E2 External Moisture Amendment 6
E2 External Moisture Amendment 6
E2 External Moisture Amendment 6
Verification Methods
For New Zealand Building Code Clause
E2 External Moisture
Third Edition
E2
Status of Verification Methods and Acceptable Solutions
Verification Methods and Acceptable Solutions are prepared by the Ministry of Business, Innovation and Employment
in accordance with section 22 of the Building Act 2004. Verification Methods and Acceptable Solutions are for use in
establishing compliance with the New Zealand Building Code.
A person who complies with a Verification Method or Acceptable Solution will be treated as having complied with
the provisions of the Building Code to which the Verification Method or Acceptable Solution relates. However, using
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alternative ways to comply.
Users should make themselves familiar with the preface to the New Zealand Building Code Handbook, which describes
the status of Verification Methods and Acceptable Solutions and explains alternative methods of achieving compliance.
Defined words (italicised in the text) and classified uses are explained in Clauses A1 and A2 of the Building Code and in
the Definitions at the start of this document.
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2
Document Status
The most recent version of this document (Amendment 6), as detailed in the Document History, is approved by the Chief
Executive of the Ministry of Business, Innovation and Employment. It is effective from 14 February 2014 and supersedes all
previous versions of this document.
The previous version of this document (Errata 2) will cease to have effect on 14 August 2014.
People using this document should check for amendments on a regular basis. The Ministry of Business, Innovation and
Employment may amend any part of any Verification Method or Acceptable Solution at any time. Up-to-date versions of
Verification Methods and Acceptable Solutions are available from www.dbh.govt.nz
Date Alterations
Third Edition E2/VM1 effective from 1 July 2004 E2/AS1 effective from 1 February 2005
Amendment 2 Effective from 1 July 2005 p. 2 Document History, Document Status pp. 25-43, 45-47, 49, 50, 55-57, 59-67,
pp. 5-7, 9, 10 Contents 69-89, 93-100, 102, 103, 105-107,
pp. 13-16 References 111-119, 121-125, 127-135, 138,
pp. 17-20 Definitions 140-144, 146, 147, 149, 150,
pp. 21-24 E2/VM1 153-155, 157,163-169 E2/AS1
pp. 173, 174, 177, 178 Index
Amendment 4 Effective from 1 May 2008 p. 2 Document History, Document Status pp. 171-180 E2/AS2
until 31 January 2012 pp. 8 and 12 Contents p. 181 Index
pp. 13-14 References
Amendment 5 1 August 2011 p. 2 Document History, Document Status pp. 25-180 E2/AS1
pp. 5-12 Contents pp. 183-184,189-190 E2/AS2
pp. 13-16A References p. 191 E2/AS3
pp. 17-20 Definitions pp. 193-204 Index
pp. 21-24 E2/VM1
Errata 2 Effective from 24 December 2011 p. 2 Document History, Document Status pp. 29, 41, 43, 49, 55-57, 80, 81,
until 14 August 2014 p. 9 Contents 87, 91, 93, 94, 101, 106-108,
110-115, 117, 158, 160, 172, 176,
191 E2/AS1
Amendment 6 14 February 2014 p. 2A, Document History, Document Status p. 23, E2/VM1 1.5.1, 1.5.2, 1.5.3
p. 5, Contents pp. 36, 68, 172, 175, 175 E2/AS1 4.3.4,
pp. 13,15,16A References 8.3.4.2, Tables 20, 21, 22
p. 17, Definitions
Note: Page numbers relate to the document at the time of Amendment and may not match page numbers in current document.
2A
2B
Clause E2 EXTERNAL MOISTURE
SR2007/124
Performance
E2.3.1 Roofs must shed precipitated
moisture. In locations subject to
snowfalls, roofs must also shed
melted show.
E2.3.2 Roofs and exterior walls
must prevent the penetration of
water that could cause undue damp-
ness, damage to building elements,
or both.
E2.3.3 Walls, floors, and structural
elements in contact with, or in close
proximity to, the ground must not
absorb or transmit moisture in quan-
tities that could cause undue damp-
ness, damage to building elements,
or both.
E2.3.4 Building elements susceptible
to damage must be protected from
the adverse effects of moisture enter-
ing the space below suspended
floors.
E2.3.5 Concealed spaces and cavi-
ties in buildings must be constructed
in a way that prevents external mois-
ture being accumulated or trans-
ferred and causing condensation,
fungal growth, or the degradation of
building elements.
Amend 3
Jun 2007
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 21 June 2007
3
EXTERNAL MOISTURE C lause E2
SR2007/124
Amend 3
Jun 2007
4 21 June 2007 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
C o n t e n ts E 2 /VM1 & AS1 /AS2 /AS3 EXTERNAL MOISTURE
Contents
Amend 2
Page 1.4 Specific design 26 Jul 2005
1.5 Qualifications 26
References 13
2.0 General 26
Definitions 17
2.1 Weathertightness 26
Verification Method E2/VM1 21 2.2 Materials 26
1.0 Cladding systems of buildings, 21 2.3 Systems versus materials 26
including junctions with windows,
2.4 Cladding finish colours 26
doors and other penetrations
2.5 Maintenance – general 27
1.1 General 21
Amend 5
2.5.1 Regular maintenance 27 Aug 2011
1.2 Scope 21
3.0 Weathertightness Risk Factors 27
1.3 Specimen details 21
3.1 Establishing the risk 27
1.4 Test procedure 22
3.1.1 Definitions of risk 27
1.4.1 Preconditioning 22
3.1.2 The risk score 27
1.4.2 Series 1 Static pressure water 22 Amend 5
Amend 2
Jul 2005 penetration Aug 2011
6 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
C o n t e n ts EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
7
EXTERNAL MOISTURE Contents
Amend 5
9.6.4 Maintenance 138 Aug 2011
8 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
C o n t e n ts EXTERNAL MOISTURE
Table 3: Suitable wall claddings 31 Table 18D: Corrosion protection to lintels 115
Table 4: Risk matrix example 1 – south face 32 Table 18E: Masonry veneer lintel sizes 116
(minimum)
Table 5: Risk matrix example 2 – south 33
elevation Table 19: Control joints for flush-finished
fibre cement 153
Table 6: Risk matrix example 3 – south 34
elevation Table 20: Material selection 172
Table 8: Maximum catchment areas for 61 Table 22: Compatibility of materials 175
valley gutters subject to run-off
Table 9: Maximum catchment areas 62 Table 23: Properties of roof underlays 176
Errata 2
above penetrations and wall underlays Dec 2011
Table 10: Minimum pitches for masonry 63 Table 24: Fixing selection for wall 177
tiles claddings
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
9
EXTERNAL MOISTURE Contents
Figure 16: Junction with wall for 53 Figure 43: Ridge to hip flashings 80
cantilevered timber deck Figure 44: Apron flashing and change in 80
Figure 17A:Level thresholds for enclosed 55 pitch for profiled metal
decks Figure 45: Eaves and roof/wall ridge for 81
Figure 17B:Level thresholds for ground 56 profiled metal
level Figure 46: Ridge and hip flashings for 81
Figure 17C:Door sills for cavity construction 56A profiled metal
Figure 17D:Door sills for direct fix 56B Figure 47: Barge flashings for profiled metal 82
Figure 18: Enclosed balustrade – 57 Figure 48: Parallel apron flashings for 83
bottom of cladding profiled metal
Figure 19: Stanchion fixing 58 Figure 49: Profiled metal stopends 84
Figure 20: Spreader for roof discharge 60 Figure 50: Parallel hidden gutter for 85
Amend 2
Figure 21: Penetration support 62 profiled metal Jul 2005
Figure 22: Catchment area for penetrations 62 Figure 51: Valley gutters for profiled metal 85
Figure 23: Masonry tile ridge 64 Figure 52: Internal gutter for profiled metal 86
Amend 2
Figure 24: Barge for masonry tile 64 Figure 53: Flashing for small pipes 87
Jul 2005
Figure 25: Timber fascia eaves for 65 Figure 54: Soaker flashing for pipe 87
masonry tile penetrations
Figure 26: Apron details for masonry tile 65 Figure 55: Soaker flashing for other 88
penetrations
Figure 27: Valley for masonry tile 66
Figure 56: Falls in membrane roofs 91
Figure 28: Roof/wall ridge for masonry tile 66
and decks
Figure 29: Pipe penetration for masonry tile 66
Figure 57: External corner in upstand 91
Figure 30: Abutment at framed penetration 67
Figure 58: Internal corner in upstand 92
for masonry tile
Figure 59: Roofing penetration in membrane 92
Figure 31: Flashing to framed penetration 67
for masonry tile Figure 60: Pipe penetration in membrane 92
Figure 33: Metal tile fixings 69 Figure 62: Junctions with walls for membrane 94
Figure 34: Ridge or hip flashings for 70 Figure 63: Rainwater head and scupper 95
