O. Box 459
Amherst, Nova Scotia B4H 4A1
Tel: 902-667-3889
Website: www.mlb.ca
Newfoundland and Labrador
Lumber Producers Association
P.O. Box 8
Glovertown
Newfoundland and Labrador A0G 2L0
Email: nllpa@personainternet.com
Tel: 709-533-2206
Ontario Forest Industries Association
(Home of CLA Grading and Inspection)
8 King Street East, Suite 1704
Toronto, Ontario M5C 1C3
Tel: 416-368-6188
Email: info@ofia.com
Website: www.ofia.com
Ontario Lumber Manufacturers Agency
244 Viau Road
Noelville, Ontario P0M 2N0
Tel: 705-618-3403
Email: info@olma.ca
Website: www.olma.ca
Pacific Lumber Inspection Bureau
P.O. Box 19118
4th Avenue Postal Outlet
Vancouver, British Columbia V6K 4R8
Tel: 604-732-1782
Email: info@plib.org
Website: www.plib.org
Qubec Forest Industry Council
1175, avenue Lavigerie, bureau 200
Qubec City, Quebec G1V 4P1
Tel: 418-657-7916
Email: info@QFIC.g.ca
Website: www.qfic.qc.ca
270
APPENDIX A
Tables
Table 10
Commercial species of lumber
Commercial Species
Group Designation
Grade Stamp
Identification
Species in
Combination
Spruce
Pine Fir
SPF
Douglas Fir
Larch
D. Fir L
Douglas fir,
Western larch
Hem Fir
Hem Fir
Pacific coast
hemlock,
amabilis fir
Northern
Species
North
Western
red cedar
North
Red pine,
ponderosa pine
Western white
pine, eastern
white pine
Trembling aspen,
largetooth aspen,
balsam poplar
Wood Characteristics
271
APPENDIX A
Tables
Table 11
Effective thermal resistance of assemblies in buildings with a
heat-recovery ventilator
Heating degree-days of building location,1 in celsius degree-days
Zone 4
Zone 5
Zone 6
Zone 7A
Zone 7B
Zone 8
<3000
3000 - 3999
4000 - 4999
5000 - 5999
6000 - 6999
>7000
Vancouver,
Kamloops,
Prince
Calgary, AB
Cold Lake,
NWT and
BC
BC
Rupert, BC
Regina, SK
AB
Nunavut
Kelowna, BC Lethbridge,
Winnipeg,
Whitehorse,
Toronto, ON BC
MB
YK
Ottawa, ON
Quebec City,
Montreal,
QC
QC
Edmundston,
Halifax, NS
NB
Minimum Effective Thermal Resistance
RSI m2K/W (R ft2Fh/Btu)
Building assembly above ground
Ceilings
10.43
6.91 (39.2)
6.91 (39.2)
8.67 (49.2)
8.67 (49.2)
10.43 (59.22)
below attics
(59.22)
Cathedral
ceilings and
4.67 (26.5)
4.67 (26.5)
4.67 (26.5)
5.02 (28.5)
5.02 (28.5)
5.02 (28.5)
flat roofs
Walls2
2.78 (15.8)
2.97 (16.9)
2.97 (16.9)
2.97 (16.9)
3.08 (17.5)
3.08 (17.5)
Floors over
unheated
4.67 (26.5)
4.67 (26.5)
4.67 (26.5)
5.02 (28.5)
5.02 (28.5)
5.02 (28.5)
spaces
Building assembly below grade or in contact with the ground1
Foundation
1.99 (11.3)
2.98 (16.9)
2.98 (16.9)
2.98 (16.9)
2.98 (16.9)
2.98 (16.9)
walls
Unheated
floors3
below frost
Uninsulated Uninsulated
Uninsulated
Uninsulated
Uninsulated
Uninsulated
4, 5
line
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
above frost
line5
Heated and
unheated floors n/a
n/a
n/a
n/a
4.44 (25.2)
4.44 (25.2)
on permafrost
Heated floors6 2.32 (13.2)
2.32 (13.2)
2.32 (13.2)
2.84 (16.1)
2.84 (16.1)
2.84 (16.1)
Slabs-on-grade
with an integral 1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
2.84 (16.1)
2.84 (16.1)
3.72 (21.1)
6
footing
Climate Zone
Heating-degree
days
Typical
Locations
Notes to Table 11
1. See NBC 1.1.3.1.
2. See NBC 9.36.2.8.(3) for requirements concerning the above-ground portion of foundation walls.
3. Does not apply to below-grade floors over heated crawl spaces.
4. Typically applies to floors-on-ground in full-height basements.
5. Refers to undisturbed frost line before house is constructed.
6. See NBC 9.25.2.3.(5) for requirement on placement of insulation. The design of slabs-on-grade with an integral footing
is addressed in NBC Part 4 (see Article 9.16.1.2.).
272
APPENDIX A
Tables
Table 12
Effective thermal resistance of assemblies in buildings without a heat
recovery ventilator
Heating degree-days of building location,1 in celsius degree-days
Zone 4
Zone 5
Zone 6
Zone 7A
Zone 7B
Zone 8
<3000
3000 - 3999
4000 - 4999
5000 - 5999
6000 - 6999
>7000
Vancouver,
Kamloops,
Prince
Calgary, AB
Cold Lake,
NWT and
BC
BC
Rupert, BC
Regina, SK
AB
Nunavut
Kelowna, BC Lethbridge,
Winnipeg,
Whitehorse,
Toronto, ON BC
MB
YK
Ottawa, ON
Quebec City,
Montreal,
QC
QC
Edmundston,
Halifax, NS
NB
Minimum Effective Thermal Resistance
RSI m2K/W (R ft2Fh/Btu)
Building assembly above ground
Ceilings
6.91 (39.2)
8.67 (49.2)
8.67 (49.2)
10.43 (59.2)
10.43 (59.2)
10.43 (59.2)
below attics
Cathedral
ceilings and
4.67 (26.5)
4.67 (26.5)
4.67 (26.5)
5.02 (28.5)
5.02 (28.5)
5.02 (28.5)
flat roofs
Walls2
2.78 (15.8)
3.08 (17.5)
3.08 (17.5)
3.08 (17.5)
3.85 (21.9)
3.85 (21.9)
Floors over
unheated
4.67 (26.5)
4.67 (26.5)
4.67 (26.5)
5.02 (28.5)
5.02 (28.5)
5.02 (28.5)
spaces
Building assembly below grade or in contact with the ground1
Foundation
1.99 (11.3)
2.98 (16.9)
2.98 (16.9)
3.46 (19.6)
3.46 (19.6)
3.97 (22.5)
walls
Unheated
floors3
below frost
Uninsulated Uninsulated
Uninsulated
Uninsulated
Uninsulated
Uninsulated
4, 5
line
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
above frost
line5
Heated and
unheated floors n/a
n/a
n/a
n/a
4.44 (25.2)
4.44 (25.2)
on permafrost
Heated floors6 2.32 (13.2)
2.32 (13.2)
2.32 (13.2)
2.84 (16.1)
2.84 (16.1)
2.84 (16.1)
Slabs-on-grade
with an integral 1.96 (11.1)
1.96 (11.1)
1.96 (11.1)
3.72 (21.1)
3.72 (21.1)
4.59 (26.1)
6
footing
Climate Zone
Heating-degree
days
Typical
Locations
Notes to Table 12
1. See NBC 1.1.3.1.
2. See NBC 9.36.2.8.(3) for requirements concerning the above-ground portion of foundation walls.
3. Does not apply to below-grade floors over heated crawl spaces.
4. Typically applies to floors-on-ground in full-height basements.
5. Refers to undisturbed frost line before house is constructed.
6. See NBC 9.25.2.3.(5) for requirement on placement of insulation. The design of slabs-on-grade with an integral footing is
addressed in NBC Part 4 (see Article 9.16.1.2.).
273
APPENDIX A
Tables
Table 13
Required thermal characteristics of windows, doors and skylights
Zone 4
<3000
Zone 5
3000 - 3999
Zone 6
4000 - 4999
Zone 7A
5000 - 5999
Zone 7B
6000 - 6999
Zone 8
>7000
Typical
Locations
Vancouver,
BC
Kamloops,
BC
Kelowna, BC
Toronto, ON
Prince
Rupert, BC
Lethbridge,
BC
Ottawa, ON
Montreal,
QC
Halifax, NS
Calgary, AB
Regina, SK
Winnipeg,
MB
Quebec City,
QC
Edmundston,
NB
Cold Lake,
AB
Whitehorse,
YK
NWT and
Nunavut
Thermal Characteristics
Climate Zone
Heating-degree
days
1.60
1.40
1.40
25
25
29
29
2.40
2.40
Windows
and
Doors2
1.80
Skylights
1.80
21
2.90
2.70
2.70
Notes to Table 13
1. See NBC 1.1.3.1.
2. Except skylights and glass block assemblies
274
APPENDIX A
Tables
Table 14
Comparison of typical window thermal efficiencies
Thermal performance of a typical casement window with low conductivity edge seal
Aluminum frame
with thermal break
Fibreglass frame
RSI
ER
RSI
ER
RSI
ER
Double glazed
clear with air fill
0.28
1.59
0.62
0.6
0.36
2.04
0.49
15.1
0.42
2.38
0.42
21.0
Double glazed
low-E with air fill
0.35
1.99
0.50
7.3
0.47
2.67
0.37
22.9
0.55
3.12
0.32
28.5
Double glazed
low-E with argon
0.37
2.10
0.48
11.0
0.51
2.90
0.34
26.7
0.61
3.46
0.29
32.0
Triple glazed
clear with air fill
0.35
1.99
0.50
7.3
0.50
2.84
0.35
28.2
0.56
3.18
0.31
29.2
Triple glazed
low-E with air fill
0.39
2.21
0.45
12.1
0.60
3.41
0.29
30.5
0.68
3.86
0.26
33.8
Triple glazed
low-E with argon
0.41
2.33
0.43
14.8
0.65
3.69
0.27
33.2
0.75
4.25
0.24
34.6
275
APPENDIX A
Tables
Table 15
Maximum spans for built-up floor beams supporting not more than one floor1, 2
Commercial
Designation
Douglas
Fir Larch
Grade
No. 1
and
No. 2
Hem Fir
No. 1
and
No. 2
Spruce
Pine Fir
No. 1
and
No. 2
Supported
Length,5, 6
m
ft.
