Workbook: Wood Frame Construction Manual Wood Frame Construction Manual
Workbook: Wood Frame Construction Manual Wood Frame Construction Manual
Workbook: Wood Frame Construction Manual Wood Frame Construction Manual
E D I T I O N
WFCM
®
WOOD
WOOD FRAME
FRAMECONSTRUCTION
CONSTRUCTIONMANUAL
MANUAL
®
WORKBOOK
DESIGN OF WOOD FRAME BUILDINGS FOR
HIGH WIND, SNOW, AND SEISMIC LOADS
AMERICAN
WOOD
APPROVED
AUGUST 7, 2017 COUNCIL
2018 Wood Frame Construction Manual Workbook
2018 WFCM Workbook – Design of Wood Frame Buildings for High Wind, Snow, and Seismic Loads
ISBN 978-1-940383-50-7
Copyright Permission
American Wood Council
222 Catoctin Circle, SE, Suite 201
Leesburg, VA 20175
info@awc.org
FOREWORD
This Wood Frame Construction Manual stress design. See the AWC website (www.awc.org)
Workbook (WFCM Workbook) provides a design for an in-depth overview of the WFCM.
example and typical checklist related to design of a While building codes (and the WFCM) are
wood-frame structure in accordance with the organized based on the construction sequence
American Wood Council’s (AWC) Wood Frame (foundation to roof), this design example is
Construction Manual (WFCM) for One- and Two- organized based on the typical design sequence
Family Dwellings, 2018 Edition. The design (roof to foundation).
example uses plans from a 2-story residence Special effort has been made to assure that the
designed to resist high wind, seismic, and snow information presented in this document reflects the
loads. All three loading conditions are evaluated in state of the art. However, the American Wood
this example to show the broad range of the WFCM Council does not assume responsibility for
applicability. The authority having jurisdiction particular designs or calculations prepared from this
should be consulted for applicable load conditions. publication.
The design example is based primarily on AWC invites and welcomes comments,
prescriptive provisions found in Chapter 3 of the inquiries, and suggestions relative to the provisions
WFCM. References to tables and section numbers of this document.
are for those found in the 2018 WFCM, unless noted
otherwise. Additional engineering provisions or American Wood Council
alternate solutions are provided where necessary.
All loads and resistances are based on allowable
The design example is based in part on AWC’s Colonial Homes Idea House in Williamsburg, VA designed by nationally
acclaimed architect William E. Poole. The house was opened to the public in June 1995 and was featured in the October
1995 issue of Colonial Homes magazine.
The colonial style home featured both traditional and modern wood applications. The façade replicates an historic home in
Connecticut. Clad in southern pine siding, the house had glulam door headers, oak floors, and antiqued wood kitchen
cabinets. But what caught visitors’ attention most were the intricate wood moldings throughout the house and the inlaid
wood design bordering the foyer floor.
The following key explains the color code and nomenclature used throughout the WFCM Workbook.
Value Indicates “value” may be used for design – could include multiple options.
Value Bold font indicates “value” controls design.
OK Indicates “value” meets design criteria.
NG Indicates “value” does not meet design criteria.
Indicates significant change to 2018 WFCM Workbook vs. 2015 WFCM Workbook.
For ease of reference, Tables created in the WFCM Workbook are numbered to correspond with the respective section in
which they are located. All table numbers are preceded by a capital “W” (e.g. Table W4.4) to distinguish them from Tables
which are referenced in the WFCM (e.g. Table 3.15).
Table of Contents
Part Title Page
NOTES
GENERAL
INFORMATION
BUILDING DESCRIPTION
BUILDING DESCRIPTION
North
Lateral Loads:
Wind:
3-second gust wind speed in Exposure Category B (700 yr. return) = 160 mph
Seismic:
Seismic Design Category (SDC) – (ASCE 7-16 Section 11.6 and IRC Subcategory) = D1
Vertical force distribution factor (F) – (ASCE 7-16 Section 12.14.8.1) = 1.2
Gravity Loads*:
Roof: Floors:
Roof Dead Load = 10 psf First Floor Live Load = 40 psf
Ground Snow Load, Pg = 30 psf Second Floor Live Load = 30 psf
Roof Live Load = 20 psf Attic Floor Live Load = 30 psf
Floor Dead Load = 10 psf
Ceiling:
Roof Ceiling Load = 10 psf
Walls:
*Assumptions vary for wind and seismic dead loads Wall Dead Load = 11 psf
LOAD PATHS
WFCM 2.1.2 - A continuous load path shall be provided to transfer all lateral and vertical loads from the roof, wall, and floor
systems to the foundation.
WFCM 1.3 Definitions - Continuous Load Path: The interconnection of all framing elements of the lateral and vertical force
resisting systems, which transfers lateral and vertical forces to the foundation.
2018 WFCM Figure 2.2b for shear connection locations is shown here as an example. See 2018 WFCM Figures 2.2a and c for
typical lateral and uplift connections, respectively.
CHECKLIST
The following checklist is used to assist with the evaluation of a structure in accordance with WFCM Chapter 3 prescriptive
provisions. Items are keyed to sections of the WFCM Chapter 3 to allow a systematic evaluation of the structure. Blank
checklists are reproduced in the Appendix of the workbook.
Notes
FINISHED ATTIC
Roof Framing Plan (East Section) Ceiling Framing Plan (East Section)
Roof Framing Plan (West Section) Ceiling Framing Plan (West Section)
Rafter Span Adjustment - Thrust (Tables 3.26A-L Footnote 1): ................ 1.0 (Ctf)
Sloped Roof Adjustment (Tables 3.26A-C Footnote 2): ............................ 1.05 (Csr)
Pitch and deflection limit adjustment (Table 3.26M Footnote 1): .............. 1.09 (Cpd)
Table W4.1 Selection of Species, Grade, Size, and Spacing for Rafters: (Table 3.26B, E & M)
Species Douglas Fir-
Hem-Fir Southern Pine Spruce-Pine-Fir
Larch
Spacing 16" 16" 16" 16"
Grade #2 #2 #2 #2
Table 3.26B Span (Lt) 2x8 18'-5" 2x8 17'-3" 2x8 17'-1" 2x8 17'-9"
Trial
Live Load Span 18.4(1.0)(1.05) 17.3(1.0)(1.05) 17.1(1.0)(1.05) 17.75(1.0)(1.05)= and
LLL=Lt(Ctf)(Csr) = 19'-4" Ok = 18'-2" Ok = 18'-0" Ok 18'-6" Ok error
Table 3.26E Span (Lt) 2x10 18'-9" 2x10 18'-2" 2x10 16'-10" 2x10 18'-5"
Snow Load Span 18.75(1.0) = 18.2(1.0) = 16.8(1.0) = 18.4(1.0) = Trial
LSL=Lt(Ctf) 18'-9" Ok 18'-2" Ok 16'-10" Ok 18'-5" Ok and
error
Table 3.26M Span (Lt) 2x10 17'-3" 2x10 16'-2" 2x10 14'-10" 2x10 16'-8"
Wind Load Span 17.25(1.09) = 16.2(1.09) = 14.8(1.09) = 16.7(1.09) = Trial
LWL=Lt(Cpd) 18'-7" Ok 17'-7" Ok 16'-2" Ok 18'-2" Ok and
error
Notes: as an energy consideration, 2x12 rafters might be a minimum requirement for batt insulation.
* Alternatively, a Ridge Beam could be designed per Table 3.29. Additional columns at beam ends would
be required to establish load path to the foundation. Also, fasteners will need to be designed to resist
uplift from the rafters at each end of the ridge beam.
Ground Snow Load: ...................................................................... 30 psf
Live Load: ...................................................................................... 20 psf
Dead Load: ..................................................................................... 10 psf
Required Span: ............................................................................... 25' - 6"
Building Width: ............................................................................. 32' - 0" (interpolation req’d)
5-1/8" x 19-1/4" or 3-1/8" x 24-3/4" 20F-1.5E Glulam with Fvx=210psi OK
Table W4.2 Selection of Species, Grade, Size, and Spacing for Rafters with a Raised Ceiling:
(Table 3.26B, E & M)
Species Douglas Fir- Hem-Fir Southern Pine Spruce-Pine-Fir
Larch
Spacing 12" 12" 12" 12"
Grade No. 2 No. 2 No. 2 No. 2
Table 3.26B Span (Lt) 2x10 26'-0" 2x10 24'-3" 2x10 23'-5" 2x10 24'-10"
Trial
Live Load Span 26.0(0.67)(1.05) 24.3(0.67)(1.05) 23.4(0.67)(1.05)= 24.8(0.67)(1.05)= and
LLL=Lt(Ctf)(Csr) = 18'-3" Ok = 17'-1" Ok 16'-6" Ok 17'-6" Ok error
Table 3.26E or 2x10 2x12 2x10 2x12
24'-1" 24'-4" 24'-1" 24'-8"
Span Calc Span* (Lc) SS No. 2 DSS No. 2 Trial
and
Snow Load Span 24.1(0.67) = 24.3(0.67) = 24.1(0.67) = 24.67(0.67) = error
LSL=Lc(Ctf) 16'-2" Ok 16'-3" Ok 16'-1" Ok 16'-6" Ok
Table 3.26M Span (Lt) 2x8 14'-8" 2x10 18'-3" 2x10 18'-4" 2x10 18'-10"
Trial
Wind Load Span 14.7(1.09) 18.25(1.09) 18.3(1.09) 18.8(1.09) and
LWL=Lt(Cpd) =16'-0" Ok =19'-11" Ok =19'-11" Ok =20'-5" Ok error
*AWC Span Calculator used since tabulated values are not given in the WFCM for spans greater than 20 feet.