metal tile opening in membrane
Figure 35: Apron flashings for metal tile 70 Figure 64: Gutters and outlets in membrane 96
Figure 36: Eaves and barge for metal tile 71 Figure 65: Levels and garage openings 97
Figure 37: Hidden and valley gutter 71 Figure 66: Cavity base closer/vermin
flashings for metal tile proofing 100
Figure 38: Profiled metal profiles 74 Figure 67: Cavity spacers 100
Figure 39: Corrugated and trapezoidal fixings Figure 68: General pipe penetration 102
and sheet lap 77 Figure 69: General meterbox and similar 103
Amend 2
Figure 40: Typical trough profile fixings 78 penetrations
Jul 2005
Figure 41: Soft edge flashing 79 Figure 70: General inter-storey junction 103
Amend 5 Amend 5
Aug 2011
Figure 42: Trapezoidal notched flashing 79 Figure 71: General sealing of head flashing 104 Aug 2011
10 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
C o n t e n ts EXTERNAL MOISTURE
Figure 72A: General window and door 106 Figure 89: Aluminium corners in fibre 135
opening for direct fixed cement weatherboards
Figure 72B: General window and door 107 Figure 90: Windows and doors in fibre 136
opening with drainage cavity cement direct fixed
Figure 73A: Vertical control joint 108 weatherboards
Figure 73B: Masonry veneer height 109 Figure 91: Windows and doors in fibre 137
limitations cement weatherboards on cavity
Figure 73C: Masonry veneer window 110 Figure 92: Barge for vertical profiled metal 140
and door installation Figure 93: Bottom of cladding for vertical 140
profiled metal
Figure 73D: Masonry veneer details 111
Figure 94: Corners for vertical profiled 141
Figure 73E: Masonry veneer details 112
metal
Figure 74: Types of stucco cladding 117
Figure 95: Windows and doors for vertical 142
Figure 75: Bottom of stucco cladding 119 profiled metal
Figure 76: Windows and doors in 120 Figure 96: Corner flashings for horizontal 143
stucco cladding profiled metal
Figure 77: Corner soakers for bevel-back 122 Figure 97: Barge for horizontal profiled 144
weatherboards metal
Figure 78: External corners for horizontal 123 Figure 98: Bottom of cladding 144
weatherboards
Figure 99: Windows and doors for 145
Figure 79: Internal corners for horizontal 124 horizontal profiled metal
or vertical weatherboards on cavity
Figure 80: External corners for vertical 125 Figure 100: Window and door flashings 146
weatherboards for profiled metal
Figure 81: Windows and doors for direct 126 Figure 101: Balustrade for vertical 147
fixed bevel-back weatherboards profiled metal
Figure 82: Windows and doors for direct 127 Figure 102: Balustrade for horizontal 147
fixed rusticated weatherboards profiled metal
Figure 83: Windows and doors for 128
direct fixed vertical shiplap Figure 104A: Vertical uPVC joints for fibre 149
weatherboards cement sheet
Figure 84: Windows and doors for direct 129 Figure 104B: Internal corners for fibre 149
fixed board and batten cement sheet
weatherboards Figure 105: Vertical timber batten joints 150
Figure 85: Windows and doors for bevel- 130 for fibre cement sheet
back weatherboards on cavity
Figure 107: Horizontal joints for direct 151
Figure 86: Windows and doors for 131
fixed fibre cement
rusticated weatherboards
on cavity Figure 108: Horizontal joints for fibre 152
cement sheet on cavity
Figure 87: Joints in fibre cement 133
weatherboards Amend 5
Amend 5
Figure 110: Flush-finished joints for fibre 153 Aug 2011
Aug 2011 Figure 88: External corners in fibre 134 cement sheet
cement weatherboards
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
11
EXTERNAL MOISTURE Contents
Figure 111: Vertical movement control 154 Figure 9.2: Head details 185
joint for flush-finished fibre A) Timber joinery with 185
cement sheet timber-framed wall insert
Figure 113: Flush-finished external corners 155 B) Aluminium joinery with 185
for fibre cement sheet timber-framed wall insert
C) Timber joinery with 186
Figure 114: Soffits for flush-finished fibre timber lintel
cement sheet 155 D) Aluminium joinery with 186 Amend 4
Figure 115: Windows and doors for direct 156 timber lintel May 2008
Figures – E2/AS2
Figure 4.1: Footing dimensions 181
and general details
Figure 5.11: Soffit to wall junction 182
A) Flat soffit 183
B) Angled soffit 183
Amend 5 Figure 5.12: Timber-framed gable to 184
Aug 2011
earth wall
12 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
R e f e r e n ce s E 2 /VM1 & AS1 /AS2 /AS3 EXTERNAL MOISTURE
References
For the purposes of New Zealand Building Code (NZBC) compliance, the Standards and documents
Amend 6
referenced in these Verification Methods and Acceptable Solutions (primary reference documents) Feb 2014
must be the editions, along with their specific amendments, listed below. Where these primary
reference documents refer to other Standards or documents (secondary reference documents),
which in turn may also refer to other Standards or documents, and so on (lower-order reference
Amend 4
documents), then the version in effect at the date of publication of these Verification Methods and
Amend 6
May 2008 Acceptable Solutions must be used. Feb 2014
Where quoted
Standards New Zealand
Amend 5
Aug 2011 AS/NZS 1734: 1997 Aluminium and aluminium alloys – Flat sheet, AS1 4.3.2, 8.3.4.3,
coiled sheet and plate 8.4.3.3, 9.6.3.3
Amends AS/NZS 2269.0: 2008 Plywood – Structural AS1 8.5.3,
2 and 5
9.3.6.1, 9.8.2
NZS 2295: 2006 Pliable, Permeable Building Membranes AS1 8.1.5, Table 23
Amend 6 AS/NZS 2728: 2013 Prefinished/prepainted sheet metal products for AS1 4.2.1, 8.3.4.1,
Feb 2014
interior/exterior building applications 8.3.4.2, 8.3.4.3,
– Performance requirements 8.4.3.1,8.4.3.3, 9.6.3.1,
9.6.3.3, Table 20
Amend 5
Aug 2011 AS/NZS 2904: 1995 Damp-proof courses and flashings
Amend 6
Feb 2014 Amend: 1 AS1 4.3.10, 9.2.4
AS/NZS 2908: Cellulose-cement products
Part 2: 2000 Flat sheet AS1 9.3.6.2, 9.5.2,
9.7.2
NZS 3602: 2003 Timber and wood-based products for use in building AS1 9.1.10, 9.4.2,
9.4.9, 9.7.3, 9.8.2,
10.2,Table 23
NZS 3604: 2011 Timber framed buildings Definitions, VM1 1.1, 1.2,
AS1 1.1, 1.3, 4.1.3, 4.2.1,
7.2.1, 8.3.4.1, 8.4.3.1,
8.5.1, 9.1.3.1, 9.1.3.5,
9.2.1, 9.2.3, 9.2.7.1,
9.2.9, 9.3.2, 9.6.3.1,
Amend 4
Table 1, Table 2, Table 4, May 2008
Table 5, Table 6, Table 18,
Table 18A, Table 20
and Table 24
Amend 5
Aug 2011
AS2 Figure 5.11 a) and b)
NZS 3617: 1979 Specification for profiles of weatherboards, fascia AS1 9.4.1.1
boards, and flooring
AS/NZS 4020: 2005 Testing of products for use in contact with AS1 8.1.1
drinking water
Amend 5
Aug 2011
Where quoted
Amend 5
Aug 2011
NZS 4206: 1992 Concrete interlocking roofing tiles AS1 8.2.1, 8.2.3
Amend 5
Aug 2011 NZS 4211: 2008 Specification for performance of windows VM1 1.2, AS1 9.1.10
NZS 4217 Pressed metal tile roofs AS1 8.3.3
Part 1: 1980 Specification for roofing tiles and their accessories
Part 2: 1980 Code of practice for preparation of the structure and
the laying and fixing of metal roofing tiles
Amend 5
Aug 2011 SNZ HB 4236: 2002 Masonry veneer wall cladding Definitions,
AS1 Table 3
NZS 4251: Solid plastering
Amend 5
Aug 2011 Part 1: 2007 Cement plasters for walls, ceilings and soffits AS1 9.3.2, 9.3.4.1,
9.3.4.2, 9.3.6.1, 9.3.6.2
AS/NZS 4256 Plastic roof and wall cladding materials AS1 4.3.1
Part 2: 1994 Unplasticized polyvinyl chloride (uPVC) building sheets
Amend 5
Aug 2011
AS/NZS 4284: 2008 Testing of Building Facades VM1 1.1, 1.4, 1.4.2,
1.4.3, 1.4.4
NZS 4298: 1998 Materials and workmanship for earth buildings AS2 5.1.8, 9.7.2,
Amend: 1 Figure 4.1, Figure 9.2
a), b), c) and d)
NZS 4299: 1998 Earth buildings not requiring specific design AS2 1.0, 1.1
Amend: 1
NZS 4431: 1989 Code of practice for earth fill for residential AS2 Figure 4.1
development
Amend 4 Amend: 1
May 2008
AS/NZS 4534: 2006 Zinc and zinc/aluminium-alloy coatings on steel wire AS1 9.1.8.5
Amend 5
Aug 2011 AS/NZS 4680: 2006 Hot-dip galvanized (zinc) coatings on fabricated AS1 9.9.4.1,
ferrous articles Table 20
AS/NZS 4858: 2004 Wet area membranes AS1 9.7.7.1, 9.9.4.4,
Amend 5
Aug 2011 9.9.10.1
14 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
R e f e r e n ce s E 2 /VM1 & AS1 /AS2 /AS3 EXTERNAL MOISTURE
Where quoted
Standards Australia
AS 1366 Rigid cellular plastics sheets for thermal insulation
Part 3: 1992 Rigid cellular polystyrene – Moulded (RC/PS-M) AS1 9.9.3.1
Part 4: 1989 Rigid cellular polystyrene – Extruded (RC/PS-E) AS1 9.9.3.1
Amend 6
Amend 5 AS 1397: 2011 Continuous hot-dip metallic coated steel sheet and strip AS1 4.3.4, Table 20 Feb 2014