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
3.42
112
3.06
100
2.80
91
2.59
85
2.42
711
2.28
75
2.17
71
3.55
117
3.21
105
2.93
97
2.72
810
2.54
83
2.39
710
2.27
75
3.38
110
3.14
103
2.95
98
2.80
92
2.63
87
2.48
81
2.35
78
3.82
126
3.42
112
3.13
102
2.89
95
2.71
810
2.55
84
2.42
711
3.82
126
3.55
117
3.28
108
3.04
911
2.84
93
2.68
89
2.54
83
3.64
1111
3.38
110
3.18
105
3.02
910
2.89
95
2.77
90
2.63
87
3.63
1110
3.24
107
2.96
98
2.74
811
2.56
84
2.42
710
2.29
76
3.80
125
3.40
111
3.11
101
2.88
94
2.69
89
2.54
83
2.41
710
3.92
1210
3.52
116
3.22
106
2.98
98
2.79
91
2.63
87
2.49
81
4.19
138
3.75
122
3.42
112
3.17
104
2.96
98
2.79
91
2.65
87
4.39
144
3.93
129
3.59
118
3.32
1010
3.11
101
2.93
96
2.78
90
4.32
141
4.01
131
3.71
121
3.44
112
3.22
106
3.03
910
2.88
94
4.68
153
4.19
138
3.82
125
3.54
116
3.31
109
3.12
102
2.96
98
4.88
1511
4.39
144
4.01
131
3.71
121
3.47
114
3.27
108
3.11
101
4.65
152
4.32
141
4.06
133
3.84
126
3.60
118
3.39
110
3.22
106
4.21
138
3.76
123
3.44
112
3.18
104
2.98
98
2.81
92
2.66
88
4.41
144
3.95
1210
3.60
119
3.34
1010
3.12
102
2.94
97
2.79
91
4.57
1411
4.09
134
3.73
122
3.46
113
3.23
106
3.05
911
2.89
95
4.86
1510
4.35
142
3.97
1211
3.67
1111
3.44
112
3.24
107
3.07
100
5.10
1607
4.56
1410
4.16
137
3.85
126
3.60
119
3.40
111
3.22
106
5.25
172
4.72
154
4.31
140
3.99
130
3.73
122
3.52
115
3.34
1010
5.43
178
4.86
1510
4.44
145
4.11
134
3.84
126
3.62
119
3.44
112
5.70
187
5.10
167
4.65
152
4.31
140
4.03
131
3.80
124
3.60
119
5.59
183
5.25
172
4.82
158
4.46
146
4.17
137
3.93
1210
3.73
122
Continued on p. 277
276
APPENDIX A
Tables
Table 15 (continued)
Maximum spans for built-up floor beams supporting not more than one floor1, 2
Commercial
Designation
Northern
Species
Grade
No. 1
and
No. 2
Supported
Length,5, 6
m
ft.
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.99
99
2.67
88
2.44
711
2.26
74
2.11
610
1.99
66
1.89
62
3.29
109
2.99
99
2.73
810
2.52
83
2.36
78
2.23
73
2.11
610
3.16
103
2.83
92
2.58
85
2.39
79
2.24
73
2.11
610
2.00
66
3.65
1111
3.27
108
2.98
98
2.76
90
2.58
85
2.43
711
2.31
76
4.08
133
3.65
1111
3.33
1010
3.09
101
2.89
95
2.72
810
2.58
85
3.67
1111
3.28
108
3.00
99
2.77
90
2.59
85
2.45
80
2.32
77
4.24
139
3.79
124
3.46
113
3.20
105
3.00
99
2.82
92
2.68
89
4.74
155
4.24
139
3.87
127
3.58
118
3.35
1011
3.16
103
3.00
99
Notes to Table 15
1. Spans apply only where the floors serve residential areas.
2. When the floors have a concrete topping of not more than 51 mm (2 in.), the spans must be multiplied by 0.8.
3. Spans are clear spans between supports. For total span, add two bearing lengths.
4. 3-ply beams with supported lengths greater than 4.2 m (13 ft.8 in.) require 114 mm (412 in.) of bearing. All other beams
require 76 mm (3 in.) bearing.
5. Supported length means half the sum of the joist spans on both sides of the beam.
6. Straight interpolation may be used for other supported lengths.
277
APPENDIX A
Tables
Table 16
Maximum spans for built-up floor beams supporting not more than two floors1, 2
Commercial
Designation
Douglas
Fir Larch
Grade
No. 1
and
No. 2
Hem Fir
No. 1
and
No. 2
Spruce
Pine Fir
No. 1
and
No. 2
Supported
Length,
m5, 6
ft
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.56
84
2.29
76
2.09
610
1.94
64
1.81
511
1.71
57
1.62
53
2.69
89
2.41
710
2.20
72
2.03
67
1.90
62
1.79
510
1.70
56
2.79
91
2.49
81
2.27
75
2.11
610
1.97
65
1.86
61
1.76
59
2.87
94
2.56
84
2.34
77
2.17
71
2.03
67
1.91
63
1.81
511
3.01
99
2.69
89
2.45
80
2.27
75
2.13
611
2.00
66
1.90
62
3.03
911
2.79
91
2.54
83
2.35
78
2.20
72
2.08
69
1.97
65
2.72
810
2.43
711
2.22
73
2.05
68
1.92
63
1.81
511
1.72
57
2.85
93
2.55
83
2.33
77
2.15
70
2.01
67
1.86
60
1.72
57
2.95
97
2.64
87
2.41
710
2.23
73
2.09
69
1.97
65
1.86
60
3.14
102
2.80
92
2.56
84
2.37
79
2.22
73
2.09
610
1.98
65
3.29
108
2.94
97
2.68
89
2.49
81
2.33
77
2.19
72
2.08
69
3.41
111
3.05
911
2.78
91
2.57
85
2.41
710
2.27
75
2.15
70
3.51
115
3.14
102
2.86
94
2.65
87
2.48
81
2.34
77
2.22
73
3.68
120
3.29
108
3.00
99
2.78
91
2.60
86
2.45
80
2.33
77
3.81
125
3.41
111
3.11
101
2.88
94
2.69
89
2.54
83
2.41
710
3.15
103
2.82
92
2.57
84
2.38
79
2.23
73
2.10
610
1.99
66
3.30
109
2.96
97
2.70
89
2.50
82
2.30
76
2.11
610
1.96
64
3.42
112
3.06
100
2.79
91
2.59
85
2.42
711
2.28
75
2.11
610
3.64
1110
3.25
107
2.97
98
2.75
811
2.57
84
2.43
711
2.30
76
3.82
125
3.41
111
3.12
102
2.88
95
2.70
89
2.54
83
2.41
710
3.95
1210
3.53
116
3.23
106
2.99
99
2.79
91
2.63
87
2.50
82
4.07
133
3.64
1110
3.32
1010
3.07
100
2.88
94
2.71
810
2.57
84
4.27
1311
3.82
125
3.48
114
3.22
106
3.02
910
2.84
93
2.70
89
4.42
145
3.95
1210
3.61
109
3.34
1010
3.12
102
2.95
97
2.79
91
Continued on p. 279
278
APPENDIX A
Tables
Table 16 (continued)
Maximum spans for built-up floor beams supporting not more than two floors1, 2
Commercial
Designation
Northern
Species
Grade
No. 1
and
No. 2
Supported
Length,
m5, 6
ft
2.4
1.94
2.24
2.50
2.37
2.73
3.06
2.75
3.17
3.55
64
73
82
78
811
911
811
104
116
3.0
1.73
2.00
2.24
2.12
2.44
2.73
2.46
2.84
3.17
10
58
66
73
611
711
811
80
93
104
3.6
1.58
1.83
2.04
1.93
2.23
2.50
2.24
2.59
2.90
12
52
511
68
63
73
81
74
85
95
4.2
1.46
1.69
1.89
1.79
2.07
2.31
2.08
2.40
2.68
14
49
56
62
510
69
76
69
710
89
4.8
1.37
1.58
1.77
1.67
1.93
2.16
1.94
2.24
2.51
16
45
52
59
55
63
70
64
74
82
5.4
1.29
1.49
1.67
1.58
1.82
2.04
1.83
2.11
2.36
18
42
410
55
52
511
68
60
611
78
6.0
1.22
1.41
1.58
1.50
1.73
1.93
1.74
2.01
2.24
20
40
47
52
410
58
63
58
66
74
Notes to Table 16
1. Spans apply only where the floors serve residential areas.
2. When the floors have a concrete topping of not more than 51 mm (2 in.), the spans must be multiplied by 0.8.
3. Spans are clear spans between supports. For total span, add two bearing lengths.
4. 3-ply beams with supported lengths greater than 4.2 m (13 ft.8 in.) require 114 mm (412 in.) of bearing. All other beams
require 76 mm (3 in.) bearing.
5. Supported length means half the sum of the joist spans on both sides of the beam.
6. Straight interpolation may be used for other supported lengths.
279
APPENDIX A
Tables
Table 17
Maximum spans for built-up floor beams supporting not more than three floors1, 2
Commercial
Designation
Douglas
Fir Larch
Grade
No. 1
and
No. 2
Hem Fir
No. 1
and
No. 2
Spruce
Pine Fir
No. 1
and
No. 2
Supported
Length,
m5, 6
ft.
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.14
611
1.91
63
1.74
58
1.62
53
1.51
411
1.42
48
1.35
45
2.24
74
2.00
66
1.83
511
1.69
56
1.58
52
1.47
49
1.36
45
2.32
77
2.08
69
1.90
62
1.75
59
1.64
54
1.55
50
1.47
49
2.39
79
2.14
611
1.95
64
1.81
511
1.69
56
1.59
52
1.51
411
2.51
82
2.24
74
2.05
68
1.89
62
1.77
59
1.67
55
1.58
52
2.60
85
2.32
77
2.12
611
1.96
65
1.84
60
1.73
58
1.64
54
2.26
74
2.02
67
1.85
60
1.71
57
1.60
53
1.51
411
1.43
48
2.37
79
2.12
611
1.92
63
1.71
57
1.56
51
1.44
48
1.34
44
2.46
80
2.20
72
2.01
66
1.85
60
1.68
55
1.54
50
1.44
48
2.61
86
2.34
77
2.13
611
1.98
65
1.85
60
1.74
58
1.65
55
2.74
811
2.45
80
2.24
73
2.07
69
1.92
63
1.76
58
1.63
53
2.84
93
2.54
83
2.32
77
2.15
70
2.01
66
1.89
62
1.76
58
2.92
96
2.61
86
2.39
79
2.21
72
2.07
69
1.95
64
1.85
60
3.06
100
2.74
811
2.50
82
2.32
76
2.17
71
2.04
68
1.92
63
3.17
104
2.84
93
2.59
85
2.40
710
2.24
74
2.12
611
2.01
66
2.63
87
2.35
78
2.14
70
1.99
66
1.86
61
1.75
58
1.66
55
2.75
90
2.46
80
2.18
71
1.95
64
1.77
59
1.64
54
1.53
50
2.85
93
2.55
84
2.33
77
2.10
610
1.91
62
1.76
59
1.64
54
3.03
910
2.71
810
2.48
81
2.29
76
2.14
70
2.02
67
1.92
63
3.18
104
2.84
93
2.60
85
2.40
710
2.18
71
2.00
66
1.85
60
3.29
109
2.95
97
2.69
89
2.49
81
2.33
77
2.16
70
2.00
66
3.39
110
3.03
910
2.77
90
2.56
84
2.40
710
2.26
74
2.14
70
3.56
117
3.18
104
2.90
95
2.69
89
2.51
82
2.35
78
2.18
71
3.68
120
3.29
109
3.01
99
2.78
91
2.60
86
2.46
80
2.33
77
Continued on p. 281
280
APPENDIX A
Tables
Table 17 (continued)
Maximum spans for built-up floor beams supporting not more than three floors1, 2
Commercial
Designation
Northern
Species
Grade
No. 1
and
No. 2
Supported
Length,
m5, 6
ft.