Some building codes require that ridge boards be of continuous length. Long lengths are possible with
engineered wood products, or one could be built up using two layers of 3/8" wood structural panel
material ripped to depth and end joints offset.
Table W4.3 Selection of Specie, Grade, Size, and Spacing for Floor Joists: (Table 3.18A)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 16" 16" 16" 16"
Grade #2 #2 #2 #2
Size 2x10 2x10 2x12 2x10
Maximum Span 17'-5" Ok 16'-10" Ok 18'-6" Ok 17'-2" Ok
Required Span (raised 1/3 vertical distance from the top plate): ................ 21.3 ft
Spacing (see rafter spacing in Table W4.2): ............................................... 12 in.
Required E and Fb at 12"o.c. joist spacing for 21.3' span from Table 2.12A:
Size 2x6 2x8
Required E 2,100,000 1,000,000 psi
Required Fb 1354 825 psi
Table W4.4 Select Grade and adjustment factors from NDS Table 4A and 4B based on required E
and Fb above:
Specie Douglas Fir- Hem-Fir Southern Pine Spruce-Pine-Fir
Larch
Size & Grade 2x8 No.2 2x8 No. 2 2x8 No. 2 2x8 No. 2
Tabulated E, psi 1,600,000 1,300,000 1,400,000 1,400,000 Trial
and
Tabulated Fb, psi 900 850 925 875 error
Size Factor, CF 1.2 1.2 1.0 1.2
Load Duration
1.0 1.0 1.0 1.0
Factor, CD
Repetitive Member
1.15 1.15 1.15 1.15
Factor, Cr
Allowable Fb, psi 900(1.2)(1.0)(1.15) 850(1.2)(1.0)(1.15) 925(1.0)(1.0)(1.15) 875(1.2)(1.0)(1.15)
= 1,242 psi Ok = 1,173 psi Ok = 1064 psi Ok = 1,208 psi Ok
WSP sheathing is required for the ceiling diaphragm since 15.9' required length of gypsum diaphragm
is greater than the 14.5' length of the raised ceiling.
Wall Framing
Non-Loadbearing (3-A and 2-A)
There are 2 options for designing gable end studs: 1) balloon framing from the second floor to the
rafters with a maximum stud length of 18.3 ft, or 2) stud length of 12.1 ft to the raised ceiling and
gable studs of 6.2 ft above with the raised ceiling diaphragm used for bracing.
9.3’
BLOCKING
REQUIRED
FOR SHEAR
9’
WALLS
Table W4.5 Selection of Species, Grade, Size, and Spacing for Non-loadbearing Studs
(Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 12" * 12" * 12" * 12" *
Grade No. 2 No. 2 No. 2 No. 2
Size 2x6 2x6 2x6 2x6
Maximum Length (Wind) 19'-5" OK 18'-0" NG** 18'-6" OK 18'-6" OK
Maximum Length (D+L) 20'-0" OK 20'-0" OK 20'-0" OK 20'-0" OK
* Stud spacing can be increased to 16" o.c. at a distance of roughly 4-5' on either
side of the ridge where stud heights drop to levels that allow greater spacing.
Stud spacing of 16" o.c. at the corners also works based on Table 3.20B1
Footnote “a” since allowable stud heights at 24" o.c. are greater than 11.3' at 4'
from the corners.
** Double studs at the ridge location.
6.2’
3.1’
BLOCKING
REQUIRED
FOR SHEAR 9’
WALLS
Option 2 solution is shown in Table W5.3. Choose Option 2 to keep stud grades at No.3/Stud for
consistency with other framing. No.3/Stud grade 2x6 can be used for framing above the ceiling
diaphragm level (3-A) based on calculations from Table W4.6.
9.3’
Table W4.6 Selection of Species, Grade, Size, and Spacing for Non-loadbearing Studs
(Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 24" * 24" * 24" * 24" *
Grade No. 3/Stud No. 3/Stud No. 3/Stud No. 3/Stud
Size 2x6 2x6 2x6 2x6
Maximum Length 11'-6" OK 11'-3" OK 10'-6" OK 11'-3" OK
(Wind)
Maximum Length (D+L) 20'-0" OK 20'-0" OK 20'-0" OK 20'-0" OK
* No need to decrease stud spacing to 16" o.c. per Tables 3.20B1 Footnote “a” in the end zones
since stud lengths approach zero. However, spacing could be decreased to 16" o.c. for
consistency with stud spacing below the gable framing. See Table W5.4.
Connections
Lateral Framing and Shear Connections (WFCM 3.2.1)
Roof Assembly to Wall Assembly (WFCM 3.2.1.2)
Choose Rafter/Ceiling Joist to Top Plate Lateral and Shear Connection from Table 3.4A
Three second gust wind speed (700 yr) and exposure category: ....................... 160 mph Exp. B
Rafter/Ceiling Joist Spacing .............................................................................. 12 & 16 in.
Wall Height (2-1 and 2-2): ................................................................................ 9 ft
Top plate-to-ridge height: .................................................................................. 9.3 ft
Tabulated no. of toenails in each rafter/ceiling joist to top plate connection: ... 3
Top plate-to-ridge height adjustment (Footnote 4): .......................................... 1.0
Required no. of toenails (tabulated x adjustments) ........................................... 3*
* See Table W4.9 below for alternative minimum capacities for proprietary connectors.
Three second gust wind speed (700 yr) and exposure category: ................ 160 mph Exp. B
Rafter/Ceiling Joist Spacing ....................................................................... 16 in.
Table W4.7 Top and Bottom Plate to Stud Lateral Connections for Non-loadbearing Walls
Building Wall Elevation 3-B 3-A
Wall Height 9.3' 6.2'
Required no. of 16d commons per stud to plate connection 2* 2*
* See Table W4.9 for alternative minimum capacities for proprietary connectors.
Connections (cont’d)
Uplift Connections (WFCM 3.2.2)
Roof Assembly to Wall Assembly (WFCM 3.2.2.1)
Table W4.8 Roof to Wall Uplift Strap Connection from Table A-3.4
Building Wall Elevation 2-2 2-1
Three second gust wind speed (700 yr) and exposure category 160 mph Exp. B
Framing Spacing 16 in.
W
i Roof Span 32 ft
n Minimum tabulated number of 8d Common Nails required in each
4
d end of 1-1/4" x 20 gage strap every rafter / stud
No Ceiling Assembly nail increase (Footnote 2) 0
Minimum required number of 8d Common Nails in each end of
4*
strap every rafter / stud = Tabulated number of nails + Increases
* See Table W4.9 for alternative minimum capacities for proprietary connectors.
Note that rafters over the vaulted ceiling are at 12" o.c. while the loadbearing studs supporting
those rafters are at 16" o.c. To ensure that load path is maintained, a twist strap similar to the one
shown below (WFCM Figure 3.2j) would be required with a capacity per Table W4.9 below.
Connections (cont’d)
Table W4.9 Alternative proprietary connectors every rafter/stud with the following minimum
capacities from Tables 3.4 and 3.4C. Design for 16" o.c. rafter spacing which will be conservative
for 12" o.c. rafter spacing for the vaulted ceiling.