Aug 2011
– Coatings of zinc and zinc alloyed with aluminium and
magnesium
Amend 6
Feb 2014 Amend: 1
AS 1566: 1997 Copper and copper alloys – Rolled flat products AS1 4.3.6
AS 1804: 1976 Soft lead sheet and strip AS1 4.3.7
AS 2049: 2002 Roof tiles AS1 8.2.1
AS 2050: 2002 Installation of roof tiles AS1 8.2.3
AS 3566 Self-drilling screws for the building and construction
industries
Amend 5
Aug 2011 Part 2: 2002 Corrosion resistance AS1 8.4.8, 8.4.9,
9.6.6, Table 20
Amend 5
AS 3730 Guide to the properties of paints for buildings AS1 9.3.7, 9.4.9, 9.5.6,
Aug 2011 9.7.3.1, 9.7.4, 9.8.9,
9.9.3, 9.9.6.3
Amend 5
Aug 2011
Part 6: 2006 Solvent-borne – Exterior – Full gloss enamel
Part 7: 2006 Latex – Exterior – Flat
Part 8: 2006 Latex – Exterior – Low-gloss
Amend 2
Part 9: 2006 Latex – Exterior – Semi-gloss
Jul 2005 Part 10: 2006 Latex – Exterior – Gloss
AS 4046 Methods of testing roof tiles
Amend 5
Aug 2011 Part 9: 2002 Determination of dynamic weather resistance VM1 2.1, AS1 8.2.3
British Standards Institution
BS 6538: 1987 Air permeance of paper and board AS1 Table 23
Part 3: 1987 Method for determination of air permeance using
the Garley apparatus
Amend 5
Aug 2011
BS EN 988: 1997 Zinc and zinc alloys. Specification for rolled flat AS1 4.3.8
products for building
Where quoted
American Society for Testing and Materials
Amend 5
Aug 2011
ASTM C1549: 2009 Standard Test Method for Determination of Solar AS1 2.4
Reflectance Near Ambient Temperature Using a
Portable Solar Reflectometer
Amend 5
Aug 2011
ASTM D1667: 2005 Standard Test Specification for Flexible Cellular AS1 9.1.10.7
Materials – Vinyl Chloride Polymers and Copolymers
(Closed-Cell Foam)
Amend 5
Aug 2011 ASTM D2240: 2005 Standard Test Method for Rubber Property AS1 9.1.10.7
Amend 5
Aug 2011 ASTM D6134: 2007 Standard Specification for Vulcanised Rubber Sheets AS1 4.3.9, 8.5.4
Used in Waterproofing Systems
Amend 5
Aug 2011 ASTM E96: 2005 Standard Test Methods for Water Vapour AS1 Table 23
Transmission of Materials
ASTM E104: 2002 Standard Practice for Maintaining Constant AS1 10.3.2
Relative Humidity by Means of Aqueous Solutions
Amend 5
Aug 2011
ASTM E2098: 2000 Standard Test Method for Determining Tensile AS1 9.9.3.2
Breaking Strength of Glass Fibre Reinforcing Mesh
for Use in Class PB Exterior Insulation and Finish
Systems (EIFS), after Exposure to a Sodium
Hydroxide Solution
ASTM E2134: 2001 Standard Test Method for Evaluating the Tensile- AS1 9.9.6
Adhesion Performance of an Exterior Insulation
and Finish System (EIFS)
Amend 5
Aug 2011 ASTM G154: 2006 Standard Practice for Operating Fluorescent Light AS1 9.1.10.7
Apparatus for UV Exposure of Nonmetallic Materials
Amend 5
Aug 2011
ASTM G155: 2005 Standard Practice for Operating Xenon Arc Light AS1 9.1.10.7
Apparatus for UV Exposure of Nonmetallic Materials
Building Research Association of New Zealand
Amend 5
Aug 2011 BRANZ Bulletin 330: 1995 Thin flooring materials – 2 AS1 10.3.2
Preparation and laying. Appendix 1
Amend 2 BRANZ EM 4: 2005 Evaluation method for jointing systems for flush AS1 9.7.4, 9.7.10.2
Jul 2005
finished fibre cement sheet
Amend 2
Jul 2005
BRANZ EM 5: 2005 Evaluation method for adhesives and seam tapes AS1 8.5.4
for butyl and EPDM rubber membranes
Amend 5
Aug 2011 BRANZ EM 6: 2010 Evaluation method for window and door support AS1 9.1.10.5
mechanisms or bars
BRANZ Bulletin 411: 2001 Recommended timber cladding profiles AS1 9.4.1.1
16 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
R e f e r e n ce s E 2 /VM1 & AS1 /AS2 /AS3 EXTERNAL MOISTURE
Where quoted
SCION
Measurement of moisture content of wood AS1 10.3.1
Amend 5
Aug 2011
Other Organisations
Federal Specification Elastomeric type, cold applied single component AS1 4.5.2, 8.4.11.1,
Amend 5
Aug 2011 Standard for caulking, sealing, and glazing in buildings, 9.1.6, 9.1.9.3, 9.2.8.2,
TT-S-00230C building areas (plazas, decks, pavements), and 9.5.3.2, 9.6.7, 9.9.3,
other structures 9.9.8
EIMA 101.91: 1992 EIFS Industry Members Association. Standard Guide AS1 9.9.3.2
for resin of resin coated glass fiber mesh in exterior
insulation and finish systems (EIFS), Class PB.
ICBO Evaluation Acceptance criteria for flashing materials AS1 4.3.11, 9.1.5,
Services Inc AC148 9.9.4.4
ISO 9223: 1992 Corrosion of metals and alloys; corrosivity of AS1 4.2.1, 8.3.4.1,
Amend 5
Aug 2011 atmospheres; classification 8.4.3.1, 9.6.3.1, Table 20
ISO 11600: 2002 Building Construction – Jointing products AS1 4.5.2, 8.4.11.1,
Amend 5 Classification and requirements for sealants 9.1.6, 9.1.9.3, 9.2.8.2,
Aug 2011
9.5.3.2, 9.6.7, 9.9.3, 9.5.3.2, 9.6.7, 9.9.3,
9.9.8
ISO/TS 15510: 2003 Stainless steels – chemical composition AS1 4.3.5
New Zealand Metal Roof and Wall Cladding Code of Practice: 2008 AS1 4.3, 4.5.1, 4.5.2,
Amend 5
Aug 2011
New Zealand Metal Roofing Manufacturers Inc. 8.1.6.2, 8.3.1, 8.4.1,
8.4.12, 8.4.14, 8.4.15,
8.4.16.2, 8.4.17
Amend 5
Aug 2011
Cement & Concrete Association of New Zealand
Amend 6
Feb 2014 CCANZ – CP01: 2014 Code of Practice for weathertight concrete AS3 1.0
and concrete masonry construction
Definitions
This is an abbreviated list of definitions for words or terms particularly relevant to these Verification
Amends
2 and 6 Methods and Acceptable Solutions. The definitions for any other italicised words may be found in
the New Zealand Building Code Handbook.
Damp-proof membrane (DPM) A sheet EIFS (Exterior Insulation and Finish System).
material, coating or vapour barrier, having A polystyrene sheet-based cladding system
a low water vapour transmission, and that uses mesh reinforced polymer-
used to minimise water and water vapour modified cement-based or polymer-based
penetration into buildings. Usually applied plaster base coats and a protective top
Amend 5
Aug 2011 against concrete in contact with the ground. coating.
(Also known as a concrete underlay.) Electrolytic corrosion Galvanic corrosion
Deck An open platform projecting from an commonly resulting from the contact of two
exterior wall of a building and supported dissimilar metals when an electrolyte such
by framing. A deck may be over enclosed as water is present.
internal spaces, or may be open Enclosed balustrade A timber-framed barrier
underneath. Refer also Enclosed deck. with cladding across all exposed faces.
Also known as a balcony. Refer also Parapet.
Amend 5
Aug 2011
Direct fixed A term used to describe a wall Enclosed deck A deck, whether over an
cladding attached directly to the wall interior or exterior space, that has an
framing, without the use of a drained cavity. impermeable upper surface and is closed
Dormer or dormer window A framed on the underside. May also be known as
structure that projects from a sloping roof, a balcony.
and has a window at its outer end. Envelope complexity The categorisation
Drained cavity A cavity space, immediately of the complexity of the total building
behind a wall cladding, that has vents at the envelope into one of four classes, depending
base of the wall. Also known as a drained on the particular features of the building as
Amend 2 and vented cavity and referred to in this specified in this Acceptable Solution.
Jul 2005
Acceptable Solution as a cavity or drained EPDM (Ethylene Propylene Diene Monomer)
Amend 5
Aug 2011 cavity. A thermosetting synthetic rubber used as a
A drained cavity assists drying by allowing resilient part of a sealing washer, or as a
water which occasionally penetrates the roof membrane.
wall cladding system to drain to the exterior Expansion joint A joint designed to prevent
of the building, and any remaining moisture damage by accommodating movement.
to dry by evaporation. Where this See also Control joint.
Acceptable Solution requires a nominal
External wall Any vertical exterior face of
20 mm drained cavity, the depth shall be
a building consisting of primary and/or
between limits of 18 mm and 25 mm.
secondary elements intended to provide
For definition of masonry veneer cavity protection against the outdoor environment.
Amend 2
Jul 2005 refer to SNZ HB 4236. Amend 5
Aug 2011
Drip edge Fold(s) applied to the edge of a
Finished ground level (FGL) The level of the
horizontal metal flashing to deflect moisture
ground against any part of a building after
away from the cladding system below. Amend 5
all backfilling and/or landscaping and/or Aug 2011
Refer also Bird’s beak and Kick-out.
surface paving has been completed.