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
1.86
61
1.67
55
1.52
411
1.41
47
1.32
43
1.24
41
1.18
310
2.08
69
1.86
61
1.70
56
1.57
51
1.47
410
1.39
46
1.32
43
1.97
65
1.76
59
1.61
53
1.49
410
1.40
46
1.32
43
1.25
41
2.28
75
2.04
68
1.86
61
1.72
57
1.61
53
1.52
411
1.44
48
2.55
83
2.28
75
2.08
69
1.93
63
1.80
510
1.70
56
1.61
53
2.29
75
2.05
68
1.87
61
1.73
58
1.62
53
1.53
50
1.45
49
2.64
87
2.36
78
2.16
70
2.00
66
1.87
61
1.76
59
1.67
55
2.96
97
2.64
87
2.41
710
2.23
73
2.09
610
1.97
65
1.87
61
Notes to Table 17
1. Spans apply only where the floors serve residential areas.
2. When the floors have a concrete topping of not more than 51 mm (2 in.), the spans must be multiplied by 0.8.
3. Spans are clear spans between supports. For total span, add two bearing lengths.
4. 3-ply beams with supported lengths greater than 4.2 m (13 ft.8 in.) require 114 mm (412 in.) of bearing. All other beams
require 76 mm (3 in.) bearing.
5. Supported length means half the sum of the joist spans on both sides of the beam.
6. Straight interpolation may be used for other supported lengths.
281
APPENDIX A
Tables
Table 18
Spans for steel floor beams
Supported Joist Length, m (ft.), (half the sum of joist spans for both sides of the beam)
Section
7 ft.
2.4 m 10 in.
3m
9 ft.
9 in.
11 ft.
3.6 m 9 in.
13 ft.
4.2 m 9 in.
15 ft.
17 ft.
4.8 m 8 in. 5.4 m 8 in.
19 ft.
6.0 m 11 in.
5.5
18-0
5.2
17-1
4.9
16-1
4.8
15-8
4.6
15-1
4.5
14-9
4.3
14-1
W200 x 21
6.5
21-3
6.2
20-3
5.9
19-5
5.7
18-8
5.4
17-8
5.1
16-8
4.9
16-1
W200 x 27
7.3
23-10
6.9
22-7
6.6
21-7
6.3
20-8
6.1
20-0
5.9
19-4
5.8
19-0
W200 x 31
7.8
25-7
7.4
24-3
7.1
23-3
6.8
22-3
6.6
21-7
6.4
21-0
6.2
20-3
W250 x 24
8.1
26-7
7.6
24-10
7.3
23-10
7.0
23-0
6.6
21-7
6.2
20-3
5.9
19-4
W250 x 33
9.2
30-2
8.7
28-6
8.3
27-2
8.0
26-2
7.7
25-3
7.5
24-7
7.3
23-10
W250 x 39
10.0
32-9
9.4
30-9
9.0
29-6
8.6
28-2
8.4
27-7
8.1
26-7
7.9
25-10
W310 x 31
10.4
34-1
9.8
32-1
9.4
30-9
8.9
29-2
8.4
27-7
8.0
26-2
7.6
24-10
W310 x 39
11.4
37-4
10.7 35-1
10.0 32-9
9.8
32-1
9.5
31-2
9.2
30-2
9.0
29-6
4.9
16-1
4.4
14-3
4.1
13-3
3.8
12-6
3.5
12-6
3.4
11-2
3.2
10-6
W200 x 21
5.6
18-4
5.1
16-8
4.6
15-1
4.3
14-1
4.1
13-4
3.8
12-6
3.7
12-1
W200 x 27
6.4
21-0
6.1
20-0
5.6
18-4
5.3
17-4
4.9
16-1
4.7
15-4
4.4
14-4
W200 x 31
6.9
22-7
6.5
21-3
6.2
20-3
5.8
19-0
5.4
17-8
5.1
16-8
4.9
16-1
W250 x 24
6.8
22-3
6.1
20-0
5.6
18-4
5.2
17-1
4.9
16-1
4.6
15-1
4.4
14-4
W250 x 33
8.2
26-10
7.7
25-3
7.0
23-0
6.5
21-3
6.1
20-0
5.8
19-0
5.5
18-0
W250 x 39
8.8
28-10
8.3
27-2
7.8
25-7
7.2
23-7
6.8
22-3
6.4
21-0
6.1
20-0
W310 x 31
8.7
28-6
7.8
25-7
7.2
23-7
6.7
22-0
6.2
20-3
5.9
19-4
5.6
18-4
W310 x 39
10.0
32-9
9.3
30-6
8.5
27-10
7.9
25-10
7.4
24-3
7.0
23-0
6.7
22-0
Note to Table 18
1. The section information provides the beam depth and weight in metric units. For example, a W150 x 22 beam is
150 mm (6 in.) deep and weighs 22 kg. per metre (14.8 lbs. per foot)
282
APPENDIX A
Tables
Table 19
Maximum spans for glue-laminated floor beams 20f-E grade1
Number
of Floors
Supported
1
Beam
Width,
mm
(in.)
80 (3)
130 (5)
80 (3)
Supported
Length,
m6, 7
ft
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
266
1012
304
12
342
1312
380
15
418
1612
456
18
4.32
141
3.87
127
3.53
116
3.27
108
3.06
911
2.88
95
2.73
811
5.51
1711
4.93
160
4.50
148
4.16
137
3.90
128
3.67
1111
3.48
114
3.28
108
2.93
97
2.68
89
2.48
81
2.32
77
2.19
71
2.07
69
5.04
165
4.51
148
4.12
135
3.81
125
3.57
117
3.36
1011
3.19
105
6.43
2011
5.75
189
5.25
171
4.86
1510
4.54
1410
4.28
1311
4.07
133
3.83
125
3.42
112
3.12
102
2.89
95
2.71
810
2.55
84
2.42
711
5.76
189
5.15
169
4.70
154
4.36
142
4.07
133
3.84
126
3.64
1110
7.35
2311
6.57
215
6.00
196
5.55
181
5.19
1611
4.90
1511
4.65
151
4.37
143
3.91
129
3.57
117
3.31
109
3.09
101
2.91
96
2.77
90
6.48
211
5.80
1810
5.29
173
4.90
1511
4.58
1411
4.32
141
4.10
134
8.26
2611
7.39
241
6.75
220
6.25
204
5.84
190
5.51
1711
5.23
170
4.92
160
4.40
144
4.02
131
3.72
121
3.48
114
3.28
108
3.11
102
7.20
235
6.44
210
5.88
192
5.44
179
5.09
167
4.80
158
4.56
1410
9.18
2911
8.21
269
7.50
245
6.94
227
6.49
212
6.12
1911
5.81
1811
5.47
179
4.89
1511
4.46
146
4.13
135
3.86
127
3.64
1110
3.46
113
7.92
259
7.09
231
6.47
211
5.99
196
5.60
183
5.28
172
5.01
164
10.10
3211
9.03
295
8.25
2610
7.64
2410
7.14
233
6.73
2111
6.39
2010
6.01
197
5.38
176
4.91
160
4.54
1410
4.25
1310
4.01
131
3.80
125
8.64
282
7.73
252
7.06
230
6.53
213
6.11
1911
5.76
189
5.47
1710
11.02
3510
9.86
321
9.00
293
8.33
271
7.79
254
7.35
2311
6.97
228
6.56
214
5.87
191
5.36
175
4.96
162
4.64
151
4.37
143
4.15
136
Continued on p. 284
283
APPENDIX A
Tables
Table 19 (continued)
Maximum spans for glue-laminated floor beams 20f-E grade1
Number
of Floors
Supported
2
Beam
Width,
mm
(in.)
130 (5)
80 (3)
130 (5)
Supported
Length,
m6, 7
ft
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
2.4
8
3.0
10
3.6
12
4.2
14
4.8
16
5.4
18
6.0
20
266
1012
304
12
342
1312
380
15
418
1612
456
18
4.18
137
3.74
122
3.41
111
3.16
103
2.96
97
2.79
91
2.64
87
2.75
811
2.46
80
2.24
74
2.08
69
1.94
64
1.83
60
1.74
58
3.50
115
3.13
102
2.86
94
2.65
87
2.48
81
2.34
77
2.22
73
4.88
1510
4.36
142
3.98
130
3.69
120
3.45
113
3.25
107
3.08
100
3.21
105
2.87
94
2.62
86
2.42
711
2.27
75
2.14
611
2.03
67
4.09
134
3.66
1111
3.34
1010
3.09
101
2.89
95
2.72
810
2.58
85
5.57
182
4.99
163
4.55
1410
4.21
139
3.94
1210
3.72
121
3.53
116
3.66
1111
3.28
108
2.99
99
2.77
90
2.59
85
2.44
711
2.32
77
4.67
152
4.18
137
3.81
125
3.53
116
3.30
109
3.11
102
2.95
97
6.27
205
5.61
183
5.12
168
4.74
155
4.43
145
4.18
137
3.97
1211
4.12
135
3.69
120
3.37
1011
3.12
102
2.91
96
2.75
811
2.61
86
5.25
171
4.70
154
4.29
140
3.97
1211
3.72
121
3.50
115
3.32
1010
6.97
228
6.23
203
5.69
186
5.27
172
4.93
160
4.64
151
4.41
144
4.58
1411
4.10
134
3.74
122
3.46
113
3.24
106
3.05
911
2.90
95
5.84
190
5.22
170
4.77
156
4.41
144
4.13
135
3.89
128
3.69
120
7.66
2411
6.85
224
6.26
204
5.79
1810
5.42
178
5.11
168
4.85
159
5.04
165
4.51
148
4.11
135
3.81
125
3.56
117
3.36
1011
3.19
104
6.42
2011
5.74
188
5.24
171
4.85
1510
4.54
149
4.28
1311
4.06
133
8.36
273
7.48
244
6.83
223
6.32
207
5.91
193
5.57
182
5.29
173
5.50
1711
4.92
160
4.49
147
4.15
136
3.89
128
3.66
1111
3.48
114
7.01
2210
6.27
205
5.72
187
5.30
173
4.95
161
4.67
152
4.43
145
Notes to Table 19
1. Spans apply only where the floors serve residential areas.
2. Spans are valid for glue-laminated timber conforming to CAN/CSA-O122-M and CAN/CSA-O177-M.
3. Spans are clear spans between supports. For total span, add two bearing lengths.
4. Provide a minimum bearing length of 89 mm (312 in.).
5. Top edge of beam assumed to be fully laterally supported by joists.
6. Supported length means half the sum of the joist spans on both sides of the beam.
7. Straight interpolation may be used for other supported lengths
284
APPENDIX A
Tables
Table 20
Maximum spans for floor joists general cases1, 2
Maximum Span, m (ft.in.)