Loadbearing Non-Loadbearing
Building Wall Elevation 2-2 2-1 3-B 3-A
Wall Height 9' 9' 9.3' 6.2'
Loadbearing Walls - Tabulated minimum uplift connection
486 lbs n/a
capacity (Table 3.4)
Interior framing adjustment (Table 3.4 Footnote 1) 1.0 n/a
Roof dead load reduction (Table 3.4 Footnote 3) 0 n/a
W Non-Loadbearing Walls - Tabulated minimum uplift
n/a 671 lbs
i connection capacity (Table 3.4C and figure below)
n Connector location (Table 3.4C, Footnote 1) n/a Outside wall face
d
40/20 (19/32"
WSP minimum (Table 3.4C, Footnotes 2-4) n/a
nominal)*
Required Minimum Uplift Capacity of proprietary connector
486 lbs 537 lbs*
= Tabulated minimum capacity with Adjustments
Required Minimum Lateral Capacity – rafter/truss to wall
224 lbs n/a
(Table 3.4)
Tabulated Lateral Capacity – top and bottom plate to stud
n/a 159 plf** 141 plf
(Table 3.5)
Spacing multiplier (Table 3.5 Footnote 2) n/a 1.33 1.33
Required Minimum Lateral Capacity = tabulated capacity x
n/a 211 lbs 188 lbs
Adjustments
Tabulated Minimum Shear Parallel to Ridge Capacity
94 lbs n/a
(R=W/L=0.8) (Table 3.4)
Tabulated Minimum Shear Perpendicular to Ridge Capacity
n/a 148 lbs
(R=L/W=1.25)
Shear connection adjustment (Table 3.4 Footnote 4) 0.92 0.92
Required Minimum Shear Capacity 87 lbs 136 lbs
* To use 7/16" roof sheathing thickness, reduce outlooker overhang span to 19.2". Uplift = 537 lbs.
** For 3-B, maximum load based on stud length at the ridge. Loads will decrease as stud length decreases.
Connections (cont’d)
Sheathing and Cladding Attachment (WFCM 3.2.5)
Roof Sheathing (WFCM 3.2.4.1)
Three second gust wind speed (700 yr) and exposure category: ................ 160 mph Exp. B
Rafter/Truss Spacing:.................................................................................. 16 in.
Sheathing Type: .......................................................................................... 7/16" WSP G=0.5
Connections (cont’d)
Rather than using collar ties to resist upward ridge separation, choose
Ridge Tension Strap Connections from Table A-3.6)
Three second gust wind speed (700 yr) and exposure category: ................ 160 mph Exp. B
* Alternatively, use proprietary connectors with the following minimum capacity from Table 3.6
Tabulated minimum connection capacity: .................................................. 351
Ridge Strap Spacing Adjustment (Footnote 3):
Vaulted @ 12 in. o.c. ........................................................ 1.0
Attic @ 16 in. o.c. ............................................................. 1.33
Required minimum capacity of proprietary connector:
Tabulated minimum capacity x Applicable adjustment factors:
Vaulted @ 12 in. o.c. ........................................................ 351
Attic @ 16 in. o.c. ............................................................. 467
Connections (cont’d)
Table 3.1 Nailing Schedule
Choose Ceiling Joist to Parallel Rafter and Ceiling Joist (attic) Lap Connection from Table 3.9A
Tabulated number of 16d Common Nails required per heel joint splice: .. 5
Ceiling Height/Roof Ridge Height Adjustment (Footnote 5): ....... 1.0
*Alternatively, use proprietary connectors with the following minimum capacity from Table 3.9
Connections (cont’d)
Choose Ceiling Joist to Parallel Rafter and Raised Ceiling Joist Lap Connection from Table 3.9A
Tabulated number of 16d Common Nails required per heel joint splice: .. 4
Ceiling Height/Roof Ridge Height Adjustment (Footnote 5): ....... 1.5
*Alternatively, use proprietary connectors with the following minimum capacity from Table 3.9
Blocking to Rafter Connection from Table 3.1 ......... 2-8d common nails toe-nailed at each end
OR
Rim Board to Rafter Connection from Table 3.1: 2-16d common nails end-nailed at each end
Table W4.12 Gable Wall and Roof Framing and Connection Summary
Wall 2-2 2-1 3-B 3-A
No. 3/Stud No. 3/Stud
Stud Grade and Size
2x6 2x6
Stud Length 9.3' 6.2'
Stud Spacing 16" 16"
Roof to Wall Lateral/Shear 3-8d comm. 3-8d comm. 211 lbs 188 lbs
Roof to Wall Uplift 4-8d comm. 4-8d comm. 537 lbs* 537 lbs*
Plate to Stud Lateral 2-16d comm. 2-16d comm. 2-16d comm. 2-16d comm.
* 19/32" WSP sheathing and 24" outlooker requires 671 lbs uplift connector.
NOTES
Wall Framing
Wall Studs (WFCM 3.4.1.1)
Loadbearing (2-1 and 2-2)
Three second gust wind speed (700 yr) and Exposure category: ............... 160 mph Exp. B
Exterior Studs (ext. wood siding and int. gypsum bd.) Deflection: ............ H/180 in.
Wall Height: ............................................................................................... 9 ft
Studs supporting (Roof, Ceiling, Floors): .................................................. R+C+1F
Sheathing Type (3/8" wood structural panel or minimum sheathing): ....... WSP
To show that this is an iterative approach and that other factors may drive selection of stud size, the first
attempt will use 2x4 stud grade material. Start with Table 3.20B1 because shear walls will require WSP
sheathing.
Table W5.1 Selection of Species, Grade, Size, and Spacing for Loadbearing Studs
(Developed from WFCM Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 16" 16" 16" 16"
Grade No. 3/Stud No. 3/Stud No. 3 or Stud No. 3/Stud
Size 2x4 2x4 2x4 2x4
Maximum Length (Wind) 2
10-1" 9'-10" 9'-1" 9'-10"
Maximum Length (Dead 10'-0" 10'-0" 10'-0" 10'-0"
and Live Loads) 1
1. Studs support roof, ceiling, and attic floor, therefore from Table 3.20C spacing is 16" o.c.
The remainder of wall which supports only roof and ceiling could increase spacing to 24"
o.c., however due to standard construction practice, the spacing remains at 16" o.c.
2. Footnote “a” requires the stud spacing to be multiplied by 0.80 for framing within 4 ft of the
corners to address additional end zone loading requirements. Options:
a. Space studs at 12" o.c. within 4 ft of the corners.
b. Design for minimum sheathing materials per Table 3.20A1 and apply Footnote “a”.
c. Design for a higher grade or 2x6 studs at 24" o.c. and then space them at 16" o.c.
Since wall W2-A will require 2x6 studs, choose Option (c). Calculations per Table W5.2.
Table W5.2 Selection of Species, Grade, Size, and Spacing for Loadbearing Studs
(Developed from WFCM Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 24" * 24" * 24" * 24" *
Grade No. 3/Stud No. 3/Stud No. 3 or Stud No. 3/Stud
Size 2x6 2x6 2x6 2x6
Maximum Length (Wind) 1
11'-6" OK 11'-3" OK 10'-6" OK 11'-3" OK
Maximum Length (Dead 10'-0" OK 10'-0" OK 10'-0" OK 10'-0" OK
and Live Loads)
* Decrease all stud spacing to 16" o.c. to satisfy Table 3.20B Footnote “a” criteria.
AMERICAN WOOD COUNCIL
2018 Wood Frame Construction Manual Workbook 35
Wall studs are balloon-framed up to the raised ceiling to avoid creating a hinge in Wall 2-A,
which would occur if 9' studs were used.
CEILING
3.1’
BLOCKING WIND
9’
FLOOR
Three second gust wind speed (700 yr) and Exposure category: ............... 160 mph Exp. B
Exterior Studs (ext. wood siding and int. gypsum bd.) Deflection: ............ H/180 in.
Wall Height: ................................................................................................ 12.1 (max) ft
Sheathing Type (wood structural panel or minimum sheathing): .............. WSP
Selection of Specie, Grade, Size, and Spacing for wind and gravity loads: (Table 3.20B1 and
Table 3.20C).
Table W5.3 Selection of Species, Grade, Size, and Spacing for Non-loadbearing Studs
(Developed from WFCM Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Three second gust wind speed (700 yr) and Exposure category: ............... 160 mph Exp. B
Exterior Studs (ext. wood siding and int. gypsum bd.) Deflection: ............ H/180 in.
Wall Height: ................................................................................................ 9 ft
Sheathing Type (wood structural panel or minimum sheathing): .............. WSP
Selection of Specie, Grade, Size, and Spacing for wind and gravity loads: (Table 3.20B1 and
Table 3.20C). Plan for the 0.8 end zone stud spacing adjustment factor specified by footnote “a”
by starting with a 24" stud spacing. Even though 2x4 studs might work, start with 2x6 studs based
on all other walls being framed with 2x6.