Amend 5 Dwang A short (usually horizontal) member
Aug 2011
Flashing A component, formed from a rigid
fixed between framing timbers. Also known
or flexible waterproof material, that drains
as nogging.
or deflects water back outside the cladding
Eaves That part of the roof construction, system.
Amend 5
Aug 2011 including cladding, fascia and eaves gutter
Flexible flashing tape A flexible self-adhesive
(spouting), that extends beyond the exterior
waterproof tape. Usually used as an
face of the wall. Amends
accessory for wall underlays, to seal 2 and 5
18 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
D e f i n i tio n s EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
19
EXTERNAL MOISTURE D efinitions
Stanchion A connecting device, fixed into Waterproof and waterproofing The complete
the structure of a building, that provides and total resistance of a building element to
support for handrails, aerials and similar the ingress of any moisture.
structures. Weathertightness and weathertight Terms
Stopend A turn-up at the upper edge of used to describe the resistance of a
profiled metal cladding, or at the end of building to the weather.
gutters and some types of flashings. Weathertightness is a state where water is
COMMENT: prevented from entering and accumulating
A stopend assists the control of moisture by ensuring behind the cladding in amounts that can
any moisture reaching the edge of the roofing is cause undue dampness or damage to the
deflected from further entry. building elements.
Storey That portion of a building included COMMENT:
between the upper surface of any floor and The term weathertightness is not necessarily the same
the upper surface of the floor immediately as waterproof.
above, except the top storey shall be that However, a weathertight building, even under severe
portion of a building included between the weather conditions, is expected to limit moisture
upper surface of the topmost floor and the ingress to inconsequential amounts, insufficient to
ceiling or roof above. cause undue dampness inside buildings and damage to
building elements. Moisture that may occasionally enter
Stucco A wall cladding system formed from is able to harmlessly escape or evaporate.
reinforced solid plaster over a rigid or non-
Wetwall The exterior cladding on a wall with a
rigid backing.
drained cavity.
Stud A vertical framing timber.
Wind zone Categorisation of wind force
Transverse flashing A roof flashing that runs experienced on a particular site as determined
across the roof slope, at right angles to the in NZS 3604, Section 5.
roof cladding profile.
COMMENT:
Trapezoidal A type of profiled metal cladding
Maximum ultimate limit state speeds are:
with symmetrical or asymmetrical crests, Low wind zone = wind speed of 32 m/s
with troughs between the crests. Medium wind zone = wind speed of 37 m/s
High wind zone = wind speed of 44 m/s
Trough profile A type of profiled metal Very high wind zone = wind speed of 50 m/s
cladding comprising vertical ribs with flat, Extra high wind zone = wind speed of 55 m/s. Amend 5
Aug 2011
or lightly profiled pans between the ribs. Specific design is required for wind speeds greater Amend 2
Also known as ribbed, secret fixed or tray than 55 m/s. Jul 2005
profile.
Underlay The material used behind a roof
or wall cladding. Refer Wall underlay and
Amend 5
Aug 2011 Roof underlay.
Valley gutter A gutter running down the
valley formed by the intersection of two
pitched roof surfaces.
Amend 5
Aug 2011 Wall refer External wall.
Wall underlay A building paper, synthetic
Amend 5
Aug 2011 material or rigid sheathing used as part
of the wall cladding system to assist the
control of moisture by ensuring moisture
which occasionally penetrates the wall
cladding is directed back to the exterior of
the building.
20 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
Ve r i f i c a tio n Me th o d E 2 /VM1 EXTERNAL MOISTURE
This Verification Method is for determining 1.2.2 This Verification Method may also be
compliance with NZBC E2.3.2 of cladding used for individual buildings that comply with
systems and associated window and door (a) to (d) above, and that are designed for
junctions only, for buildings of importance a specific wind pressure up to a maximum
Levels 1 or 2 as described in Table 1.1(a) ultimate limit state (ULS) of 2500 Pa.
of NZS 3604. COMMENT:
The tests in this Verification Method shall While the test specimens used for this Verification
be undertaken in a test facility with IANZ Method may include window and door units, it is only
the junctions of these elements with other cladding
or equivalent accreditation for testing
elements that are assessed in the test.
the weathertightness of claddings to the
procedures of AS/NZS 4284, and as used
to establish the performance criteria detailed
1.3 Specimen details
in Paragraph 1.4 Test Procedures. The minimum size of the wall cladding
specimen to be tested shall be 2.4 m x 2.4 m.
COMMENT:
The weathertightness testing of AS/NZS 4284 is Any cladding system within an Extra High
modified in this Verification Method for generic domestic- wind zone or subject to a specific design wind
oriented cladding because the Standard was developed pressure up to ULS 2500 Pa that relies on this
primarily for testing specific, non-absorptive facades and
Verification Method shall have a rigid underlay
curtain wall systems on high-rise commercial buildings.
installed in accordance with Paragraph 9.1.7 of
E2/AS1. In either of these two circumstances,
1.2 Scope a rigid underlay is not necessary for the
1.2.1 The scope of this Verification Method verification tests as a flexible wall underlay
shall be restricted to buildings that: may suffice – unless the cladding to be tested
a) are in accordance with the scope of specifically includes a rigid air barrier as part of
Paragraph 1.0 of E2/AS1, and within the specified system.
the wind zones covered by Section 5 of If the cladding system is never to be used
NZS 3604, and with building elements penetrating the
b) have claddings that include a drained and exterior surface walls, then the specimen
vented cavity of nominal 20 mm minimum shall include the details from Class 1. In all
depth with minimum ventilation opening other cases, specimens with the details of
of 1000 mm2 /m at the foot, including any Class 2 shall be tested, where the classes are
claddings that require a rigid wall underlay described below:
in accordance with Paragraph 9.1.7.2 Class 1: Cladding systems where only vertical
of E2/AS1, and joints are required, and having no penetrations
c) include window and door units that are through the cladding. Testing shall include
manufactured to comply with the relevant vertical joints, internal and external corners
Amend 5
requirements of NZS 4211, and of the external wall junctions, and footer and
Aug 2011
header termination systems.
Class 2: All other cladding systems to be used
Amend 5
within the scope of this document. Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
21
EXTERNAL MOISTURE Verification Method E2/V M1
22 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
Ve r i f i c a tio n Me th o d E 2 /VM1 EXTERNAL MOISTURE
Amend 5
Aug 2011
1.4.5 Series 3 'Wetwall Test' 1.6 Pro-forma for test details
1.4.5.1 Repeat Paragraph 1.4.3 with an air The pro forma attached as Appendix 1 to this
pressure of 50 Pa, applied across the wetwall Verification Method may be used to provide
only, for 15 minutes. specifiers with a summary of test details
1.4.5.2 Non-compliance shall be the presence and results.
of water (as defined in Paragraph 1.4.5.3)
after carrying out the tests in Paragraphs 2.0 Pitched roofing systems over a
1.4.2 and 1.4.3, and the subsequent 'water ventilated roof space of 15° pitch
management' tests (or evidence of any water) or more
on the removed surfaces of the cavity.
2.1 AS 4046 Part 9 provides a Verification
1.4.5.3 Water which is able to penetrate to
Method for determining compliance with
the back of the wetwall through introduced
NZBC E2.3.2 of any tiled roofing system
defects and joints shall be controlled. It may
of 15° pitch or more above a roof space
contact battens and other cavity surfaces,
(i.e. not a skillion roof). Compliance is based
but no water shall be transferred to the
on comparison of performance with a control
plane of the wall underlay, cavity air sealing
roofing system described in the Standard.
or structural framing due to a design or
Compliance is achieved where the water
systemic failure. Water that may arrive on the
penetration is less than, or equal to, the
underlay due to an 'isolated blemish' may be
control sample. This test is also a Verification
disregarded. No water may drip through an air-
Method for other ventilated roofing systems
space within the cavity where it is possible for
or skylights with a pitch of 15° or more above
water to impact on a surface in the cavity and
a roof space.
splash onto the wall underlay. However, the
spattering of water into the cavity through the
3.0 Skillion roofs and commercial
introduced defects shall be ignored.
and industrial roofing
During the Wetwall Test, water is allowed to
spatter up from the footer flashing, provided 3.1 No specific method has been adopted
Amend 5
it is not held above any cavity obstruction. for verifying compliance of skillion roofs Aug 2011
Amend 6
Feb 2014
Amend 5
Series 1: Static Water Penetration
Aug 2011 Test pressure 455 Pa
Duration 15 minutes
Amend 5 Series 1: Cyclic Water Penetration
Aug 2011 Test pressure 455–910 Pa
Duration 5 minutes
Amend 5
Aug 2011
Comments:
24 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Claddings also required to perform as bracing must G6, are outside the scope of this Acceptable
comply with NZS 3604. Where a drained cavity is Solution.
used, specific testing can be used to demonstrate that
a cladding on cavity battens can provide the required COMMENT:
Amend 5
Aug 2011 bracing resistance. Cavities in such circumstances must be specifically
designed for both weathertightness and acoustic
performance.
1.1.1 Attached garages
Attached garages that are integral with the 1.3 Provisions for snow Amend 2
Jul 2005
weathertightness envelope of the building
Specific design for preventing the ingress
are included within the scope of this
Amend 5 of snow melt water is required when the
Aug 2011 Acceptable Solution. Refer to Paragraph 9.1.3.4.
open ground snow load Sg, as defined in
Amend 5
NZS 3604, exceeds 1.0 kPa, and the roof is Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
25
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
of adjoining building elements to achieve a complete Aug 2011
Amend 5
Colour cards from some coating manufacturers may
Aug 2011 Manufacturers’ recommendations may include information include reflectance values.
additional to that shown in this Acceptable Solution.