Joist Spacing, mm (in.)
Commercial
Designation
Douglas fir larch
(includes Douglas fir
and western larch)
Grade
No. 1
and
No. 2
No. 1
and
No. 2
No. 1
and
No. 2
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
No. 1
and
No. 2
Joist
Size,
mm
in.
300
12
400
16
600
24
300
12
400
16
600
24
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
3.09
102
3.71
122
4.38
144
4.99
165
3.09
10-2
3.71
122
4.38
144
4.99
165
2.92
97
3.54
117
4.17
138
4.75
157
2.51
83
3.19
106
3.76
124
4.29
141
2.91
97
3.53
117
4.16
138
4.75
157
2.91
97
3.53
117
4.16
138
4.75
157
2.71
811
3.36
110
3.96
130
4.52
1410
2.33
78
3.04
100
3.58
119
4.08
135
2.62
87
3.36
110
3.96
130
4.52
1410
2.62
87
3.36
110
3.96
130
4.52
1410
2.49
82
3.20
106
3.77
124
4.30
141
2.16
71
2.84
94
3.41
112
3.88
129
3.29
1010
4.00
131
4.66
153
5.26
172
3.29
1010
4.00
131
4.66
153
5.26
172
3.14
104
3.81
125
4.44
146
5.01
164
2.83
93
3.44
113
4.01
131
4.53
149
2.99
910
3.76
124
4.38
144
4.94
162
2.99
910
3.76
124
4.38
144
4.94
162
2.85
94
3.58
119
4.17
138
4.71
155
2.57
85
3.23
107
3.77
124
4.25
1311
2.62
87
3.44
113
4.11
136
4.65
153
2.62
87
3.44
113
4.11
136
4.65
153
2.49
82
3.27
109
3.92
1210
4.42
146
2.25
75
2.96
98
3.54
117
4.00
131
With Strapping
With Bridging
With Strapping
and Bridging
300
400
600
12
16
24
3.29
1010
4.19
139
4.84
1510
5.43
1710
3.29
1010
4.19
139
4.84
1510
5.43
1710
3.14
104
3.99
131
4.60
151
5.17
170
2.83
94
3.60
1110
4.16
138
4.67
154
2.99
910
3.90
1210
4.51
1410
5.06
167
2.99
910
3.90
1210
4.51
1410
5.06
167
2.85
94
3.72
122
4.29
141
4.82
1510
2.57
85
3.36
110
3.88
129
4.35
144
2.62
87
3.44
113
4.20
1310
4.72
156
2.62
87
3.44
113
4.20
1310
4.72
156
2.49
82
3.27
109
4.00
132
4.49
149
2.25
75
2.96
98
3.62
1110
4.06
134
Note to Table 20
1. Spans apply only where the floors serve residential areas.
2. Subfloor must comply with minimum requirements from Tables 18 and 19.
285
APPENDIX A
Tables
Table 21
Maximum spans for floor joists special cases1, 2
Commercial
Designation
Douglas fir larch
(includes Douglas fir
and western larch)
Grade
No. 1
and
No. 2
No. 1
and
No. 2
No. 1
and
No. 2
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
No. 1
and
No. 2
Joist
Size,
mm
in.
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
38 x 140
2x6
38 x 184
2x8
38 x 235
2 x 10
38 x 286
2 x 12
2.99
9-10
3.83
12-7
4.50
14-9
5.12
16-10
2.99
9-10
3.83
12-7
4.50
14-9
5.12
16-10
2.85
9-4
3.64
11-11
4.28
14-1
4.88
16-0
2.57
8-5
3.29
10-10
3.87
12-8
4.40
14-5
2.62
8-7
3.44
11-3
4.11
13-6
4.68
15-4
2.62
8-7
3.44
11-3
4.11
13-6
4.68
15-4
2.49
8-2
3.27
10-9
3.91
12-10
4.46
14-7
2.25
7-5
2.96
9-8
3.54
11-7
4.03
13-2
3.29
10-10
4.33
14-2
5.24
17-2
5.93
19-5
3.29
10-10
4.33
14-2
5.24
17-2
5.93
19-5
3.14
10-4
4.12
13-6
4.99
16-4
5.65
18-6
2.83
9-4
3.72
12-3
4.51
14-9
5.10
16-9
2.99
9-10
3.93
12-11
4.98
16-4
5.64
18-6
2.99
9-10
3.93
12-11
4.98
16-4
5.64
18-6
2.85
9-4
3.75
12-4
4.75
15-7
5.37
17-7
2.57
8-5
3.38
11-1
4.29
14-1
4.85
15-11
2.62
8-7
3.44
11-3
4.31
14-2
5.00
16-5
2.62
8-7
3.44
11-3
4.39
14-5
5.25
17-3
2.49
8-2
3.27
10-9
4.18
13-9
5.06
16-7
2.25
7-5
2.96
9-8
3.76
12-4
4.36
14-4
3.29
10-10
4.33
14-2
5.37
17-8
6.24
20-6
3.29
10-10
4.33
14-2
5.53
18-2
6.54
21-6
3.14
10-4
4.12
13-6
5.27
17-3
6.23
20-5
2.83
9-4
3.72
12-3
4.69
15-4
5.44
17-10
2.99
9-10
3.81
12-6
4.65
15-3
5.40
17-9
2.99
9-10
3.93
12-11
4.88
16-0
5.66
18-7
2.85
9-4
3.75
12-4
4.79
15-8
5.81
19-1
2.57
8-5
3.32
10-11
4.06
13-4
4.71
15-5
2.55
8-5
3.11
10-2
3.80
12-6
4.41
14-6
2.62
8-7
3.26
10-8
3.99
13-1
4.63
15-2
2.49
8-2
3.27
10-9
4.13
13-7
4.79
15-9
2.23
7-4
2.71
8-11
3.31
10-10
3.84
12-7
Notes to Table 21
1. Spans apply only where the floors serve residential areas.
2. Subfloor must comply with minimum requirements from Tables 18 and 19.
3. No bridging is assumed for spans for floor joists with concrete topping.
286
APPENDIX A
Tables
Table 22
Minimum thickness of subflooring
Minimum Subflooring Thickness, mm (in.),
for Maximum Joist Spacing at
400 (16)
500 (20)
600 (24)
15.5 (58)
15.5 (58)
18.5 (2332)
15.9 (58)
15.9 (58)
19.0 (34)
Particleboard
15.9 (58)
19.0 (34)
25.4 (1)
1F16
1F20
1F24
2F16
2F20
2F24
Lumber
17.0 (1116)
19.0 (34)
19.0 (34)
Table 23
Sheathing and subfloor attachment
Minimum Length of Fasteners for Sheathing
and Subfloor Attachment, mm (in.)
Element
Common
or Spiral
Nails
Ring Thread
Nails or
Screws
Roofing
Nails
Staples
Minimum No. or
Maximum Spacing
of Fasteners
51 (2)
45 (134)
N/A
38 (112)
51 (2)
45 (134)
N/A
51 (2)
57 (214)
51 (2)
N/A
N/A
Fibreboard sheathing up to
13 mm (12 in.) thick
N/A
N/A
44 (134)
28 (118)
Gypsum sheathing up to
13mm (12 in.) thick
N/A
N/A
44 (134)
N/A
51 (2)
45 (134)
N/A
51 (2)
2 per support
51 (2)
45 (134)
N/A
51 (2)
3 per support
287
APPENDIX A
Tables
Table 24
Nailing for framing1
Construction Detail
Minimum Length
of Nails, mm (in.)
Minimum Number or
Maximum Spacing of Nails
82
(314)
57
(214)
57
(214)
2 at each end
76
(3)
76
(3)
82
(314)
2 per joist
76
(3)
2 at each end
82
101
(314)
(4)
5
3
82
101
(314)
(4)
5
3
63
82
(212)
(314)
4
2
76
(3)
76
(3)
82
(314)
82
(314)
82
(314)
Lintels to studs
82
(314)
2 at each end
82
(314)
82
(314)
3
Continued on p. 289
288
APPENDIX A
Tables
Table 24 (continued)
Nailing for framing1
Minimum Length
of Nails, mm (in.)
Construction Detail
Minimum Number or
Maximum Spacing of Nails
101
(4)
76
(3)
76
(3)
See Table 30
57
(214)
82
(314)
76
(3)
57
(214)
82
(314)
76
(3)
82
(314)
82
(314)
82
(314)
76
(3)
76
(3)
Note to Table 24
1. Where the bottom wall plate or sole plate of an exterior wall is not nailed to joists or blocking, the exterior wall is
permitted to be fastened to the floor framing by plywood, OSB, or waferboard sheathing that extends down over the
floor framing and is fastened to that framing by nails or staples. The wall can also be fastened by tying the wall framing to
the floor framing with galvanized strips that are 50 mm (2 in.) wide, 0.41 mm (0.016 in.) in thickness or more, spaced not
more than 1.2 m (48 in.) apart and fastened at each end with at least two 63 mm (212 in.) nails.
289
APPENDIX A
Tables
Table 25
Size and spacing of studs
Type of
Wall
Interior
Exterior
Supported Loads
(including dead loads)
Minimum
Stud Size
mm (in.)
Maximum
Stud Spacing,
mm (in.)
Maximum
Unsupported
Height m (ft.in.)