Table W5.4 Selection of Species, Grade, Size, and Spacing for Non-loadbearing Studs
(Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Choose Building End Wall Double Top Plate Lap Splice Length from Table 3.21
Tabulated number of nails per each side of splice ...................................... 13-16d nails
Minimum Splice Length (2-16d nails per 6") (14 nails/4 nails/ft):............. 3.5 ft
Choose Building Side Wall Double Top Plate Lap Splice Length from Table 3.21
Tabulated number of nails per each side of splice ...................................... 16-16d nails
Minimum Splice Length (2-16d nails per 6")(16 nails/4 nails/ft):.............. 4.0 ft
* Full height studs could be determined based on 24" o.c. spacing from Tables W5.2-W5.4.
** WFCM 3.4.1.4.3 allows jack studs to be replaced with an equivalent number of full
height (king) studs if adequate gravity connections are provided.
AMERICAN WOOD COUNCIL
38 Second Story Design
Selection of Window Sill Plate Specie, Grade, and Size: ............. #2 1-2x6 (flat)
Tabulated Window Sill Plate Span: ............................................................ 6'-11"
Adjustment for framing not within 8' of corners (Footnote 1):................... 1.0
Wall Height Adjustment (Footnote 2: (H/10)1/2): ....................................... 0.95
Adjusted Maximum Sill Plate Length:
Tabulated max. Sill Plate Length wall Height Adjustment: ....... 7'-3" >6' OK
Number of full height (king) studs determined previously.
Wall Sheathing
Sheathing and Cladding (WFCM 3.4.4.1)
Choose Exterior Wall Sheathing OR Cladding from Tables 3.13A and 3.13B, respectively
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Sheathing Type (wood structural panels, fiberboard, board, hardboard): ... WSP
Strength Axis to Support (Parallel or Perpendicular): ................................ Parallel
Stud Spacing: .............................................................................................. 16 in.
Minimum Panel Thickness to resist suction loads: ..................................... 15/32 in.
LFH = 24 ft
LFH = 22 ft
LFH = 32 ft
LFH = 29 ft
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Maximum shear wall aspect ratio for wind (Table 3.17D Footnote 4): ...... 3.5:1
Minimum shear wall segment length (Wall height/aspect ratio) (9 ft/3.5): 2.6 ft
Minimum WSP sheathing thickness (per WFCM 3.4.4.2): ........................ 3/8 in.
NOTE: Minimum WSP thickness for suction controls
Minimum gypsum thickness (per WFCM 3.4.4.2): .................................... 1/2 in.
NOTE: Aspect ratio limit of 1.5:1 unblocked: 2:1 blocked
Maximum stud spacing (per WFCM 3.4.4.2): ........................................... 16 in.
8d common nails
@ 6” OC on
panel perimeter 5d cooler nails
@ 7” OC on
panel perimeter
8d common
nails @ 12” OC
in field 5d cooler nails
@ 10” OC in
field
3/8” wood
structural panel 1/2” gypsum
continuous wallboard on
height over wall interior
plates
Table W5.6 Calculation of Exterior Perforated Shear Wall Lengths and Nailing Requirements
Building Wall Elevation 2-2 2-1 2-B 2-A
Wall Height 9' 9' 9' 9'
Max. Unrestrained Opening Height 6'-0" 4'-6" 0 4'-6"
Max. Unrestrained Opening Heights as functions of wall height 2H/3 H/2 0 H/2
Actual Length of Full Height Sheathing (LFH) 24' 22' 32' 29'
Effective Length of Full Height Sheathing (LFH-Eff) 20'* 18'* 32' 29'
S Length of Wall (LWall) 40' 40' 32' 32'
e Min. Length Full Ht. Sheathing - Segmented Seismic (LSSW-S) 11.5' 11.5' 11.5' 11.5'
i
Percent Full Height Sheathing (LSSW-S / LWall) 29% 29% 36% 36%
s
m Perforated Length Increase Factor from Table 3.17E (CL) 1.55 1.31 1.00 1.27
i Min. Length Full Ht. Sheathing - Perforated Seismic 17.8' 15.1' 11.5' 14.6'
c LPSW-S = LSSW-S (CL)
LPSW-S < LFH-Eff Ok Ok Ok Ok
Actual Length of Full Height Sheathing (LFH) 24' 22' 32' 29'
Length of Wall (LWall) 40' 40' 32' 32'
W Min. Length Full Height Sheathing - Segmented Wind (LSSW-W) 9.5' 9.5' 11.8' 11.8'
i Percent Full Height Sheathing (LSSW-W / LWall) 24% 24% 37% 37%
n Perforated Length Increase Factor from Table 3.17E (C ) 1.62 1.34 1.00 1.27
L
d
Min. Length Full Ht. Sheathing - Perforated Wind
15.4' 12.7' 11.8' 15.0'
LPSW-W = LSSW-W (CL)
LPSW-W < LFH-Eff Ok Ok Ok Ok
* Includes a 2b/h reduction for exceeding 2:1 aspect ratio. See Table W5.5 footnote for explanation.
Table W5.7 Top Story Shear Wall Edge Nail Spacing and Wall Length Summary
Building Elevation 2-2 2-1 2-B 2-A
Segmented 6" 11.5' 6" 11.5' 6" 11.5' 6" 11.5'
Seismic
Perforated 6" 17.8' 6" 15.1' 6" 11.5' 6" 14.6'
Segmented 6" 9.5' 6" 9.5' 6" 11.8' 6" 11.8'
Wind
Perforated 6" 15.4' 6" 12.7' 6" 11.8' 6" 15.0'
See shear wall detailing summary tables at the end of this section for a final
comparison of wind vs. seismic results.
Floor Framing
Floor Joists (WFCM 3.3.1.1)
Choose Floor Joists from Tables 3.18A-B
Table W5.8 Selection of Specie, Grade, Size, and Spacing for Floor Joists (Table 3.18A)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Blocking per
WFCM 3.3.5
Floor opening
complies with
WFCM 3.1.3.2.g
(lesser of 12 ft or
50% of the
building
dimension).
Floor Framing
Floor Sheathing
Sheathing Spans (WFCM 3.3.4.1)
Choose Floor Sheathing from Table 3.14
Connections
Lateral Framing and Shear Connections (WFCM 3.2.1)
Wall Assembly (WFCM 3.2.1.3)
Top Plate to Top Plate
Table 3.1 for 6" WSP wall edge nail spacing ....................................... 2-16d Commons per foot
Top Plate Intersection (Table 3.1): .................................................... 4-16d Commons each joint side
Top or Bottom Plate to Stud (Table 3.1 & 3.5A): ............................. 2-16d Commons per stud*
* See header design for any additional nailing required for king studs. Also note that W2-A has a
12.1 foot wall height, however, 2-16d commons are sufficient.
Bridging to Floor Joist (Table 3.1): ...................................................... 2-8d Commons each end
Blocking to Floor Joist (Table 3.1): ...................................................... 2-8d Commons each end
Band Joist to Floor Joist (Table 3.1): ................................................... 3-16d Commons per joist
Floor Joist to Top Plate (Table 3.1): ..................................................... 4-8d Commons per joist
Blocking to Sill or Top Plate (Table 3.1): ............................................. 3-16d Commons each block
Connections (cont’d)
Uplift Connections (WFCM 3.2.2)
Table W5.9 Wall to Wall Uplift Strap Connection from Table A-3.4
Building Wall Elevation 2-1 2-2
Three second gust wind speed (700 yr) and Exposure category: 160 mph Exp. B
Framing Spacing 16 in.
W
i Roof Span 32 ft
n Minimum tabulated number of 8d Common Nails required in each 4
d end of 1-1/4" x 20 gage strap every stud
No Ceiling Assembly nail increase Table A-3.4 Footnote 2 0
Minimum required number of 8d Common Nails in each end of strap
4*
every stud = Tabulated number of nails - Reductions + Increases
*Non-loadbearing wall assemblies (2-A and 2-B) in accordance with Table W5.10 below (3.2.6.3)
Table W5.10 Alternative proprietary connectors every stud with the following minimum capacities
Building Wall Elevation 2-1 2-2 2-A 2-B
Loadbearing Walls - Tabulated minimum uplift connection capacity
486 lbs n/a
(Table 3.4)
Interior framing adjustment (The 75% uplift factor reduction allowed
1.0 n/a
by Table 3.4 Footnote 1 was not applied)
W
Roof dead load reduction (Table 3.4 Footnote 2) = 0 since the attic
i -0 lbs n/a
floor does not cover the entire second floor
n
Wall-to-Wall and Wall-to-Foundation reduction
d -97 lbs -97 lbs
(Table 3.4 Footnote 3) = [73 plf x (16" / 12"/ ft ) = 97 lbs]
Non-Loadbearing Walls - Tabulated minimum uplift connection
n/a 671 lbs
capacity (Table 3.4C)
Connector location (Table 3.4C, Footnote 1) n/a n/a
40/20 (19/32"
WSP minimum (Table 3.4C, Footnotes 2-4) n/a
nominal)*
Required minimum capacity of proprietary connector
389 lbs 440 lbs*
= Tabulated minimum capacity with Adjustments
Required number of 8d common nails (Z' = 104 lbs) in each end of
4 5 or 6**
straps on every stud = Required capacity ÷ Z'
* To use 7/16" roof sheathing thickness, reduce outlooker overhang span to 19.2". Tabulated uplift = 537 lbs. Wall
dead load can be deducted from uplift: 537-97=440 or 671-97=574.