26 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011 2.5 Maintenance – general 3.0 Weathertightness Risk Factors
Maintenance shall be carried out as necessary
COMMENT:
to achieve the required durability of materials,
Analysis of inspection reports from leaking buildings
components and junctions.
shows that a high incidence of leaks is associated with
The extent and nature of necessary junctions within, and penetrations through, the building
maintenance is dependent on the: envelope. It also shows serious problems are more
commonly associated with claddings that have limited
a) Type of cladding or components used, capacity to drain and dry out any water that gets behind Amend 5
Aug 2011
them, when a leak occurs.
b) Position of cladding or components on the
building, This Acceptable Solution addresses these problems
in two ways:
c) Geographical location of the building, and
a) By providing details for common junctions and
d) Specific site conditions. penetrations of the building envelope, and
washed by rain as smoother surfaces, so will require selected from Table 3 according to the risk
more regular manual washing. scores, or the highest risk score may be used
However, it is important that high pressure water is for all walls.
not directed at sensitive junctions such as window
surrounds and other flashings. Great care must be taken
to avoid water being driven past anti-capillary gaps and
flashings into the wall cavities.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
27
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011 Figure 1: How to assess risk
Paragraph 3.1
Amend 5
Aug 2011 3.3 Wall claddings
Step Two: Assess the drawings
The following wall cladding systems are
Assess Each for each external face to
covered in this Acceptable Solution: External Face determine the risk score for
Against Risk each risk factor. These are:
a) Masonry veneer Paragraph 9.2 Factors Wind zone
b) Stucco Paragraph 9.3 Number of storeys
Roof/wall intersection
c) Timber weatherboards Paragraph 9.4 design
Eaves width
d) Fibre cement weatherboards Paragraph 9.5 Envelope complexity
Amend 2 Deck design
Jul 2005 e) Profiled metal wall claddings Paragraph 9.6 Refer Table 1.
f) Fibre cement sheet Paragraph 9.7
g) Plywood sheet Paragraph 9.8 Step Three: Complete the “Building
Complete the envelope risk matrix”
h) EIFS Paragraph 9.9. Building (Table 2) for each face
Envelope Risk of the building.
Amend 5
Aug 2011
Other wall claddings are outside the scope of Matrix Table
It is possible for different
this Acceptable Solution. elevations to have different
risk scores.
28 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
29
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011 Table 2: Building envelope risk scores
Paragraph 3.1.2, Figure 1
Risk severity
score
score
score
score
Risk factor LOW MEDIUM HIGH VERY HIGH (1) Subtotals for
each risk factor
Amend 5
Aug 2011 Wind zone (per NZS 3604)(1) 0 0 1 2
Number of storeys 0 1 2 4
Roof/wall intersection design 0 1 3 5
Eaves width 0 1 2 5
Envelope complexity 0 1 3 6
Deck design 0 2 4 6
(Enter the appropriate risk severity score for each risk factor in the score Total risk score
columns. Transfer these figures across to the right-hand column. Finally, add up for use in Table 3:
the figures in the right-hand column to get the total risk score.)
Amend 5 NOTE: (1) For buildings in Extra High wind zones, refer to Tables 1 and 3 for rigid underlay and drained cavity
Aug 2011 requirements.
30 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
31
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
The examples have been selected to show a range of For this example, the calculations have been done for
design complexities, features and materials. Refer also the south elevation, and this face scores as very low
Amend 5
Aug 2011
to Guide to the Risk Matrix. risk. A similar risk score would result for all elevations
of this building.
3.4.1 Example 1
The first example illustrates the use of the risk
matrix for a simple traditionally-styled building. 3.4.1.1 Cladding options
As all faces score low, cladding options from
Table 3 are:
a) Direct fixed claddings:
Amend 5
i) Timber weatherboards – all types shown Aug 2011
Figure 2: Risk matrix example 1 ii) Fibre cement weatherboards
iii) Vertical profiled metal – corrugated and
symmetrical trapezoidal only
Amend 5
iv) Fibre cement sheet – not flush-finished Aug 2011
v) Plywood sheet
Risk severity
score
score
score
score
32 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
The eaves are less than 450 mm wide, and the site is in
a High wind zone.
Risk severity
score
score
score
score
Eaves width 0 1 2 2 5 2
Envelope complexity 0 1 1 3 6 1
Deck design 0 2 2 4 6 2
Amend 5
Total risk score: 12 Aug 2011
Amend 2
3.4.2.1 Cladding options – south and west b) Wall cladding with a nominal 20 mm Jul 2005
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
33
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
3.4.2.2 Cladding options – north and east iv) Fibre cement sheet
elevations v) Plywood sheet
Cladding options from Table 3, for east and vi) EIFS, and
Amend 2
north faces, are: b) Wall cladding with a nominal 20 mm Jul 2005
3.4.3 Example 3
The third example illustrates the use of the
risk matrix for a complex building.
Amend 2
Specific design may result in the building consent
Jul 2005 authority possibly:
a) Needing more details to be provided,
Amend 2
b) Requiring more inspections during construction,
Jul 2005 c) Requiring a third party audit of the design.
Risk severity
score
score
score
score
34 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005 b) Wall cladding with a nominal 20 mm 4.2.1 Environment
drained cavity:
Flashing materials shall be selected according
i) Masonry veneer (with 40 mm cavity)
to the relevant exposure conditions as defined
ii) Stucco
in Table 20 to minimise corrosion.
iii) Horizontal profiled metal – corrugated
Amend 2
Jul 2005 and trapezoidal only
iv) Rusticated weatherboards
v) Fibre cement weatherboards Amend 5
COMMENT: Aug 2011
vi) Fibre cement sheet
The exposure zone in which a building is located can
vii) Plywood sheet affect the durability of flashings.
viii) EIFS
Exposure zones are defined in NZS 3604, based on the
ix) Bevel-back weatherboards. likely exposure to wind-driven sea-salt. Corrosion due
to geothermal or corrosive industrial atmospheres, as
4.0 Flashings defined in NZS 3604, require specific design.
Amend 5 Amend 5
Aug 2011 Aug 2011
Amend 2
Jul 2005
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
35
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
4.2.2 Surrounding materials 4.3.2 Aluminium flashings
Metals which are in contact in locations where Aluminium flashings shall be a minimum
they will become wet, or where water can thickness of 0.7 mm, and formed from 5000
Amend 2
flow over metals or certain plastics onto series in accordance with AS/NZS 1734. Jul 2005
COMMENT:
Manufacturers of uPVC flashings which have a proven
performance in use may be able to show compliance
with NZBC Clause B2 Durability as detailed in B2/VM1. Amend 2
Jul 2005
b) In compliance with AS 1566, and Exposed flashings such as barge and ridge
Amend 2
flashings are to be fixed along both edges. Jul 2005
c) Alloy, designation C11000 or C12200.
COMMENT:
4.3.7 Lead sheet flashings
Fixings that penetrate flashings should be avoided
Lead sheet flashings shall: where possible. Amend 5
Aug 2011
underlay or roof underlay, and be used only in Code of Practice for further edge treatments.
Amend 5
Aug 2011 fully concealed applications.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
37
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
4.5.2 Metal flashing joints a) Rivets used for joining and sealing laps
Where metal flashings require to be joined, the shall be spaced at a maximum of 50 mm
centres, and be:
method shall be as shown in Figure 6. Joins of
i) compatible with the flashing material as
metal flashings shall have the following features:
per Table 21 and Table 22, and
Figure 5: Typical metal flashing edge treatments ii) sealed against moisture, or
Amend 5
Paragraphs 4.5.1, 4.5.2, 4.6, 6.4, 7.4.4, iii) of a sealing type or blind rivet, Aug 2011
9.0, 9.1, 9.6.7
b) Expansion joints shall be provided for joined
flashings with a combined length exceeding:
i) 12 metres for light coloured steel and
stainless steel. 8 metres for dark
coloured steel,
ii) 8 metres for copper,
Amend 2
iii) 8 metres for aluminium. Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
38 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Where the pitch of the flashing is 15° or less 4.6.1 Overlap with roof claddings
at the join, the lap at the join shall be 200 4.6.1.1 Apron flashing cover over metal
Amend 2 mm minimum and the flashing underneath roofing
Jul 2005
the lap shall have a hook at the edge,
a) Transverse flashing:
g) Lap joins on other metal flashings shall be Refer to Figure 7 for example of use. The
sealed using a neutral cure silicone sealant apron shall have:
Amend 2
in conjunction with mechanical fasteners. i) for notched turn-downs, a gap between Jul 2005
The sealant shall comply with: the flashing and the pan of the roof
i) Type F, Class 20LM or 25LM of cladding. The gap shall be a maximum
Amend 2
ISO 11600, or of 5 mm, and Jul 2005
ii) low modulus Type II Class A of Federal ii) a minimum effective cover to roof
Specification TT-S-00230C. cladding, excluding any soft edge or
turn-down to the flashing, as shown in
COMMENT:
Table 7.
Further information may be found in the New Zealand
Metal Roof and Wall Cladding Code of Practice for joints b) Parallel flashing:
Amend 5 in metal flashings.
Aug 2011 Refer to Figure 48 for example of use.