No load
38 x 38 (2 x 2)
38 x 89 (2 x 4) flat1
400 (16)
400 (16)
2.4 (80)
3.6 (1110)
38 x 64 (2 x 3)
38 x 64 (2 x 3) flat1
38 x 89 (2 x 4)
38 x 89 (2 x 4) flat1
600 (24)
400 (16)
600 (24)
400 (16)
3.0 (910)
2.4 (80)
3.6 (1110)
2.4 (80)
38 x 89 (2 x 4)
400 (16)
3.6 (1110)
Roof load
Attic accessible by a stairway
Attic not accessible by a
stairway plus one floor
38 x 64 (2 x 3)
38 x 89 (2 x 4)
400 (16)
600 (24)
2.4 (80)
3.6 (1110)
38 x 89 (2 x 4)
38 x 140 (2 x 6)
300 (12)
400 (16)
3.6 (1110)
4.2 (139)
38 x 140 (2 x 6)
300 (12)
4.2 (139)
38 x 64 (2 x 3)
38 x 89 (2 x 4)
400 (16)
600 (24)
2.4 (80)
3.0 (910)
38 x 89 (2 x 4)
38 x 140 (2 x 6)
400 (16)
600 (24)
3.0 (910)
3.0 (910)
38 x 89 (2 x 4)
38 x 140 (2 x 6)
300 (12)
400 (16)
3.0 (910)
3.6 (1110)
38 x 140 (2 x 6)
300 (12)
1.8 (60)
Note to Table 25
1. Studs on the flat are permitted to be used in gable ends of roofs that contain only unfinished space or in non-loadbearing
interior walls within the limits described in the National Building Code of Canada. Studs supporting only a load from an attic
not accessible from a stairway are permitted to be placed on the flat, in accordance with this table, if they are clad on not
less than one side with plywood, OSB, or waferboard sheathing fastened to the face of the studs with a structural adhesive,
and if the portion of the roof supported by the studs does not exceed 2.1 m (6 ft.10 in.) in width.
290
APPENDIX A
Tables
Table 26
Maximum spans for spruce, pine or fir lintels No. 1 or No. 2 grade
non-structural sheathing7
Lintel
Supporting
Limited attic
storage and
ceiling
Lintel Supporting
Roof and ceiling
only (tributary
width 0.6 m
(2 ft.))6
Lintel Supporting
Roof and ceiling
only (tributary
width 4.9 m
(16 ft. 0 in.))1
Lintel Supporting
Roof, ceiling and
1 storey1,2,5
Lintel Size,
mm
in.4
2-ply
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
1.0
20.9
Interior
Walls
2.55
8-4
4.01
13-2
5.27
17-4
6.37
20-11
7.38
24-3
1.27
4-2
1.93
6-4
2.35
7-9
2.88
9-5
3.34
11-0
1.05
3-5
1.49
4-11
1.82
6-0
2.22
7-3
2.58
8-5
2.23
7-4
3.50
11-6
4.61
15-1
5.76
18-11
6.67
21-11
1.11
3-8
1.66
5-5
2.02
6-8
2.47
8-1
2.87
9-5
0.96
3-2
1.37
4-6
1.67
5-6
2.04
6-8
2.36
7-9
2.02
6-8
3.18
10-5
4.18
13-9
5.34
17-6
6.21
20-4
1.01
3-4
1.48
4-10
1.80
5-11
2.20
7-3
2.56
8-5
0.89
2-11
1.27
4-2
1.55
5-1
1.89
6-2
2.15
7-1
1.88
6-2
2.96
9-8
3.88
12-9
4.96
16-3
5.87
19-3
0.93
3-1
1.35
4-5
1.64
5-5
2.01
6-7
2.33
7-8
0.84
2-9
1.19
3-11
1.44
4-9
1.73
5-8
1.96
6-5
1.77
5-10
2.78
9-2
3.66
12-0
4.67
15-4
5.61
18-5
0.87
2-10
1.25
4-1
1.52
5-0
1.84
6-1
2.09
6-10
0.79
2-7
1.13
3-8
1.33
4-4
1.59
5-3
1.81
5-11
1.27
42
1.93
64
2.35
79
2.88
95
3.34
110
1.88
6-2
2.96
9-8
3.88
12-9
4.96
16-3
5.87
19-3
0.93
3-1
1.35
4-5
1.64
5-5
2.01
6-7
2.33
7-8
0.74
2-5
1.02
3-4
1.20
3-11
1.45
4-9
1.66
5-5
Continued on p. 292
291
APPENDIX A
Tables
Table 26 (continued)
Maximum spans for spruce, pine or fir lintels No. 1 or No. 2 grade
non-structural sheathing7
Lintel
Supporting
Lintel Supporting
Roof ceiling and
2 storeys1,2,5
Lintel Supporting
Roof ceiling and
3 storeys1,2,5
Lintel Size,
mm
in.4
2-ply
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
2-38 x 89
2-2 x 4
2-38 x 140
2-2 x 6
2-38 x 184
2-2 x 8
2-38 x 235
2-2 x 10
2-38 x 286
2-2 x 12
1.0
20.9
0.94
3-1
1.34
4-5
1.63
5-4
1.99
6-6
2.31
7-7
0.88
2-11
1.25
4-1
1.52
5-0
1.86
6-1
2.11
6-11
0.83
2-9
1.19
3-11
1.44
4-9
1.72
5-8
1.96
6-5
0.80
2-7
1.14
3-9
1.35
4-5
1.62
5-4
1.84
6-1
0.79
2-7
1.13
3-8
1.33
4-4
1.60
5-3
1.82
6-0
0.77
2-6
1.08
3-7
1.27
4-2
1.53
5-0
1.74
5-9
Interior
Walls
0.76
2-6
1.06
3-6
1.25
4-1
1.50
4-11
1.71
5-7
0.74
2-5
1.02
3-4
1.21
3-11
1.45
4-9
1.66
5-5
0.64
2-1
0.88
2-11
1.05
3-5
1.27
4-2
1.45
4-9
0.59
1-11
0.81
2-8
0.97
3-2
1.17
3-10
1.35
4-5
Notes to Table 26
1. Lintel spans are calculated based on a maximum floor joist, roof joist or rafter span of 4.9 m (16 ft.0 in.) and a maximum
roof truss span of 9.8 m (32 ft.0 in.). Lintel spans may be increased by 5 per cent if rafter and joist spans are no greater
than 4.3 m (14 ft.1 in.), and roof truss spans are no greater than 8.6 m (28 ft.3 in.). Spans may be increased by 10 per cent
if rafter and joist spans are no greater than 3.7 m (12 ft.2 in.), and roof truss spans are no greater than 7.4 m (24 ft.3 in.).
2. If floor joists span the full width of the building without support, lintel spans shall be reduced by 15 per cent for Roof,
ceiling and 1 storey, by 20 per cent for Roof, ceiling and 2 storeys and by 25 per cent for Roof, ceiling and 3 storeys.
3. For ends of lintels fully supported by walls, provide minimum 38 mm (112 in.) of bearing for lintel spans up to 3 m (10 ft.),
or minimum 76 mm (3 in.) of bearing for lintel spans greater than 3 m (10 ft.).
4. A single piece of 89 mm (312 in.) thick lumber may be used in lieu of 2 pieces of 38 mm (112 in.) thick lumber on edge.
5. Spans apply only where the floors serve residential areas.
6. Spans for 0.6 m (2 ft.) tributary width are calculated for lintels in end walls that support only a 0.6 m (2 ft.) width of roof
and ceiling, but do not support roof joists, roof rafters or roof trusses.
7. When structural sheathing is used, lintel spans may be increased by 15 per cent. Structural sheathing consists of a minimum
9.5 mm (38 in.) thick structural panel conforming to CSA O121, CSA O151, CSA O437 or CSA O325 fastened with
at least two rows of fasteners conforming to Table 20 to the exterior face of the lintel, and a single row to the top
plates and studs.
292
APPENDIX A
Tables
Table 27
Maximum spans for built-up ridge beams and lintels supporting roof and ceiling
only. No. 1 or No. 2 grade
Maximum Span, m (ft.in.)1, 2,3
Commercial
Designation
Spruce, pine, or fir
(includes Spruce
[all species except
Coast Sitka
Spruce], Jack Pine,
Lodgepole Pine,
Balsam Fir and
Alpine Fir)
Lintel Size,
mm
1.0
1.5
2.0
2.5
3.0
in.
20.9
31.3
41.8
52.2
62.7
3-ply
38 x 184
2x8
4-ply
5-ply
3-ply
38 x 235
2 x 10
4-ply
5-ply
3-ply
38 x 286
2 x 12
4-ply
5-ply
2.88
2.48
2.21
2.01
1.86
96
82
73
67
61
3.30
2.86
2.55
2.32
2.14
1010
95
84
77
70
3.55
3.10
2.82
2.59
2.40
118
102
93
86
710
3.53
3.03
2.70
2.46
2.27
117
911
810
81
75
4.07
3.50
3.12
2.84
2.62
134
116
103
94
87
4.54
3.91
3.43
3.17
2.93
1411
1210
115
105
97
4.09
3.52
3.13
2.85
2.63
139
116
103
94
88
4.72
4.06
3.62
3.29
3.04
156
134
1110
1010
100
5.28
4.54
4.04
3.68
3.40
174
1411
133
121
112
Notes to Table 27
1. Beam and lintel spans are calculated based on a maximum supported length of 4.9 m (16 ft.0 in.). Spans may be increased
by 5 per cent for supported lengths not more than 4.3 m (14 ft.1 in.), by 10 per cent for supported lengths not more than
3.7 m (12 ft.2 in.) and by 25 per cent for supported lengths not more than 2.4 m (7 ft.10 in.).
2. For ridge beams, supported length means half the sum of the rafter, joist or truss span on both sides of the beam. For lintels,
supported length means half the sum of truss, roof joist or rafter spans supported by the lintel plus the length of the
overhang beyond the lintel.
3. Provide minimum 76 mm (3 in.) bearing.
293
APPENDIX A
Tables
Table 28
Minimum thickness of wall sheathing
Minimum Thickness, mm (in.)
Type of Sheathing
With Supports
400 (16) o.c.
With Supports
500 (20) o.c.
With Supports
600 (24) o.c.