** Five nails to resist 440 lbs uplift and 6 nails to resist 574 lbs uplift.
The assumption is that wall plate nailing to floor framing (WFCM 3.2.1.6 and Table 3.1) in addition to the
wind uplift straps (determined above), are sufficient to resist uplift requirements on the plate using the
Perforated Shear Wall Method. See 2015 SDPWS section 4.3.6.4.2.1.
Connections (cont’d)
Uplift Connections (WFCM 3.2.3)
Table W5.11 Alternative to metal straps on every stud - wood structural panels to resist wall plate
to wall stud uplift and shear from Table 3.4B
Building Wall Elevation 2-1 2-2 2-A 2-B
Three second gust wind speed (700 yr) and Exposure category 160 mph Exp. B 160 mph Exp. B
Roof Span 32 ft n/a *
W
i Shear Wall Sheathing Thickness (see shear wall design above) 15/32 in. 15/32 in.
n 8d common @ 8d common @
Shear Wall Nailing: size and spacing (panel edges and field)
d 6"/12" 6"/12"
Number of Rows Required at top and bottom of panel edges 2 2
Top and Bottom Panel Edge Nail spacing (WFCM Figure 3.2f) 4" ** 3" **
* An engineered approach using 2015 SDPWS to design gable end wall (2-A & 2-B) WSPs to resist
combined uplift and shear is as follows:
1. Uplift calculated in Table W5.10 for outlooker with 19.2" overhang gives 440 lbs and 24"
overhang gives 574 lbs.
2. Use SDPWS Table 4.4.1 to determine the appropriate ASD uplift capacity for the specified shear
wall nailing of 8d common 6" panel edge spacing, 12" field spacing as follows:
• For 2 rows of nails at top and bottom of panel edges spaced at 4":
o ASD Uplift Capacity = 432 lbs (864 lbs/2) < 440 lbs (19.2" outlooker overhang span) NG
• For 2 rows of nails at top and bottom of panel edges spaced at 3":
o ASD Uplift Capacity = 648 lbs (1,296 lbs/2) > 574 lbs (24" outlooker overhang span) OK
• Therefore 2 rows of 8d common nails spaced at 3" at top and bottom panel edges can be used
for both a 19.2" or a 24" outlooker overhang span.
See Figure 3.2f (shown below and right) for appropriate panel edge
nail spacing (3.2.3.5).
**WFCM 3.2.3.7a requires that nail spacing not be less than 6"
o.c. for a double row of fasteners to avoid tension perpendicular
to grain stresses in common framing members such as band
joists. An alternative to splicing panels at the band joist is to
splice panels at mid-stud height. Detailing shall be in accordance
with WFCM 3.2.3.7b.
AMERICAN WOOD COUNCIL
2018 Wood Frame Construction Manual Workbook 47
Connections (cont’d)
Overturning Resistance (WFCM 3.2.4)
Table W5.12 Calculate Hold-downs from Table 3.17F for Segmented and Perforated Shear Walls
Building Wall Elevation 2-1 2-2 2-A 2-B
Wall Height 9' 9' 9' 9'
S WSP Perimeter Edge Nail Spacing - seismic 6" 6" 6" 6"
e Tabulated hold-down connection capacity required –
i 2151 lbs 2151 lbs 2151 lbs 2151 lbs
seismic (Ts)
s
m Hold-down adjustment per Table 3.17F footnotes
1.0 1.0 1.0 1.0
i (Table 3.17D) (Csw)
c
Adjusted hold-down capacity (Tas = (Ts) / (Csw)) 2151 lbs 2151 lbs 2151 lbs 2151 lbs
WSP Perimeter Edge Nail Spacing - wind 6" 6" 6" 6"
W Tabulated hold-down connection capacity required –
i wind (Tw) 3924 lbs 3924 lbs 3924 lbs 3924 lbs
n
Hold-down adjustment per Table 3.17F Footnotes
d 1.0 1.0 1.0 1.0
(Table 3.17D) (Csw)
Adjusted hold-down capacity (Twa = (Tw) / (Csw)) – wind 3924 lbs 3924 lbs 3924 lbs 3924 lbs
Connections (cont’d)
Sheathing and Cladding Attachment – Resisting Suction Loads (WFCM 3.2.5)
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Stud Spacing: .............................................................................................. 16 in.
Sheathing Type (wood structural panels, board or lap siding): .................. WSP
Wall sheathing nailing requirement for shear walls (8d common nails required) control.
Foyer Window
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Roof Span: .................................................................................................. 32 ft
Header Span (Foyer Window): ................................................................... 6 ft
Typical Bedroom (3' header) Tabulated Uplift Capacity (interpolated): .... 545 lbs
Typical Bedroom (3' header) Tabulated Lateral Capacity (interpolated): .. 252 lbs
Connections (cont’d)
Choose Window Sill Plate Connections based on loads from Table 3.8
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Window Sill Plate Span: ............................................................................. 6 ft
Tabulated Lateral Connection Capacity at Each End of Window Sill Plate: ........... 504 lbs
FIRST STORY
DESIGN
Wall Framing
Wall Studs (WFCM 3.4.1.1)
Loadbearing (1-1 and 1-2)
Based on second floor wall designs, start with 2x6 studs @ 24" o.c.
Table W6.1 Selection of Species, Grade, Size, and Spacing for Loadbearing Studs
(Developed from WFCM Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 24" * 24" * 24" * 24" *
Grade No. 3/Stud No. 3/Stud No. 3 or Stud No. 3/Stud
Size 2x6 2x6 2x6 2x6
Maximum Length (Wind) 1 11'-6" OK 11'-3" OK 10'-6" OK 11'-3" OK
Maximum Length (Dead 10'-0" OK 10'-0" OK 10'-0" OK 10'-0" OK
and Live Loads)
* Decrease all stud spacing to 16" o.c. to satisfy Table 3.20B Footnote “a” criteria.
Plan for Footnote “a” stud spacing adjustment factor of 0.8 by starting with 24" stud spacing.
Even though 2x4 studs might work, start with 2x6 studs based on all other walls being framed
with 2x6.
Table W6.2 Selection of Species, Grade, Size, and Spacing for Non-loadbearing Studs
(Developed from WFCM Tables 3.20B1 and 3.20C)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 24" * 24" * 24" * 24" *
Grade No.3/Stud No.3/Stud No. 3 or Stud No.3/Stud
Size 2x6 2x6 2x6 2x6
Maximum Length (Wind) 11'-6" OK 11'-3" OK 10'-6" OK 11'-3" OK
Maximum Length (Dead
20'-0" OK 20'-0" OK 20'-0" OK 20'-0" OK
and Live Loads)
* Decrease all stud spacing to 16" o.c. per Table 3.20B Footnote “a”.
Tabulated number of nails per each side of splice: ..................................... 13-16d nails
Minimum Splice Length (2-16d nails per 6") (13 nails/4 nails/ft): ............ 3.5 ft
Choose Building Side Wall Double Top Plate Lap Splice Length from Table 3.21
Tabulated number of nails per each side of splice: .................................... 16-16d nails
Minimum Splice Length (2-16d nails per 6") (16 nails/4 nails/ft): ............ 4.0 ft
Typical Window headers (3' required): ............... Dropped 2-2x8's 3'-8" >3' OK
Typical Window headers (3' required): ................... Raised 2-2x6's 3'-0" >3' OK
Number of Jack Studs Required: ................................................... 2**
Number of Full Height (King) Studs Required:............................. 1
* Full height studs could be determined based on 24" o.c. spacing from Tables W6.1-W6.2.
** WFCM 3.4.1.4.3 allows jack studs to be replaced with an equivalent number of full
height (king) studs if adequate gravity connections are provided.
If all first floor headers align vertically with second floor headers, only one floor is being carried and
headers could be designed for more efficiency (Table 3.24A1/A2 adjusted by 1.4 for half the tributary
area). However, jack studs still need to be designed for roof, ceiling, and two floors.