The apron shall:
4.6 Flashing overlaps and upstands i) be dimensioned to suit the roof cladding
Overlaps and upstands to flashings shall be profile,
as specified in this paragraph and Table 7, ii) for profiled metal roof cladding, cover at
unless specifically shown otherwise. Refer least two crests, (turned-up edge to full
to Paragraph 8.1 to Paragraph 9.9 for crest height constitutes a crest), and
Amend 2
requirements for specific claddings. iii) for profiled metal roof cladding, Jul 2005
Where a turn-down to the cover flashing for a) For notched turn-downs of the flashing
profiled metal claddings is required, use: leave a gap between the flashing and the
roof cladding. The gap shall be a maximum
a) A soft edge flashing for corrugated profiles, or Amend 2
of 5 mm. Jul 2005
b) A notched turn-down or soft edge flashing
b) There shall be a minimum effective cover
for trapezoidal profiles with rib height not
Amend 5 to roof cladding, excluding any soft edge
Aug 2011 exceeding 30 mm and/or rib centres not
or turn-down to the flashing, in accordance
exceeding 200 mm, or
with Table 7.
c) A notched turn-down for trapezoidal profiles
with rib height exceeding 30 mm and/or rib 4.6.1.3 Change in metal roof pitches
centres exceeding 200 mm, or Refer to Figure 44 for example of use.
d) A notched turn-down for trough profiles. a) There shall be a minimum effective lap
Where a notched turn-down is used there under roof cladding in accordance with
shall be a gap between the edge of the Table 7, with a hem at upper edge. Amend 2
Jul 2005
flashing and the pan of the roof cladding. b) The apron cover over the roof cladding shall
Amend 2
Jul 2005 The gap shall be a maximum of 5 mm. be in accordance with Table 7.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
39
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Type Description All (1) Situation 1 (2) Situation 2 (3) Situation 3 Figure
minimum minimum (3a) reference
mm mm minimum (as example)
mm
Aprons: Figure 7 and
Transverse flashing
general 130 (4) 200 (4) 200 mm Figure 44
over roofing
(X values)
Parallel flashing over Two crests, finish in next trough – Figures 47,
roofing refer 4.6.1.1b) 48 (Y values)
Ridges/ Transverse flashing Figures 43,
Refer Aprons: general
hips over roofing 45b, 46
Changes Upper lap under 250 mm min. Not permitted Figure 44
in roof roofing under E2/AS1
pitches
Transverse flashing
Refer Aprons: general
over roofing
Barges Overlap to barge Figure 47
50 (8) 70 (8) 90 mm
board (Z values)
Cappings Overlaps to cladding 50 (8) 70 (8) 90 mm Figure 10
(Z values)
Slope to top: parapet 5° min. Figures 10,
and balustrade 11, 12, 130
– metal capping
Slope to balustrade 10° min. Figures 117,
– flush-finished EIFS 129, 130
and fibre cement(5)
Roof Overlaps to roofing
or Deck Refer Aprons: general
to Wall
– See Lap under cladding Figures 7, 26,
membranes above 75 mm min. 90 mm 30, 35, 37,
below 44, 48, 50
Clearance below
35 mm min.
cladding
Amend 5
Aug 2011 Total upstand 110 mm min.
40 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e pta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
41
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
42 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Errata 2
Dec 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
and Table 7, depending on the: direct water out from the wall cladding onto
i) wind zone and, the roof cladding and gutter.
ii) pitch of the roof.
Amend 2
Jul 2005
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
43
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Amend 5
It is important to ensure the wall cladding behind eaves
Aug 2011 gutters/spoutings, barges and fascias is protected by the
surface coating to prevent moisture penetration through
the unsealed cladding.
44 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
6.0 Parapets
COMMENT:
Vertical corrugated profiled metal is considered to have
Amend 5 drainage capabilities the equivalent of drained cavities.
Aug 2011
6.1 Limitations
This Acceptable Solution does not cover parapet
Amend 5
Aug 2011
cappings that use stucco, EIFS and flush-
finished fibre cement materials.
6.2 General
Amend 5
Aug 2011
Parapets shall be constructed as shown in
Figure 10, and shall comply with the following
requirements:
a) Timber for framing and cavity battens shall
comply with B2/AS1,
b) Sloped packers under cappings shall be
polystyrene or timber treated to B2/AS1,
or minimum 9 mm H3 plywood on packers,
and
c) Framing shall be fully enclosed with wall
underlay or roof underlay, in accordance
Amend 2
Jul 2005 with Table 23 for the specific cladding.
d) claddings shall be installed over a cavity
Amend 5
Aug 2011 in accordance with Paragraph 9.1.8.
Details for specific wall cladding systems
are given in Paragraph 9.0.
Specific requirements for enclosed
balustrades are given in Paragraph 7.4.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
45
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 5
Aug 2011
46 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
6.4 Metal cappings d) All cappings shall have drip edges. The
details shown in Figure 5 are acceptable
minimum drip edges for parapets,
e) Cappings shall be separated from
Metal cappings installed over parapets and underlying timber by roof underlay as
enclosed balustrades, shall be as outlined in shown in Figure 10,
Paragraphs 6.0 and 7.4, and comply with the
Amend 5
following requirements: f) Lengths of capping shall be joined as
Aug 2011
shown in Figure 9 (b) or Figure 9 (d),
a) Tops of cappings shall be free of any
penetrations, g) External corners of cappings shall be as
shown in Figure 9 (e),
b) Slope of top shall be 5° (1:12) minimum,
h) Expansion joints shall be provided for
c) The cover at the sides of the capping shall joined cappings with a combined length
be in accordance with Table 7, exceeding:
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
In-plane junctions require specific design of flashing
Aug 2011 arrangements.
48 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Errata 2
Dec 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 5
Aug 2011
50 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Figure 13 deleted
Figure 14: Threshold separations
Paragraphs 7.1, 7.3, 8.5.6, Figures 17A,
56, 62 and 64
For enclosed decks, the vertical separation Fixings for stringers shall be in accordance
Amend 5
Aug 2011 between the opening threshold level and the with NZS 3604.
upper surface of the finished deck surface
COMMENT:
shall be a minimum of 100 mm.
Separating decks from buildings reduces the risk of
water penetration into the framing.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
51
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
52 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
53
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
provided against the wall or balustrade iv) 1:200 minimum fall along length of channel Amend 2
Jul 2005
cladding. towards a drainage outlet,
b) Grating, in accordance with Tables 21 and
7.3.1.2 Timber removable surface 22, over the channel, that: Amend 5
Aug 2011
Timber decking shall be over framing i) is supported independently of the door
supported off the deck membrane as shown frame,
in Figure 17A, with spacing in accordance ii) is removable to allow access for cleaning,
Amend 5
Aug 2011 with B2/AS1. iii) is specifically designed to accommodate
No fixings shall penetrate the underlying deck imposed loads,
membrane. iv) has gaps sized to prevent the wheels
of wheel chairs or mobility aids entering
COMMENT:
or being trapped, and
v) has a continuous gap of 12 mm
Tiled boards or structural pavers sitting on proprietary
Amend 5 minimum from door frame and wall
Aug 2011
supports can be adjusted according to level changes in
the underlying deck surface. cladding, and
54 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Errata 2
Dec 2011
Errata 2
Dec 2011
Errata 2
Dec 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
55
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Errata 2
Dec 2011
Amend 5
Aug 2011
56 24 December 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
56A
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Enclosed balustrade-to-wall junctions shall be capping. The drip edge to the deck side of
flashed to direct water clear of the outside face the capping shall be a bird’s beak as shown
of the cladding system using a saddle flashing as in Figure 5.
shown in Figures 11 and 12. COMMENT:
Amend 5
Aug 2011
A bird’s beak drip edge will avoid danger of injury
resulting from the sharp edge of a kick-out.
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
7.4.5 Stanchions
Amend 5
Aug 2011 Stanchions for handrails, signs, television
aerials or similar structures shall be side-fixed
through the cladding system into framing,
as shown in Figure 19. These fixings are not
included for stucco, EIFS or profiled metal in
this Acceptable Solution.
Fixing shall be to vertical surfaces only. The
Amend 5
Aug 2011
sealant shall be compatible with the washer.
Amend 5
Aug 2011
58 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
8.1 General
8.1.1 Weathertightness Amend 5
Aug 2011
Roof claddings shall meet the requirements of 8.1.4 Fixings
NZBC E2.2, and be specified and constructed Fixings shall be as specified in Paragraph 8.2
in accordance with the provisions of Paragraph to Paragraph 8.5.
8.1.2 to Paragraph 8.5.
Materials for fixing roof claddings and flashings,
COMMENT: where necessary, shall be selected from
Amend 5
For roofs used to collect water for human consumption, Tables 20, 21 and 22 to minimise corrosion. Aug 2011
Amend 5
Aug 2011 refer AS/NZS 4020.
COMMENT:
8.1.2 Limitations The use of stainless steel fixings is not recommended
by steel manufacturers for use with coated steel in
severe marine and industrial environments, as they are
The following roof cladding systems are considered to cause deterioration. Amend 5
Aug 2011
covered in this Acceptable Solution:
8.1.5 Roof underlays
a) Masonry tiles Paragraph 8.2
Roof underlays shall be to Table 23 and
b) Pressed metal tiles Paragraph 8.3
NZS 2295, and be either:
c) Profiled metal roof claddings Paragraph 8.4 Amend 2
• R1 heavy weight kraft, or Jul 2005
d) Membrane roofing Paragraph 8.5.
• R2 self supporting kraft.