Material Standards
Structural
Fibreboard (insulating)
9.5 (38)
11.1 (716)
CAN/CSA-A247
Gypsum sheathing
9.5 (38)
12.7 (12)
CAN/CSA-A82.27-M
6.0 (14)
7.5 (516)
CSA O121-M
CSA O151-M
CSA O153-M
6.35 (14)
7.9 (516)
CSA O437.0
Panel mark
(performance-rated panels)
W16
W20
W24
CSA O325.0
Lumber
17.0 (1116)
17.0 (1116)
See Table 7
Mineral fibre,
rigid board, type 2
25 (1)
25 (1)
CSA A101-M
6.0 (14)
7.5 (516)
CSA O437.0
Phenolic, faced
25 (1)
25 (1)
CAN/CGSB-51.25-M
Non-Structural
Expanded polystyrene
(Types 1 and 2)
38 (112)
38 (112)
CAN/CGSB-51.20-M
Expanded polystyrene
(Types 3 and 4)
25 (1)
25 (1)
CAN/CGSB-51.20-M
38 (112)
38 (112)
CGSB 51-GP-21M
25 (1)
25 (1)
CGSB 51-GP-21M
25 (1)
25 (1)
CAN/CGSB-51.26-M
294
APPENDIX A
Tables
Table 29
Maximum spans for roof joists specified roof snow loads 1.0 to 2.0 kPa
(20.9 to 41.8 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Douglas fir larch
(includes Douglas
fir and western
larch)
Hem fir
(includes western
hemlock and
amabilis fir)
1.0
(20.9)
1.5
(31.3)
2.0
(41.8)
Joist Spacing,
mm (in.)
Joist Spacing,
mm (in.)
Joist Spacing,
mm (in.)
Joist
Size,
mm
300
400
600
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
2.59
2.36
2.06
2.27
2.06
1.80
2.06
1.87
1.63
2x4
86
79
69
75
69
511
69
62
54
38 x 140
4.08
3.71
3.24
3.57
3.24
2.83
3.24
2.94
2.57
2x6
135
122
108
118
108
93
108
98
85
38 x 184
5.36
4.87
4.26
4.69
4.26
3.72
4.26
3.87
3.38
2x8
177
160
140
154
140
122
140
128
111
38 x 235
6.85
6.22
5.44
5.98
5.44
4.74
5.44
4.94
4.22
2 x 10
226
205
1710 198
1710 157
1710 162
1310
38 x 286
8.34
7.57
6.40
6.62
5.50
6.62
6.00
4.90
2 x 12
274
2410 210
2311 219
181
219
198
161
38 x 89
2.59
2.36
2.06
2.27
2.06
1.80
2.06
1.87
1.63
2x4
86
79
69
75
69
511
69
62
54
38 x 140
4.08
3.71
3.24
3.57
3.24
2.83
3.24
2.94
2.57
2x6
135
122
108
118
108
93
108
98
85
38 x 184
5.36
4.87
4.26
4.69
4.26
3.72
4.26
3.87
3.38
2x8
177
160
140
154
140
122
140
128
111
38 x 235
6.85
6.22
5.44
5.98
5.44
4.75
5.44
4.94
4.32
2 x 10
226
205
1710 198
1710 157
1710 162
142
38 x 286
8.34
7.57
6.62
6.62
6.62
6.01
5.25
2 x 12
274
2410 219
1811 219
199
1610
No. 1
and
No. 2
7.28
7.28
2311 219
5.77
Continued on p. 296
295
APPENDIX A
Tables
Table 29 (continued)
Maximum spans for roof joists specified roof snow loads 1.0 to 2.0 kPa
(20.9 to 41.8 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Spruce, pine, or fir
(includes spruce
[all species except
coast sitka
spruce], jack pine,
lodgepole pine,
balsam fir and
alpine fir)
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
1.0
(20.9)
1.5
(31.3)
2.0
(41.8)
Joist Spacing,
mm (in.)
Joist Spacing,
mm (in.)
Joist Spacing,
mm (in.)
Joist
Size,
mm
300
400
600
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
2.47
2.24
1.96
2.16
1.96
1.71
1.96
1.78
1.56
2x4
81
74
65
71
65
57
65
510
51
38 x 140
3.89
3.53
3.08
3.40
3.08
2.69
3.08
2.80
2.45
2x6
129
117
101
112
101
810
101
92
80
38 x 184
5.11
4.64
4.05
4.46
4.05
3.54
4.05
3.68
3.22
2x8
169
153
134
148
134
117
134
121
107
38 x 35
6.52
5.93
5.18
5.70
5.18
4.52
5.18
4.70
4.11
2 x 10
215
195
170
188
170
1410 170
155
136
38 x 286
7.94
7.21
6.30
6.94
6.30
5.50
6.30
5.73
5.00
2 x 12
261
238
208
229
208
181
208
189
165
38 x 89
2.23
2.03
1.77
1.95
1.77
1.55
1.77
1.61
1.41
2x4
74
68
510
65
510
51
510
53
47
38 x 140
3.51
3.19
2.79
3.07
2.79
2.43
2.79
2.53
2.21
2x6
116
106
92
101
92
80
92
84
73
38 x 184
4.61
4.19
3.66
4.03
3.66
3.20
3.66
3.33
2.91
2x8
152
139
120
133
120
106
120
1011 96
38 x 235
5.89
5.35
4.68
5.15
4.68
4.09
4.68
4.25
2 x 10
194
177
154
1611 154
135
154
1311 121
38 x 286
7.17
6.52
5.58
6.26
5.69
4.80
5.69
5.17
4.27
2 x 12
236
215
184
207
188
159
188
170
140
No. 1
and
No. 2
3.68
Note to Table 29
1. To determine the specified snow load in your location, contact your municipal building department.
296
APPENDIX A
Tables
Table 30
Maximum spans for roof joists specified roof snow loads 2.5 and 3.0 kPa
(52.2 and 62.7 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Douglas fir larch
(includes Douglas
fir and western
larch)
Hem fir
(includes western
hemlock and
amabilis fir)
2.5 (52.2)
3.0 (62.7)
Joist
Size,
mm
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
1.91
1.74
1.52
1.80
1.63
1.43
2x4
63
58
50
511
54
48
38 x 140
3.01
2.73
2.39
2.83
2.57
2.25
2x6
910
90
710
93
85
74
38 x 184
3.95
3.59
3.14
3.72
3.38
2.90
2x8
130
119
103
122
111
96
38 x 235
5.05
4.59
3.84
4.75
4.32
3.55
2 x 10
167
151
127
157
142
118
38 x 286
6.14
5.46
4.46
5.78
5.05
4.12
2 x 12
202
1711
148
190
167
136
38 x 89
1.91
1.74
1.52
1.80
1.63
1.43
2x4
63
58
50
511
54
48
38 x 140
3.01
2.73
2.39
2.83
2.57
2.25
2x6
910
90
710
93
85
74
38 x 184
3.95
3.59
3.14
3.72
3.38
2.95
2x8
130
119
103
122
111
98
38 x 235
5.05
4.59
4.01
4.75
4.32
3.72
2 x 10
167
151
132
157
142
123
38 x 286
6.14
5.58
4.68
5.78
5.25
4.32
2 x 12
202
184
154
190
173
142
No. 1
and
No. 2
Continued on p. 298
297
APPENDIX A
Tables
Table 30 (continued)
Maximum spans for roof joists specified roof snow loads 2.5 and 3.0 kPa
(52.2 and 62.7 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Spruce, pine, or fir
(includes spruce
[all species except
coast sitka
spruce], jack pine,
lodgepole pine,
balsam fir and
alpine fir)
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
2.5 (52.2)
3.0 (62.7)
Joist Spacing,
mm (in.)
Joist Spacing,
mm (in.)
Joist
Size,
mm
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
1.82
1.65
1.44
1.71
1.56
1.36
2x4
60
55
49
57
51
46
38 x 140
2.86
2.60
2.27
2.69
2.45
2.14
2x6
95
86
75
810
80
70
38 x 184
3.76
3.42
2.99
3.54
3.22
2.81
2x8
124
113
910
117
107
93
38 x 235
4.81
4.37
3.82
4.52
4.11
3.59
2 x 10
159
144
126
1410
136
119
38 x 286
5.85
5.31
4.64
5.50
5.00
4.37
2 x 12
192
175
153
181
165
144
38 x 89
1.64
1.49
1.31
1.55
1.41
1.23
2x4
55
411
43
51
47
40
38 x 140
2.59
2.35
2.05
2.43
2.21
1.93
2x6
86
79
69
80
73
64
38 x 184
3.40
3.09
2.70
3.20
2.91
2.53
2x8
112
102
810
106
96
84
38 x 235
4.34
3.94
3.35
4.09
3.71
3.10
2 x 10
143
1211
110
135
122
102
38 x 286
5.28
4.76
3.89
4.97
4.40
3.59
2 x 12
174
157
129
164
145
119
No. 1
and
No. 2
Note to Table 30
1. To determine the specified snow load in your location, contact your municipal building department.
298
APPENDIX A
Tables
Table 31
Maximum spans for roof rafters specified roof snow loads 1.0 to 2.0 kPa
(20.9 to 41.8 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Douglas fir larch
(includes Douglas
fir and western
larch)
Hem fir
(includes western
hemlock and
amabilis fir)
1.0
(20.9)
1.5
(31.3)
2.0
(41.8)
Rafter Spacing,
mm (in.)
Rafter Spacing,
mm (in.)
Rafter Spacing,
mm (in.)
Rafter
Size,
mm
300
400
600
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
3.27
2.97
2.59
2.86
2.59
2.27
2.59
2.36
2.06
2x4
109
99
86
94
86
75
86
79
69
38 x 140
5.14
4.67
3.95
4.49
4.08
3.34
4.08
3.60
2.94
2x6
1610 154
1211 149
135
1011 135
1110 98
38 x 184
6.76
5.88
4.80
5.74
4.97
4.06
5.06
4.38
3.58
2x8
222
194
159
1810 164
134
167
145
119
38 x 235
8.30
7.19
5.87
7.02
6.08
4.96
6.19
5.36
4.38
2 x 10
273
237
193
230
1911 163
204
177
144
38 x 286
9.63
8.34
6.81
8.14
7.05
5.76
7.18
6.22
5.08
2 x 12
317
275
224
269
232
1811 237
205
168
38 x 89
3.27
2.97
2.59
2.86
2.59
2.27
2.59
2.36
2.06
2x4
109
99
86
94
86
75
86
79
69
38 x 140
5.14
4.67
4.08
4.49
4.08
3.50
4.08
3.71
3.08
2x6
1610 154
135
149
135
116
135
122
101
38 x 184
6.76
6.14
5.04
5.90
5.21
4.26
5.31
4.60
3.75
2x8
222
202
166
194
171
140
175
151
124
38 x 235
8.63
7.54
6.16
7.36
6.37
5.20
6.49
5.62
4.59
2 x 10
284
249
202
242
2011 171
214
185
151
38 x 286
10.11
8.75
7.15
8.54
7.40
6.04
7.53
6.52
5.33
2 x 12
332
289
235
280
243
1910 249
215
176
No. 1
and
No. 2
Continued on p. 300
299
APPENDIX A
Tables
Table 31 (continued)
Maximum spans for roof rafters specified roof snow loads 1.0 to 2.0 kPa
(20.9 to 41.8 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Spruce, pine, or fir
(includes spruce
[all species except
coast sitka
spruce], jack pine,
lodgepole pine,
balsam fir and
alpine fir)
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
Grade
1.0
(20.9)
1.5
(31.3)
2.0
(41.8)
Rafter Spacing,
mm (in.)