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Required Span: ............................................................................................ 3 and 4 ft
Selection of Window Sill Plate Grade, and Size: ...................................... 1-2x6 (flat)
Tabulated Window Sill Plate Span: ............................................................ 7'-3"
Wall Height Adjustment (Footnote 3: (H/10)1/2): ....................................... 0.95
Table 3.23C
Number of Full Height (King) Studs Required:.......................................... 2
Reduced Full Height Stud Requirements (Table 3.23D) x/h = 0.25: .......... 2
Wall Sheathing
Sheathing and Cladding (WFCM 3.4.4.1)
Choose Exterior Wall Sheathing OR Cladding from Tables 3.13A and 3.13B respectively
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
LFH = 25 ft
LFH = 22 ft
LFH = 25 ft
LFH = 29 ft
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Maximum shear wall aspect ratio for wind (Table 3.17D Footnote 4): ...... 3.5:1
Minimum shear wall segment length (Wall height/aspect ratio) (9 ft/3.5): 2.6 ft
8d common nails
@ 6” OC on
panel perimeter 5d cooler nails
@ 7” OC on
panel perimeter
8d common
nails @ 12” OC
in field 5d cooler nails
@ 10” OC in
field
3/8” wood
structural panel 1/2” gypsum
continuous wallboard on
height over wall interior
plates
Table W6.4 Calculation of Exterior Perforated Shear Wall Lengths and Nailing Requirements
Building Wall Elevation 1-2 1-1 1-B 1-A
Wall Height 9' 9' 9' 9'
Max. Unrestrained Opening Height 7'-6" 7'-6" 4'-6" 7'-6"
Actual Length of Full Height Sheathing (LFH) 25' 22' 25' 29'
Effective Length of Full Height Sheathing for Seismic (LFH-Eff) 22'* 18'* 25' 29'
S Length of Wall (LWall) 40' 40' 32' 32'
e Min. Length Full Ht. Sheathing - Segmented Seismic (LSSW-S) 20.0' 13.6' 20.0' 20.0'
i Percent Full Height Sheathing (L
SSW-S / LWall) 50% 34% 63% 63%
s
m Perforated Length Increase Factor from Table 3.17E (CL) 1.43 1.66 1.14 1.29
i Min. Length Full Ht. Sheathing - Perforated Seismic 28.6' 22.6' 22.8' 25.8'
c LPSW-S = LSSW-S (CL)
LPSW-S < LFH-Eff NG** NG** OK OK
Length of Wall (LWall) 40' 40' 32' 32'
W Min. Length Full Height Sheathing - Segmented Wind (LSSW-W) 18.8' 13.9' 17.4' 23.6'
i Percent Full Height Sheathing (LSSW-W / LWall) 47% 35% 54% 74%
n Perforated Length Increase Factor from Table 3.17E (CL) 1.47 1.64 1.18 1.19
d Min. Length Full Ht. Sheathing - Perforated Wind
27.6' 22.8' 20.5' 28.1'
(LPSW-W = LSSW-W (CL))
LPSW-W < LFH-Eff NG** NG** OK OK
* Includes a 2bs/h adjustment for exceeding 2:1 aspect ratio for seismic. See Table W5.5 for
explanation.
** See Table W6.5 and W6.6 for modifications to nailing patterns and sheathing lengths to allow the
perforated shear wall method to work.
Table W6.5 Calculation of Modified Edge Nailing and Sheathing Length Requirements for Seismic
Design of Perforated Shear Walls 1-1 and 1-2.
Modified Shear Wall Calculations from Tables W6.3 and W6.4 1-2 1-1
Wall Height 9' 9'
Max. Unrestrained Opening Height 7'-6" 7'-6"
Max. Unrestrained Opening Heights as functions of wall height 5H/6 5H/6
Length of Full Height Sheathing (LFH) 25' 22'
Effective Length of Full Height Sheathing for Seismic (LFH-Eff) 22'* 18'*
Tabulated Minimum Length Full Height Sheathing for Seismic Loads per
18.1' 18.1'
Table 3.17C1 (Ls) L/W = 1.25 (interpolated)
Vertical distribution factor adjustment per Table 3.17C Footnote 2 (Cvd) 0.92 0.92
WSP Perimeter Edge Nail Spacing – Seismic
(WFCM 3.4.4.2b + 3.4.4.2.1) Note: nail spacing for elevations 1-2 and 1-1 3" 3"
reduced to provide increased unit shear capacity for seismic.
Sheathing Type Adjustment per Table 3.17D (Csw) 0.53 0.53
Adjustment for other dead load case (Cdl) per Table 3.17C Footnote 4 1.2 1.2
Min. Length Full Ht. Sheathing – Segmented Seismic
10.6' 10.6'
LSSW-S = Ls (Cvd) (Csw) (Cdl)
Length of Wall (LWall) 40' 40'
Min. Length Full Ht. Sheathing – Segmented Seismic (LSSW-S) 10.6' 10.6'
Percent Full Height Sheathing (LSSW-S / LWall) 40% 40%
Perforated Length Increase Factor from Table 3.17E (CL) 1.56 1.56
Min. Length Full Ht. Sheathing - Perforated Seismic
16.5' 16.5'
LPSW-S = LSSW-S (CL)
LPSW-S < LFH-Eff OK OK
* Includes a 2bs/h adjustment for exceeding 2:1 aspect ratio for seismic. See Table W5.5 for explanation.
Since wall 1-1 does not have enough capacity for wind using the Perforated Shear Wall (PSW) method, it
will be designed per 2015 Special Design Provisions for Wind and Seismic (SDPWS) and 2018 WFCM
Chapter 2 Engineered Design provisions. Another option is to use WFCM Table 3.17D adjustments to
design a 2-sided WSP shear wall.
To calculate the wind shear load on wall 1-1, use WFCM Table 2.5B to determine unit lateral loads for
the roof and floor diaphragms. Roof diaphragm load = 169 plf (interpolated) and floor diaphragm load =
194 plf. The floor diaphragm load can be modified by Table 2.5B footnote 2 for a 9' wall height = 0.91.
Per Table 2.5B Footnote 3, Table 2.1.3.1 can be used to reduce the MWFRS load by 0.97 based on a
mean roof height less than 33'. Per Table 2.5B footnote 5, the shear load on wall 1-1 = 32' [194(0.91) +
169](0.97)/2 = 5,370 lbs. Modified results are as follows:
Table W6.7 Calculation of Sheathing Length Requirements for Wind Design of Wall 1-1 using the
Perforated Shear Wall Method from 2015 SDPWS Section 4.3.3.5.
Modified Perforated Shear Wall Calculations from Table W6.6 1-1
Wall Height 9'
Total length of wall (LWall) 40'
Total area of openings (Ao = 6(7.5)+4(3)(4.5)) (ft2) 99
Aspect ratio adjustment per SDPWS 4.3.4.3 (2bs/h) 0.67
Length of full-height sheathing (Li): 2(5') + 4(0.67)(3') = 18 ft 18'
Sheathing area ratio (r) per SDPWS Equation 4.3-6 0.62
Shear capacity adjustment factor (Co) per SDPWS Equation 4.3-5 0.78
Nominal unit shear capacity (v) per SDPWS Table 4.3A and 4.3C assuming 3"
WSP edge nailing, SPF framing, and blocked gypsum with 7" edge nailing: 755
(0.92)1370/2+250/2 = 755 plf
PSW capacity per SDPWS 4.3.3.5 = (v)(Li)(Co) (lbs) 10,600
Load (lbs) 5,370
Load < Capacity OK
Table W6.8 Bottom Story Shear Wall Edge Nail Spacing and Wall Length Summary
Building Elevation 1-2 1-1 1-B 1-A
Segmented 6" 20.0' 4" 13.6' 6" 20.0' 6" 20.0'
Seismic
Perforated 3" 16.5' 3" 16.5' 6" 22.8' 6" 25.8'
Segmented 6" 18.8' 4" 13.9' 4" 17.4' 6" 23.6'
Wind
Perforated 3" 19.9' 3" 22' 4" 20.5' 6" 28.0'
See shear wall detailing summary tables at the end of this section for a final
comparison of wind vs. seismic results.