Other roof claddings are beyond the scope of
Underlays shall be:
this Acceptable Solution.
• Layed with minimum numbers of laps
8.1.3 Maintenance
• Lapped at all side and end laps by minimum
Maintenance of claddings shall be carried out
Amend 5 150 mm
Aug 2011 as necessary to achieve the expected durability
of the materials – refer to Paragraph 2.5. • Run horizontally for roof pitches below 10°
• Run horizontally or vertically for roof pitches
above 10°
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
59
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
e) Have a minimum cross sectional area Design calculations for a specific roof may allow larger
catchment areas per spreader to be used.
of 2500 mm2
The alternative to a spreader is to direct an upper level
f) Be designed to overflow water to the downpipe into a rainwater head.
outside.
Amend 5 The ends of spreaders should be blocked off where a
Aug 2011 sideways flow of water is against laps in roof claddings.
60 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
61
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Amend 5
Aug 2011
62 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
8.2 Masonry Tiles Table 10: Minimum pitches for masonry tiles
Paragraph 8.2.3, Figure 25
resembling slates, shakes and shingles. Rafter length, tile profile and wind zone all affect the
allowable minimum pitch of a tile roof. Rafters longer
8.2.2 General than in Table 10 may require the addition of underlay.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 2
Jul 2005 Figure 24: Barge for masonry tile
Paragraph 8.2.6
Amend 2
Jul 2005
Amend 5 Amend 2
Aug 2011 Jul 2005
64 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 27: Valley for masonry tile Figure 28: Roof/wall ridge for masonry tile
Paragraphs 8.2.6 and 8.1.6.2 Paragraph 8.2.6
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
66 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
67
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005 8.3.4.3 Aluminium
Exposure zones are defined in NZS 3604, based on the Figure 32: Metal tile profiles
likely exposure to wind-driven sea-salt. Corrosion due Paragraph 8.3.5
to geothermal or corrosive industrial atmospheres, as
defined in NZS 3604, require specific design.
8.3.4.2 Steel
Steel for the manufacture of pressed metal
Amend 2
Jul 2005 tile and flashing systems shall:
a) have a base metal thickness (BMT) of
Amend 5
Aug 2011 0.39 mm minimum,
Amend 5
Amend 6
Feb 2014 b) be grade G300 or G250, Aug 2011
COMMENT:
Metal tile manufacturers supply pre-folded or formed
Amend 5
accessories and recommendations for their installation. Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
70 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
Figure 37: Hidden and valley gutter flashings for metal tile
Amend 2
Jul 2005 Paragraphs 8.1.6.2, 8.3.3, 8.3.8, Figure 51
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
8.3.10 Roof penetrations
Pipe penetrations shall be flashed using
EPDM flashings similar to that shown for
Amend 5
Aug 2011 masonry tiles, Figure 29.
COMMENT:
Use purpose-made preformed rooflights and ventilators
supplied by the manufacturer of the tiles where
available.
72 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005 8.4 Profiled Metal Roof Cladding COMMENT:
The exposure zone in which a building is located can
affect the durability of flashings.
8.4.1 Limitations Exposure zones are defined in NZS 3604, based on the
likely exposure to wind-driven sea-salt. Corrosion due
This Acceptable Solution is limited to the
to geothermal or corrosive industrial atmospheres, as
following types of profiled metal roof cladding: defined in NZS 3604, require specific design.
a) Profiled as outlined in Paragraph 8.4.4, Exposure zones are based on AS/NZS 2728.
b) Valley gutters that do not change direction AS/NZS 2728 lists atmospheric classes derived from
Amend 5
Amend 5 ISO 9223 for Australia and New Zealand. Aug 2011
Aug 2011 in plan,
c) Not curved, and 8.4.3.2 Steel Amend 5
Aug 2011
d) With sheets no more than 18 metres long. Materials for the manufacture of profiled steel
Amend 2
roof cladding shall: Jul 2005
Amend 2 COMMENT:
Jul 2005 a) have a BMT of 0.4 mm minimum
If curved profiled metal sheet is used, the radius of
the curve may affect durability. Specific design is b) be grade G550, or G300 for rolled, crimped,
required, and manufacturers and the New Zealand or trough profile roofing
Metal Roof and Wall Cladding Code of Practice
should be consulted for recommendations. c) be selected for corrosion protection
according to the intended exposure zone as
8.4.2 General shown in Table 20.
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 2
8.4.3.3 Aluminium
Jul 2005
Aluminium for the manufacture of profiled
aluminium roofing shall comply with
COMMENT:
AS/NZS 1734, and be a minimum:
Refer to Paragraph 1.5 for qualification of installers.
a) Base metal thickness (BMT) of 0.7 mm,
Amends
2 and 5 b) 5000 series.
8.4.3 Materials
Amend 5
8.4.3.1 Choice of metal Pre-painted aluminium roofing shall have Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
are shown in Figure 38, and consist of: end laps, pitches shall be:
a) Corrugated – curved with a crest height of a) Corrugated – not less than 8° (1:7).
Amends
2 and 5 16.5 mm minimum,
b) Trapezoidal – symmetrical or asymmetrical b) Trapezoidal – not less than:
with a minimum crest height of 19 mm, i) 4° (1:14) where the crest height is less
and for asymmetrical a flat or lightly profiled than 27 mm, or
pan width of 210 mm maximum between ii) 3° (1:20) where the crest height is
Amend 5
crests, and 27 mm or higher.
Aug 2011
c) Trough profile – not less than 3° (1:20). Amend 5
c) Trough profile – with vertical ribs at a Aug 2011
Amends
2 and 5
Amend 5
Aug 2011
74 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Table 11: Steel corrugate profiled roofing – 0.4 mm BMT and minimum profile height 16.5 mm
Maximum spans and fixing patterns. Refer to Paragraph 8.4.6
End span Intermediate span Low and Medium High and Very High Extra High
0.4 0.6 C2 C2 C2
0.6 0.9 C2 C2 C1
0.8 1.2 C2 C1 C1
Table 12: Steel corrugate profiled roofing – 0.55 mm BMT with minimum profile height 16.5 mm
Maximum spans and fixing patterns. Refer to Paragraph 8.4.6
End span Intermediate span Low and Medium High and Very High Extra High
0.4 0.6 C3 C3 C3
0.6 0.9 C3 C3 C3
0.8 1.2 C3 C3 C3
1.15 1.6 C3 C3 C2
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
Table 13: Steel trough profile roofing – 0.55 mm
BMT with profile height 46 mm Screw fixing is recommended for metal roofing as Amend 5
Aug 2011
minimum, and pan width 210 mm there is less likelihood of the fixing ‘backing out’ than
maximum(2) with a nail. Amend 2
Jul 2005
Maximum spans. Refer to Paragraph 8.4.6
The spacing requirements for fixings are conservative,
and a specific design may produce a more optimum
All building wind zones spacing, especially with the use of load-spreading
Maximum span of roof cladding washers. Consult roofing manufacturers for information.
mm
8.4.8.1 Fixing requirements
End span Intermediate
span Amend 2
Jul 2005
1100 1600 Fixings shall: Amend 5
Aug 2011
NOTE: (1) Trough profile with 0.4 mm BMT
steel is excluded from this
a) Be fixed through crests,
Acceptable Solution b) Penetrate purlins by a minimum of 40 mm
(2) For profile heights and pan widths for nail fixings and 30 mm for screw fixings, Amends
outside this range, refer to supplier’s 2 and 5
literature for fixing patterns and spans c) Include sealing washers of:
Amend 5 i) neoprene (having a carbon black content
Aug 2011
of 15% or less by weight),
ii) profiled washer and EPDM washer
where required to allow for expansion
Amend 2
Jul 2005
of the profiled metal roof cladding.
Amend 2
Jul 2005
COMMENT:
Figure 39: Corrugated and trapezoidal fixings
It is recommended that access to the roof is limited to
and sheet lap
Amend 2 within 100 mm of purlin lines to avoid damaging the
Jul 2005 Paragraphs 8.4.8, 9.6.6, Tables 20, 22 and 24
roof cladding.
8.4.7 Underlay
All profiled metal long-run roofing shall have
Amend 5 a roof underlay installed to Table 23. See
Aug 2011
Paragraph 8.1.5 for installation details.
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
76 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Table 14: Steel trapezoidal profiled roofing – 0.4 mm BMT and profile height 27 mm minimum(1),
and minimum 5-rib profiles
Maximum spans and fixing patterns. Refer to Paragraph 8.4.6
End span Intermediate span Low and Medium High and Very High Extra High
0.4 0.6 T2 T2 T1
0.6 0.9 T2 T1 T1
0.8 1.2 T2 T1 T1
1.2 1.8 SED SED SED
Table 15: Steel trapezoidal profiled roofing – 0.55 mm BMT, profile height 27 mm minimum(1)
and minimum 5-rib profiles
Maximum spans and fixing patterns. Refer to Paragraph 8.4.6
End span Intermediate span Low and Medium High and Very High Extra High
0.4 0.6 T2 T2 T2
0.6 0.9 T2 T2 T2
0.8 1.2 T2 T2 T2
1.2 1.8 T2 T1 T1
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Where Table 16 requires profiled washers, Aug 2011
Amends Amend 2
2 and 5 Jul 2005
8.4.10 Allowance for expansion
8.4.11.1 Fixing flashings
Allowance shall be made for expansion of
corrugated and trapezoidal roof cladding as a) When fixing flashings to the structure, use
shown in Table 16. screws as for roofing (see Paragraph 8.4.8).