Rafter Spacing,
mm (in.)
Rafter Spacing,
mm (in.)
Rafter
Size,
mm
300
400
600
300
400
600
300
400
600
in.
12
16
24
12
16
24
12
16
24
3.11
2.83
2.47
2.72
2.47
2.16
2.47
2.24
1.96
103
93
81
811
81
71
81
74
65
38 x 140
4.90
4.45
3.89
4.28
3.89
3.40
3.89
3.53
3.08
2x6
161
147
129
140
129
112
129
117
101
38 x 184
6.44
5.85
5.11
5.62
5.11
4.41
5.11
4.64
3.89
2x8
211
192
169
185
169
146
169
153
129
38 x 235
8.22
7.47
6.38
7.18
6.52
5.39
6.52
5.82
4.75
2 x 10
270
246
2011 237
215
178
215
191
157
38 x 286
10.00
9.06
7.40
8.74
7.66
6.25
7.80
6.76
5.52
2 x 12
3210 299
243
288
252
206
257
222
181
2.81
2.55
2.23
2.46
2.23
1.95
2.23
2.03
1.77
93
85
74
81
74
65
74
68
510
38 x 140
4.42
4.02
3.44
3.86
3.51
2.91
3.51
3.14
2.56
2x6
146
132
113
128
116
96
116
104
85
38 x 184
5.81
5.13
4.19
5.00
4.33
3.54
4.41
3.82
3.12
2x8
191
1610 139
165
143
117
146
126
103
38 x 235
7.24
6.27
5.12
6.12
5.30
4.33
5.40
4.67
3.82
2 x 10
239
207
1610 201
175
142
178
154
126
38 x 286
8.40
7.27
5.94
7.10
6.15
5.02
6.26
5.42
4.43
2 x 12
277
2310 196
233
202
166
206
179
146
No. 1 38 x 89
and
No. 2 2 x 4
No. 1 38 x 89
and
No. 2 2 x 4
Note to Table 31
1. To determine the specified snow load in your location, contact your municipal building department.
300
APPENDIX A
Tables
Table 32
Maximum spans for roof rafters specified roof snow loads 2.5 and 3.0 kPa
(52.2 and 62.7 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Douglas fir
larch (includes
Douglas fir and
western larch)
Hem fir
(includes western
hemlock and
amabilis fir)
2.5 (52.2)
3.0 (62.7)
Rafter
Size,
mm
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
2.41
2.19
1.86
2.27
2.06
1.71
2x4
711
72
61
75
69
57
38 x 140
3.76
3.26
2.66
3.46
3.00
2.45
2x6
124
108
89
114
910
80
38 x 184
4.58
3.96
3.24
4.21
3.65
2.98
2x8
150
130
107
1310
120
99
38 x 235
5.60
4.85
3.96
5.15
4.46
3.64
2 x 10
184
1511
130
1611
148
1111
38 x 286
6.50
5.63
4.59
5.98
5.17
4.23
2 x 12
214
185
151
197
170
1310
38 x 89
2.41
2.19
1.91
2.27
2.06
1.80
2x4
711
72
63
75
69
511
38 x 140
3.79
3.42
2.79
3.57
3.14
2.57
2x6
125
113
92
118
104
85
38 x 184
4.80
4.16
3.40
4.42
3.83
3.12
2x8
159
138
112
146
127
103
38 x 235
5.87
5.08
4.15
5.40
4.68
3.82
2 x 10
193
168
137
179
154
126
38 x 286
6.81
5.90
4.82
6.27
5.43
4.43
2 x 12
224
194
1510
207
1710
146
No. 1
and
No. 2
Continued on p. 302
301
APPENDIX A
Tables
Table 32 (continued)
Maximum spans for roof rafters specified roof snow loads 2.5 and 3.0 kPa
(52.2 and 62.7 psf)
Maximum Span, m (ft.in.)
Specified Snow Load, kPa (psf)1
Commercial
Designation
Spruce, pine, or fir
(includes spruce
[all species except
coast sitka spruce],
jack pine, lodgepole
pine, balsam fir and
alpine fir)
Northern species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
2.5 (52.2)
3.0 (62.7)
Rafter
Size,
mm
300
400
600
300
400
600
Grade
in.
12
16
24
12
16
24
No. 1
and
No. 2
38 x 89
2.29
2.08
1.82
2.16
1.96
1.71
2x4
76
610
60
71
65
57
38 x 140
3.61
3.28
2.86
3.40
3.08
2.66
2x6
1110
109
95
112
101
89
38 x 184
4.74
4.31
3.52
4.46
3.96
3.23
2x8
157
142
116
148
130
107
38 x 235
6.06
5.27
4.30
5.59
4.84
3.96
2 x 10
1910
173
141
184
1511
130
38 x 286
7.06
6.11
4.99
6.49
5.62
4.59
2 x 12
232
201
164
214
185
151
38 x 89
2.07
1.88
1.62
1.95
1.77
1.49
2x4
610
62
54
65
510
411
38 x 140
3.26
2.84
2.32
3.02
2.61
2.13
2x6
108
94
77
911
87
70
38 x 184
3.99
3.46
2.82
3.67
3.18
2.60
2x8
131
114
93
121
105
86
38 x 235
4.88
4.23
3.45
4.49
3.89
3.17
2 x 10
160
1310
114
149
129
105
38 x 286
5.66
4.90
4.00
5.21
4.51
3.68
2 x 12
187
161
132
171
1410
121
No. 1
and
No. 2
Note to Table 32
1. To determine the specified snow load in your location, contact your municipal building department.
302
APPENDIX A
Tables
Table 33
Maximum spans for ceiling joists attic not accessible by a stairway
Maximum Span, m (ft.in.)
Commercial
Designation
Douglas fir larch
(includes Douglas
fir and western
larch)
Hem fir
(includes western
hemlock and
amabilis fir)
Northern Species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules)
Grade
No. 1
and
No. 2
No. 1
and
No. 2
No. 1
and
No. 2
No. 1
and
No. 2
Joist Size,
mm (in.)
(12)
400 (16)
600 (24)
38 x 89
(2 x 4)
3.27
(109)
2.97 (99)
2.59 (86)
38 x 140
(2 x 6)
5.14
(1610)
4.67 (154)
4.08 (135)
38 x 184
(2 x 8)
6.76
(222)
6.14 (202)
5.36 (177)
38 x 235
(2 x 10)
8.63
(284)
7.84 (259)
6.85 (226)
38 x 286
(2 x 12)
10.50 (345)
9.54 (313)
8.34 (274)
38 x 89
(2 x 4)
3.27
(109)
2.97 (99)
2.59 (86)
38 x 140
(2 x 6)
5.14
(1610)
4.67 (154)
4.08 (135)
38 x 184
(2 x 8)
6.76
(222)
6.14 (202)
5.36 (177)
38 x 235
(2 x 10)
8.63
(284)
7.84 (259)
6.85 (226)
38 x 286
(2 x 12)
10.50 (345)
9.54 (313)
8.34 (274)
38 x 89
(2 x 4)
3.11
(103)
2.83 (93)
2.47 (81)
38 x 140
(2 x 6)
4.90
(161)
4.45 (147)
3.89 (129)
38 x 184
(2 x 8)
6.44
(211)
5.85 (192)
5.11 (169 )
38 x 235
(2 x 10)
8.22
(270)
7.47 (246)
6.52 (215)
38 x 286
(2 x 12)
10.00 (3210)
9.09 (2910)
7.94 (261)
38 x 89
(2 x 4)
2.81
(93)
2.55 (85)
2.23 (74 )
38 x 140
(2 x 6)
4.42
(146)
4.02 (132)
3.51 (116)
38 x 184
(2 x 8)
5.81
(191)
5.28 (174)
4.61 (152)
38 x 235
(2 x 10)
7.42
(244)
6.74 (222)
5.89 (194)
38 x 286
(2 x 12)
9.03
(298)
8.21 (2611)
7.17 (236)
303
APPENDIX A
Tables
Table 34
Maximum spans for ceiling joists attic not accessible by a stairway1, 2
Rafter Tied to Every Joist
Building Width up to
Building Width up to
8m
(26 ft., 3 in.)
9.8 m
(32 ft., 2 in.)
8m
(26 ft., 3 in.)
9.8 m
(32 ft., 2 in.)
Roof
Slope
Rafter
Spacing,
mm (in.)
1
(20)
or
less
1.5
(30)
2.0
(40)
or
more
1
(20)
or
less
1.5
(30)
2.0
(40)
or
more
1:3
400 (16)
600 (24)
400 (16)
600 (24)
400 (16)
600 (24)
400 (16)
1:2.4
1:2
1:1.71
1:1.33
1:1
1
(20)
or
less
1.5
(30)
2.0
(40)
or
more
1
(20)
or
less
1.5
(30)
2.0
(40)
or
more
11
11
10
11
10
11
600 (24)
11
400 (16)
600 (24)
400 (16)
600 (24)
Notes to Table 34
1. Nails not less than 79 mm (318 in.).
2. Ceiling joists must be fastened together with at least one more nail per joist splice than required for the
rafter-to-joist connection.
3. To determine the specified snow load in your location, contact your municipal building department.
304
APPENDIX A
Tables
Table 35
Minimum thickness of roof sheathing for sloping roofs1
Sheathing Thickness, mm (in.), for Truss or Rafter Spacing at
300 (12)
400 (16)
500 (20)
600 (24)
Supported2 edges
7.5 (516)
7.5 (516)
9.5 (38)
Unsupported edges
7.5 (516)
9.5 (38)
12.7 (12)
Supported edges
9.5 (38)
9.5 (38)
11.1 (716)
Unsupported edges
9.5 (38)
11.1 (716)
12.7 (12)
Panel mark
(performance-rated
panels)
Supported2 edges
1R16
1R20
1R24
Panel mark
(performance-rated
panels)
Unsupported edges
2R16
2R20
2R24
17 (1116)
17 (1116)
Lumber3
19 (34)
305
APPENDIX A
Tables
Table 36
Roofing types and slope limits for roofs
Slope
Type of Roofing
Minimum
Maximum
Built-up roofing
Asphalt base (graveled)
Asphalt base (without gravel)
Coal-tar base (graveled)
Cold process
1 in 50
1 in 25
1 in 50
1 in 25
1 in 4
1 in 2
1 in 25
1 in 1.33
Asphalt shingles
Normal Application
Low slope application
1 in 3
1 in 6
No limit
No limit
Roll roofing
Smooth and mineral surfaced
480 mm (19 in.) wide selvage asphalt roofing
Cold application felt
1 in 4
1 in 6
1 in 50
No limit
No limit
1 in 1.33
Wood shingles
1 in 4
No limit
Handsplit shakes
1 in 3
No limit
1 in 4
No limit
1 in 4
No limit
1 in 4
No limit
Slate shingles
1 in 2
No limit
Clay tile
1 in 2
No limit
1 in 4
No limit
Table 37
Exposure and thickness of wood shingles and machine-grooved shakes walls
Maximum Exposure, mm (in.)