Floor Framing
Floor Joists (WFCM 3.3.1.1)
Choose Floor Joists from Tables 3.18A-B
Table W6.9 Selection of Specie, Grade, Size, and Spacing for Floor Joists (Table 3.18B)
Specie Douglas Fir-Larch Hem-Fir Southern Pine Spruce-Pine-Fir
Spacing 16 16 16 16
Grade #1 #1 #1 SS
Size 2x10 2x10 2x10 2x10
Maximum Span 16'-5" 16'-0" 16'-1" 16'-0"
Blocking per
WFCM 3.3.5
Floor Framing
Floor Sheathing
Sheathing Spans (WFCM 3.3.4.1)
Choose Floor Sheathing from Table 3.14
Connections
Lateral Framing and Shear Connections (WFCM 3.2.1)
Wall Assembly (WFCM 3.2.1.3)
Top Plate to Top Plate
Table 3.1 Footnote 1 for WSP wall edge nailing spacing < 6"
4" nail spacing: 1.67 x 2 nails .......................................... 4-16d Commons per foot
3" nail spacing: 2.0 x 2 nails ............................................ 4-16d Commons per foot
Top Plate Intersection (Table 3.1): .................................................... 4-16d Commons each side joint
Top or Bottom Plate to Stud (Table 3.1 & 3.5A): ............................. 2-16d Commons per stud*
* See header design for any additional nailing required for king studs
Bridging to Floor Joist (Table 3.1): ...................................................... 2-8d Commons each end
Blocking to Floor Joist (Table 3.1): ...................................................... 2-8d Commons each end
Band Joist to Floor Joist (Table 3.1): ................................................... 3-16d Commons per joist
Floor Joist to Top Plate (Table 3.1): ..................................................... 4-8d Commons per joist
Blocking to Sill or Top Plate (Table 3.1): ............................................. 3-16d Commons each block
Note that nailing requirements are increased in many cases to maintain load path since shear wall
sheathing nailing is less than 6” o.c. at panel edges.
Connections (cont’d)
Lateral, Shear, and Uplift Connections (WFCM 3.2.1 and 3.2.2)
Wall Assembly to Foundation (WFCM 3.2.1.7 and 3.2.2.3)
Choose Sill Plate to Foundation Connection Requirements for Anchor Bolts Resisting Lateral,
Shear, and Uplift Loads from Table 3.2A for Wind and 3.3A for Seismic
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Stories supported by Foundation: ............................................................... 2
Sill plate size (based on Tables W6.1 and W6.2): ...................................... 2x6
Anchor Bolt Diameter: ................................................................................ 5/8 in.
Table W6.10 Assuming Crawl Space or Basement, determine maximum Anchor Bolt Spacing.
Building Wall Elevation 1-2 1-1 1-B 1-A
Sill plate line dimension (Lsw) 40' 40' 32' 32'
Building dimension perpendicular to sill plate (Table 3.2A) 32' 32' 40' 40'
S Tabulated number of anchor bolts to resist seismic shear loads (ss)
4 4 4 4
e (Table 3.3A4) (R+C+2F) (interpolated)
i Dead load adjustment per Table 3.3A Footnote 5 (Cdl) 1.14 1.14 1.14 1.14
s
Adjusted number of bolts ssa = (ss)(Cdl) 5 5 5 5
m
i Bolt spacing for seismic shear loads (bolts placed 1' from end of sill)
114" 114" 90" 90"
c sss = 12 (Lsw-2) / (#bolts-1)
Tabulated number of bolts to resist shear loads from wind
9 9 12 12
(Table 3.2A)(R+2F)
W Wall and Roof Height Adjustment (Table 3.2A Footnote 4) (CWRH) 0.91 0.91 0.91 0.91
i Minimum number of bolts to resist shear loads = Tabulated x CWRH 9 9 12 12
n Bolt spacing for wind shear loads (bolts placed 1' from end of sill)
57" 57" 32" 32"
d sws = 12 (Lsw-2) / (#bolts-1)
Max. bolt spacing to resist wind uplift loads (swu)
36" 36" 22"** 22"**
(Table 3.2C (end zones) & 3.4C)
Max. anchor bolt spacing (lesser of sws, swu, and sss) 36" 36" 22" 22"
**Calculated from WFCM Table 3.4C based on 16" o.c. outlooker spacing (horizontal projection) and 24"
outlooker overhang span with 2 wall dead loads subtracted (0.6 x 121 plf x 16/12 = 97 lbs) and
bottom/sill plate capacity from WFCM Commentary Table 3.2C. Table 3.4C = 671 lbs – 194 lbs (2 walls)
= 477 lbs. WFCM Commentary Table 3.2C calculations = 22". A 19.2" outlooker overhang span would
result in 26" spacing.
AMERICAN WOOD COUNCIL
68 First Story Design
Connections (cont’d)
Alternatively, use proprietary connectors with the following minimum capacities from Table 3.2,
Table 3.3, and Table 3.4C.
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Stories supported by Foundation: ............................................................... 2
Table W6.11 Assuming Crawl Space or Basement, determine required loads for proprietary
connectors.
Building Wall Elevation 1-2 1-1 1-B 1-A
Building dimension W or L L=40' L=40' W=32' W=32'
R=L/W or W/L for Table 3.3 (see Footnote 1) 1.0 1.0 1.25 1.25
S Tabulated seismic shear load (Table 3.3) R+C+2F
e (interpolated) 174 plf 174 plf 174 plf 174 plf
i
s Adjustment for other dead load case Footnote 3 (Cdl) 1.14 1.14 1.14 1.14
m
i Adjusted seismic shear load = tabulated seismic shear
c load (Cdl) 198 plf 198plf 198plf 198plf
Number of stories receiving lateral wind load
2 2 2 2
(Table 3.2)
Outlooker Spacing n/a n/a 16" 16"
Wind uplift (Table 3.4C) n/a n/a 671 lbs 671 lbs
W Wall Dead Load Reduction n/a n/a 194 lbs 194 lbs
i Adjusted Wind uplift (Table 3.4C) n/a n/a 477 lbs* 477 lbs*
n Wind uplift (Table 3.2(U)) 218 plf 218 plf
d Wind lateral load (Table 3.2(L)) ** ** ** **
R=L/W or W/L for Table 3.2 (see Footnote) 0.8 0.8 1.25 1.25
Tabulated Wind shear load (Table 3.2(S)) 427R 342 plf 342 plf 534 plf 534 plf
Footnote 3: Sheathing Type Adjustment per Table
0.60 0.60 0.74 1.0
3.17D (Cswa) – assuming PSW
Footnote 4: Wall and Roof Height Adjustment (CWRH) 0.91 0.91 0.91 0.91
Adjusted shear load = Tabulated (CWRH) / (Cswa) 519 plf 519 plf 657 plf 486 plf
* Assumes 24" outlooker overhang span. See Table W6.10 footnote for calculation basis. A 19.2"
outlooker would result in 343 lbs of uplift.
**Table 3.2 Footnote: Determine anchorage for Lateral Loads in foundation design per Section 1.1.4
(might include soil loads).
Connections (cont’d)
Uplift Connections (WFCM 3.2.2)
Wall Assembly to Foundation (WFCM 3.2.2.3)
Table W6.12 Wall to Foundation Uplift Strap Connection from Table A-3.4
Building Wall Elevation 1-2 1-1
Three second gust wind speed (700 yr) and Exposure category: 160 mph Exp. B
Framing Spacing 16 in.
W
i Roof Span 32 ft
n Tabulated number of 8d Common Nails required in each end of
d 1-1/4" x 20 gage strap every stud 4
No Ceiling Assembly nail increase (Footnote 3) 0
Required number of 8d Common Nails in each end of strap every
stud = Tabulated number of nails - Reductions + Increases 4*
*Non-loadbearing wall assemblies in accordance with Table W6.13 (3.2.6.3)
Table W6.13 Alternative proprietary connectors with the following minimum capacities
Building Wall Elevation 1-2 1-1 1-B 1-A
Loadbearing Walls - Tabulated minimum uplift connection capacity
479 lbs n/a
(Table 3.4)
Interior framing adjustment (Footnote 1) 1.0 n/a
Roof dead load reduction (Table 3.4, Footnote 2) = 0 since the attic
W 0 lbs n/a
i floor does not cover the entire second floor
n Wall-to-Wall and Wall-to-Foundation reduction -194 lbs -194 lbs
d (Table 3.4, Footnote 3) = [73 plf x 2 walls (16" / 12"/ ft) = 194 lbs]
Non-Loadbearing Walls - Tabulated minimum uplift connection
n/a 671 lbs
capacity (Table 3.4C)
Required minimum capacity of proprietary connector
= Tabulated minimum capacity with Adjustments 285 lbs 477 lbs*
* Assumes 24" outlooker overhang span. See Table W6.10 footnote for calculation basis. A 19.2"
outlooker would result in 343 lbs of uplift.
Connections (cont’d)
Uplift Connections (WFCM 3.2.3)
Wall Assembly to Foundation (WFCM 3.2.2.2 and 3.2.3)
Table W6.14 Alternative to metal straps on every stud - wood structural panels to resist wall plate
to wall stud uplift and shear from Table 3.4B
Building Wall Elevation 1-2 1-1 1-B 1-A
Three sec. gust wind speed (700 yr) and exp. category 160 mph Exp. B 160 mph Exp. B
Roof Span 32 ft n/a**
W Shear Wall Sheathing Thickness (see p.58) 15/32 in. 15/32 in. 15/32 in. 15/32 in.
i Shear Wall Type and Nailing: size and spacing (panel 8d comm. 8d comm. 8d comm. 8d comm.
n edges and field) (see Table W6.8) - SSW @ 6"/12" @ 4"/12" @4"/12" @ 6"/12"
d Number of Rows Required - SSW 2 2 2 2
Top & Bottom of Panel Nail spacing - SSW 4" 3" 3" 3"
Shear Wall Type and Nailing: size and spacing (panel 8d comm. 8d comm. 8d comm. 8d comm.
edges and field) (see Table W6.8) - PSW @ 3"/12" @ 3"/12" @4"/12" @ 6"/12"
Number of Rows Required - PSW n/a n/a 2 2
Top & Bottom of Panel Nail spacing - PSW NP 1
NP 1
3" 3"
1. WFCM Table 3.4B and SDPWS Table 4.4.1 are limited to no less than 4" panel edge spacing for
shear. Wall 1-1 require metal straps on every stud to resist uplift loads or use Segmented Shear Wall
nailing requirements.
** An engineered approach using 2015 SDPWS to design gable end wall (1-A & 1-B) WSPs to resist
combined uplift and shear is as follows:
1. Table W6.13 shows 343 lbs and 477 lbs for 19.2" and 24" outlooker overhang spans, respectively.
2. Use SDPWS Table 4.4.1 to determine the appropriate ASD uplift capacity for the specified shear wall
nailing of 8d common 6" panel edge spacing, 12" field spacing as follows:
• For 2 rows of nails at top and bottom of panel edges spaced at 4":
o ASD Uplift Capacity = 432 lbs (864 lbs/2) < 477 lbs (24"
outlooker overhang span) NG
o ASD Uplift Capacity = 432 lbs (864 lbs/2) > 343 lbs (19.2"
outlooker overhang span) OK
• For 2 rows of nails at top and bottom of panel edges spaced at 3":
o ASD Uplift Capacity = 648 lbs (1,296 lbs/2) > 477 lbs (24"
outlooker overhang span) OK
• Therefore 2 rows of 8d common nails spaced 3" at top and
bottom panel edges can be used for a 24" outlooker overhang
span – 4" for a 19.2" outlooker overhang span.
Additional detailing
• See WFCM Figure 3.2f (shown right) for appropriate panel edge
nail spacing (3.2.3.5).
• See Special Connections for connections around openings
(3.2.3.4).
• Anchor bolts with 3"x3" steel plate washers at 16" o.c. are
required (3.2.3.6).
• Determine sheathing splice requirements over common
horizontal framing members or at mid-stud height (3.2.3.7).
AMERICAN WOOD COUNCIL
2018 Wood Frame Construction Manual Workbook 71
Connections (cont’d)
Overturning Resistance (WFCM 3.2.4)
Hold-downs (WFCM 3.2.4.1)
Table W6.15 Calculate Hold-downs from Table 3.17F for Segmented and Perforated Shear Walls
Building Wall Elevation 1-2 1-1 1-B 1-A
Wall Height 9' 9' 9' 9'
Tabulated hold down connection capacity required –
2151 lbs 2151 lbs 2151 lbs 2151 lbs
seismic (Ts)
WSP Perimeter Edge Nail Spacing – seismic – SSW
6" 1.0 4" 0.68 6" 1.0 6" 1.0
& Hold-down adjustment per Footnote 1 (Cswa)
Adjusted hold-down capacity to account for
increased shear capacity (Tsa-ssw = (Ts) / (Cswa)) – 2151 lbs 3163 lbs 2151 lbs 2151 lbs
seismic - SSW
S Additional story hold-down requirements – seismic -
e SSW (see Table W5.12) 2151 lbs 2151 lbs 2151 lbs 2151 lbs
i
Total hold-down requirement for floor to foundation
s 4302 lbs 5314 lbs 4302 lbs 4302 lbs
(Tsa-ssw) – seismic - SSW
m
i WSP Perimeter Edge Nail Spacing – seismic – PSW 3" 0.53 3" 0.53 6" 1.0 6" 1.0
c & Hold-down adjustment per Footnote 1 (Cswa)
Adjusted hold-down capacity (Tsa-psw = (Ts) / (Cswa))
4058 lbs 4058 lbs 2151 lbs 2151 lbs
– seismic - PSW
Additional story hold-down requirements – seismic -
2151 lbs 2151 lbs 2151 lbs 2151 lbs
PSW (see Table W5.12)
Total hold-down requirement for floor to foundation
6209 lbs 6209 lbs 4302 lbs 4302 lbs
(Tsa-psw) – seismic - PSW
Tabulated hold-down connection capacity required –
3924 lbs 3924 lbs 3924 lbs 3924 lbs
wind (Tw)
WSP Perimeter Edge Nail Spacing – wind – SSW &
6" 1.0 4" 0.74 4" 0.74 6" 1.0
Hold-down adjustment per Footnote 1 (Cswa)
Adjusted hold-down capacity to account for
increased shear capacity (Twa-ssw = (Tw) / (Cswa)) - 3924 lbs 5303 lbs 5303 lbs 3924 lbs
wind
Additional story hold-down requirements – wind –
W SSW (Table W5.12) 3924 lbs 3924 lbs 3924 lbs 3924 lbs
i Total hold-down requirement for floor to foundation
n – wind – SSW (Twa-ssw) 7848 lbs 9227 lbs 9227 lbs 7848 lbs
d
WSP Perimeter Edge Nail Spacing – wind – PSW &
3" 0.60 3" 0.60 4" 0.74 6" 1.0
Hold-down adjustment per Footnote 1 (Cswa)
Adjusted hold-down capacity (Twa-psw = (Tw) / (Cswa))
6540 lbs 6540 lbs 5303 lbs 3924 lbs
- wind
Additional story hold-down requirements – wind –
3924 lbs 3924 lbs 3924 lbs 3924 lbs
PSW (Table W5.12)
Total hold-down requirement for floor to foundation
10464 lbs 10464 lbs 9227 lbs 7848 lbs
– wind – PSW (Twa-psw)
One hold-down can be used on each corner with corner studs connected to transfer shear as shown in
WFCM Figures 3.8a or 3.8b.
Connections (cont’d)
Sheathing and Cladding Attachment (WFCM 3.2.5)
Wall Sheathing (WFCM 3.2.5.2)
Choose Wall Sheathing Nail Spacing from Table 3.11
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Stud Spacing: .............................................................................................. 16 in.
Sheathing Type (wood structural panels, board or lap siding): .................. WSP
Connections (cont’d)
Special Connections (WFCM 3.2.6)
Connections around Wall Openings (WFCM 3.2.6.4)
Typical Window
Choose Header/Girder Connections based on loads from Table 3.7
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Roof Span: .................................................................................................. 32 ft
Header Span (Typical Window): ................................................................ 9 ft
Window (4' header) Adjusted Uplift Capacity (interpolated): .................... 583 lbs
Window (4' header) Tabulated Lateral Capacity: ....................................... 336 lbs
Window (3' header) Adjusted Uplift Capacity (interpolated): .................... 437 lbs
Window (3' header) Tabulated Lateral Capacity: ....................................... 252 lbs
Choose Window Sill Plate Connections based on loads from Table 3.8
Three second gust wind speed (700 yr) and Exposure category: ................ 160 mph Exp. B
Window Sill Plate Span: ............................................................................. 3 ft
Tabulated Lateral Connection Capacity - Each End of Window Sill: ....... 252 lbs
Note that the segmented shear wall detailing summaries show what could be done when summing hold-
down capacities from upper to lower stories. From a practical standpoint, hold-downs with different
capacities would likely not be used in the same shear wall line. Rather, the maximum hold-down capacity
would typically be specified for all to avoid installation errors. Also note that one hold-down can be used
on each corner of the building with corner studs connected to transfer shear as shown in WFCM Figures
3.8a or 3.8b.
Note that the segmented shear wall detailing summaries show what could be done when summing hold-
down capacities from upper to lower stories. From a practical standpoint, hold-downs with different
capacities would likely not be used in the same shear wall line. Rather, the maximum hold-down capacity
would typically be specified for all to avoid installation errors. Also note that one hold-down can be used
on each corner of the building with corner studs connected to transfer shear as shown in WFCM Figures
3.8a or 3.8b.