Shake or Shingle
Length, mm (in.)
Single
Coursing
Double
Coursing
Minimum Butt
Thickness, mm (in.)
400 (16)
190 (712)
305 (12)
10 (38)
450 (18)
216 (812)
356 (14)
11 (716)
600 (24)
292 (1112)
406 (16)
13 (12)
306
APPENDIX A
Tables
Table 38
Stapling table, mm (in.)
A)
B)
C)
D)
E)
F)
G)
H)
I)
307
APPENDIX A
Tables
Table 39
Stucco mixes (by volume)
Portland Cement
Masonry Cement,
Type H
1
1
Lime
Aggregate
4 to 1
1
Table 40
Minimum thickness of flashing materials
Material
Wall Flashing
Cladding
Above-Grade Masonry
Exposed
Concealed
Aluminum
0.48 (0.019)
0.48 (0.019)
0.48 (0.019)
Copper
0.46 (0.018)
0.46 (0.018)
0.36 (0.014)
0.36 (0.014)
Copper or aluminum
laminated to felt or
kraft paper
0.05 (0.002)
Galvanized steel
0.33 (0.013)
0.33 (0.013)
0.33 (0.013)
0.33 (0.013)
Lead sheet
1.73 (0.068)
1.73 (0.068)
1.73 (0.068)
1.73 (0.068)
Polyethylene
0.50 (0.02)
Standard
Zinc
0.35 (0.014)
0.35 (0.014)
0.35 (0.014)
0.35 (0.014)
Vinyl
1.02 (0.04)
308
APPENDIX A
Tables
Table 41
Dimensions for wood-strip flooring
Minimum Thickness of Flooring, mm (in.)
Type of
Flooring
Maximum Joist
Spacing, mm (in.)
With Subfloor
No Subfloor
Matched hardwood
(interior use only)
400 (16)
600 (24)
7.9 (516)
7.9 (516)
19.0 (34)
33.3 (1516)
Matched softwood
(interior or exterior use)
400 (16)
600 (24)
19.0 (34)
19.0 (34)
19.0 (34)
31.7 (114)
400 (16)
600 (24)
25.4 (1)
38.1 (112)
Table 42
Nailing of wood-strip flooring
Finish Floor Thickness,
mm (in.)
Minimum Length of
Flooring Nails, mm (in.)
Maximum Spacing of
Flooring Nails, mm (in.)
7.9 (516)
38 (112)
200 (8)
11.1 (716)
51 (2)
300 (12)
19.0 (34)
57 (214)
400 (16)
25.4 (1)
63 (212)
400 (16)
31.7 (114)
70 (234)
600 (24)
38.1 (112)
83 (314)
600 (24)
Note to Table 42
1. Staples are permitted to be used to fasten wood strip flooring not more than 7.9 mm (516 in.) in thickness provided
the staples are not less than 29 mm (1316 in.) long with a shank diameter of 1.19 mm (0.047 in.) and a width of
4.7 mm (316 in.) crowns.
309
APPENDIX A
Tables
Table 43
Built-up beams for exterior decks (lumber not incised)
Number and Size of Plys mm (in.)
D.Fir-L
Hem-Fir
S-P-F
Northern
Species
Post
Spacing
m
2.4
2.7
3.0
3.3
3.7
4.3
ft.
10
11
12
14
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 184
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 8
1.8
1-38 x 184
1-38 x 184
1-38 x 235
1-38 x 235
1-38 x 235
2-38 x 184
1-2 x 8
1-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 8
2.4
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
2-38 x 235
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1.8
1-38 x 184
1-38 x 184
1-38 x 184
1-38 x 235
1-38 x 235
1-38 x 235
1-2 x 8
1-2 x 8
1-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
2.4
1-38 x 235
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
1-2 x 10
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1.8
1-38 x 184
1-38 x 184
1-38 x 184
1-38 x 235
1-38 x 235
1-38 x 235
1-2 x 8
1-2 x 8
1-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
2.4
1-38 x 235
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
1-2 x 10
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 184
1-38 x 184
1-38 x 184
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 8
1-2 x 8
1-2 x 8
1.8
1-38 x 235
1-38 x 235
1-38 x 235
2-38 x 184
2-38 x 184
2-38 x 184
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 8
2-2 x 8
2-2 x 8
2.4
2-38 x 184
2-38 x 235
2-38 x 235
2-38 x 235
2-38 x 235
2-38 x 286
2-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 12
Joist Span
Continued on p. 311
310
APPENDIX A
Tables
Table 43 (continued)
Built-up beams for exterior decks (lumber incised)1
Number and Size of Plys mm (in.)
D.Fir-L
Hem-Fir
S-P-F
Northern
Species
Post
Spacing
m
2.4
2.7
3.0
3.3
3.7
4.3
ft.
10
11
12
14
Joist Span
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 184
1-38 x 184
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 8
1-2 x 8
1.8
1-38 x 235
1-38 x 235
1-38 x 235
1-38 x 235
2-38 x 184
2-38 x 184
1-2 x 10
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 8
2-2 x 8
2.4
2-38 x 184
2-38 x 184
2-38 x 235
2-38 x 235
2-38 x 235
2-38 x 235
2-2 x 8
2-2 x 8
2-2 x 10
2-2 x 10
2-2 x 10
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 184
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 8
1.8
1-38 x 184
1-38 x 235
1-38 x 235
1-38 x 235
1-38 x 235
2-38 x 184
1-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 8
2.4
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
2-38 x 235
2-38 x 235
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
2-2 x 10
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 140
1-38 x 184
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 6
1-2 x 8
1.8
1-38 x 184
1-38 x 184
1-38 x 235
1-38 x 235
1-38 x 235
2-38 x 184
1-2 x 8
1-2 x 8
1-2 x 10
1-2 x 10
1-2 x 10
2-2 x 8
2.4
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
2-38 x 235
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
2-2 x 10
1.2
1-38 x 140
1-38 x 140
1-38 x 184
1-38 x 184
1-38 x 184
1-38 x 235
1-2 x 6
1-2 x 6
1-2 x 8
1-2 x 8
1-2 x 8
1-2 x 10
1.8
1-38 x 235
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 184
2-38 x 235
1-2 x 10
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 8
2-2 x 10
2.4
2-38 x 235
2-38 x 235
2-38 x 235
2-38 x 235
2-38 x 286
2-38 x 286
2-2 x 10
2-2 x 10
2-2 x 10
2-2 x 10
2-2 x 12
2-2 x 12
Notes to Table 43
1. Incising is knife cutting the surface of wood to help perservatives penetrate the wood.
2. Design based on 2001 CAN/CSA O86.
3. Live load = 40 psf (1.9 kPa), Dead load = 10 psf (0.5 kPa).
4. Lumber No. 2 and Better grade, pressure treated, wet service.
5. Beam selection is for a beam on the edge of a deck. Double the number of plys for middle beams supporting joists on
both sides.
6. Nail-laminate the beams to act as a single member (see Columns and Beams).
311
APPENDIX A
Tables
Table 44
Joists for exterior decks
Joist span, m (ft.in.)
Joists not incised
Northern Species
(includes any
Canadian species
covered by the
NLGA Standard
Grading Rules
Joists incised
Joist Size
mm
400
600
400
600
in.
16
24
16
24
38 x 140
2.9
2.3
2.6
2.2
2x6
9-6
7-6
8-6
7-2
38 x 184
3.5
2.8
3.2
2.6
2x8
11-6
9.2
10-6
8-6
38 x 235
4.3
3.5
3.9
3.2
2 x 10
14-1
11-6
12-9
10-6
38 x 140
2.9
2.5
2.8
2.3
2x6
9-6
8-2
9-2
7-6
38 x 184
3.7
3.0
3.4
2.7
2x8
12-1
9-9
11-2
8-10
38 x 235
4.3
3.6
4.1
3.4
2 x 10
14-1
11-9
13-4
11-2
38 x 140
2.8
2.4
2.7
2.3
2x6
9-2
7-10
8-10
7-6
38 x 184
3.7
3.1
3.5
2.8
2x8
12-1
10-2
11-6
9-2
38 x 235
4.3
3.8
4.3
3.5
2 x 10
14-1
12-6
14-1
11-6
38 x 140
2.5
2.0
2.3
1.9
2x6
8-2
6-7
7-6
6-2
38 x 184
3.0
2.5
2.8
2.3
2x8
9-9
8-2
9-2
7-6
38 x 235
3.7
3.0
3.4
2.8
2 x 10
12-1
9-9
11-2
9-2
Notes to Table 44
1. Incising is knife cutting the surface of wood to help perservatives penetrate the wood.
2. Design based on 2001 CAN / CSA O86
3. Live load + 1.9 kPa (40 psf), Dead load = 0.5 kPa (10 psf).
4. Lumber No. 2 and Better grade, pressure treated, wet service conditions.
312
APPENDIX B
313
APPENDIX B
Cutaway View of a Wood-frame House
76
77
68
32 50
5149
48
33
34
58
59
61
67
62
65
55
57
64
71
63
60
73
40
56
37
39
38
42
52
53
54
41
36
31
43
30
66
74
72
44
75
42
42
69
70 42
47
46
35
24
23
7
Foundation Excavation
1. Excavation to solid rock
or below the depth of
frost penetration
2. Concrete footing with key
3. Perforated perimeter
drain tile
4. Crushed stone with
soil filter cloth over
5. Galvanized steel basement
window well
6. Vertical drain to drain tile
7. Clean free-draining
backfill material
8. Slope ground for
surface drainage
4 3
11
12
10
18
13 6
14
1634
17
15
33
Basement Floor
19
22
21
20
45
28
27
26
25
29
Floor Platforms
and Headers
Continued on p. 315
314
APPENDIX B
Cutaway View of a Wood-frame House
(Continued)
Interior Finishes
Brick
Partition Walls
Roof Finishes
Ventilation and
Mechanical Equipment
315
17-12-13
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