78 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
COMMENT:
The use of stainless steel fixings is not recommended
by steel manufacturers for use with coated steel, in
severe marine and industrial environments, as they are
Amend 5
Aug 2011
considered to cause deterioration.
Amend 2
Jul 2005
Amend 2
g) Apron flashing – parallel flashing to profile
Jul 2005 as shown in Figure 48.
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Figure 43: Ridge to hip flashings Aug 2011
Amend 5 Paragraphs 8.4.11 and 8.4.12
Aug 2011
Amend 2
Jul 2005
COMMENT:
Reduced cover for barge and apron flashings may be
applicable for specifically designed roofs in low wind
Amend 2
Amend 2 zones. Jul 2005
Jul 2005
Refer to the New Zealand Metal Roof and Wall Cladding Errata 2
Dec 2011
Code of Practice for additional guidance on ridge to hip
Amend 5 flashings.
Aug 2011
Errata 2
Dec 2011
Amend 2
Figure 44: Apron flashing and change in pitch for profiled metal
Jul 2005 Paragraphs 4.5, 8.4.11, 8.4.12, Table 7
Amend 2
Jul 2005
Amend 5
Aug 2011
80 24 December 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Figure 45: Eaves and roof/wall ridge for profiled metal
Jul 2005 Paragraphs 4.5, 8.4.11, 8.4.12, Table 7
Errata 2
Dec 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 2 Figure 46: Ridge and hip flashings for profiled metal
Jul 2005 Paragraphs 4.4, 4.5, 8.4.11, 8.4.12, Table 7
Amend 2
Jul 2005
Amend 2
Jul 2005 Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
82 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
shall have stopends as shown in Figure 49 profile roofing shall be turned down at gutters,
for trapezoidal and trough profile metal roof where the roof pitch is less than 10°.
Amend 5
Aug 2011
cladding, where: The turn-down shall be 30° from the plane of
a) The roof pitch is less than 25°, or the sheet.
b) The building is in a High/Very High/Extra High COMMENT:
wind zone. Specific tools are available and should be used to turn
up or turn down ends. Care should be taken to ensure
the sheet does not split.
Refer to the New Zealand Metal Roof and Wall Cladding Amend 2
Code of Practice for guidance on methods. Jul 2005
Amend 5
Aug 2011
8.4.15 Profile closure
Figure 49: Profiled metal stopends
Paragraph 8.4.13, Figure 92
COMMENT:
Refer to the New Zealand Metal Roof and Wall Cladding
Code of Practice for guidance.
COMMENT:
Refer to the New Zealand Metal Roof and Wall Cladding
Code of Practice for additional guidance on sizing,
materials and fixing.
Amend 5
Aug 2011
Amend 5
Aug 2011
84 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005 Figure 50: Parallel hidden gutter for profiled metal
Paragraphs 4.3, 4.5, 8.1.6.2 and 8.4.16
Amend 2 Amend 5
Jul 2005 Aug 2011
Amend 2
Jul 2005
Amend 5 Amend 2
Aug 2011 Jul 2005
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 5
Aug 2011
86 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
Errata 2 Amend 2
Dec 2011 Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 5
Aug 2011
88 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
COMMENT:
Amend 5
Amend 5 The compatibility of LOSP-treated timber must be Aug 2011
Aug 2011
c) Internal gutters with a minimum fall of 1 in checked with membrane suppliers.
100, with no cross seams in the gutters, If using plywood containing copper-based preservatives,
and check the compatibility of adhesives and membranes
with copper with the product manufacturers.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
If the clearance of the cladding from the deck or roof
surface is at the minimum of 35 mm, give an overlap
of 115 mm to the cladding.
90 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 2
Jul 2005
Errata 2
Dec 2011 Amend 5
Aug 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 58: Internal corner in upstand Figure 59: Roofing penetration in membrane
Paragraph 8.5.8, Figures 62 and 64 Paragraphs 8.5.8 and 8.5.9
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
Amend 5
Aug 2011
Amend 5
8.5.9 Penetrations
Aug 2011
Penetrations through membrane roofs and
decks shall be as shown in Figure 59 and
Figure 60.
92 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Errata 2
Dec 2011
Amend 2
Jul 2005
Errata 2
Dec 2011
Amend 2
Jul 2005
Errata 2
Dec 2011 Amend 5
Aug 2011
COMMENT:
Any fixing of posts into membrane roofs or decks will
Amend 2
Jul 2005 require specific design.
8.5.10 Gutters
Deck gutters and internal outlets shall be
Amend 5
constructed as shown in Figure 64. Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 2
Jul 2005
Errata 2
Dec 2011
Amend 5
Aug 2011
94 24 December 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
96 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
Amend 5
rigid underlays and drained cavities – refer Timber floor Refer Note 1) 100 175 502)
Aug 2011
to Table 3. NOTE: 1) Refer to NZS 3604 for requirements.
2) Cladding to extend minimum 50 mm below
9.1.2 Maintenance
bearer or lowest part of timber floor framing. Amend 5
Aug 2011
Amend 5
Aug 2011
9.1.3.1 Concrete slabs
Maintenance of wall claddings shall be carried
out as necessary to achieve the expected Slab levels shall be set to allow reinstatement
durability of the material – refer to Paragraph 2.5. of final landscaped ground levels as outlined in
Figure 65 and Table 18.
COMMENT:
NZS 3604 may require greater ground clearances
9.1.3 Bottom of cladding
depending on floor type and materials.
Separations, clearances to ground level, and The likely final landscaped ground levels are to be taken
overlaps shall be as shown in Figure 65 and into account when planning foundations and earthworks
Table 18. to avoid reductions to the minimum ground clearances
Amend 5
in the finished building. Aug 2011
Clearances to roof claddings and decks shall
be minimum 35 mm – refer to Table 7 and
9.1.3.2 Masonry veneer clearances
Figure 18.
The height of the floor slab above finished
Clearances shall be measured to:
ground level shall be in accordance with
a) The finished plane of any adjacent Figure 73D and as shown in Table 18.
Amend 5
Aug 2011
horizontal surface, or
b) The top surface of any adjacent sloped or
Amend 5
Aug 2011 horizontal apron flashing.
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
9.1.3.3 Bottom of wall claddings for concrete At ground floor level, the base of the cladding
ground slabs (except masonry veneer) system shall:
Amend 5
Aug 2011
At concrete slab level, the base of the cladding a) Overlap the timber floor structure by
system shall be as shown in Table 18, and: 50 mm minimum, and
a) Finish a minimum of: b) For walls with direct fixed claddings,
i) 100 mm above a paved surface, or be offset horizontally from a concrete
Amend 5
Aug 2011 ii) 175 mm above finished unpaved surface, foundation wall by a minimum of 6 mm
b) Overlap the concrete slab by 50 mm, and c) Have no direct connection between sub-
Amend 5
c) Be offset horizontally by a minimum of floor spaces and drained cavities. Aug 2011
Amend 5
Aug 2011 6 mm for direct fixed claddings to prevent COMMENT:
capillary action. Where claddings require drained cavities, care must be
taken to ensure air from the subfloor space cannot enter
9.1.3.4 Garages and openings to garages
the cavity. This is important, as moisture levels in
Refer to Figure 65 and Table 18 for overall level subfloor air can be high.
Amend 5
Aug 2011 change requirements.
COMMENT:
This paragraph does not apply to garages that are
detached outbuildings.
COMMENT:
Methods for achieving the required step may include:
• A 50 mm difference in finished ground level adjacent
to the opening, or
• A raised threshold at the opening, or
• Concrete nibs at the opening.
9.1.4 Barriers to airflow
b) Provision to drain water away from the
This Acceptable Solution requires external walls
threshold of the opening
to have barriers to airflow, in the form of:
c) Rigid wall underlays, to Table 23, where
a) Interior linings with all joints stopped for
external garage walls are unlined
wind zones up to Very High, or
d) linings to garage walls adjoining habitable
b) Rigid underlays (and drained cavities) for
spaces
buildings in Extra High wind zones – refer
e) weather resisting garage doors to Paragraph 9.1.7.2
Amend 5
f) window and door details (where c) Where walls are not lined, such as attic
Aug 2011 included) to Paragraphs 9.2 to 9.9. spaces at gable ends, an air barrier
complying with Table 23, fixed to framing
prior to fixing cladding or cavity battens
Amend 5
9.1.3.5 Bottom of wall claddings for timber
Aug 2011 floor framing d) For attached garages, underlays to
Amend 5
Paragraph 9.1.3.4. Aug 2011
Suspended timber floors shall meet the
Amend 5
Aug 2011 requirements of NZS 3604. Clearances from .
paved and unpaved surfaces to the wall
framing shall be in accordance with NZS 3604,
and Table 18.
98 1 August 2011 D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G
A c c e p ta b le So lu tio n E 2 /AS1 EXTERNAL MOISTURE
COMMENT: COMMENT:
The primary function of air barriers and air seals is to Some sealants can react with bitumen based flashing
moderate airflows at junctions and inside the wall cavity. tape, preventing full curing of the sealant. Where necessary,
consult sealant manufacturers for application requirements. Amend 5
Aug 2011
Airflows in certain weather conditions encourage
Backing rods are used for sealant and for self-expanding
significant amounts of water to move along their path, polyurethane foam as there is a danger foam will expand
and it is therefore important to manage airflow in cavity to the outside of the wall and form a moisture bridge to
walls with barriers and air seals. the interior.
In the absence of internal linings, an air barrier is For further information refer to ASTM C1330 for backing
required to support wind pressures at locations such as rod material performance.
gable ends and unlined garage spaces. Air pressure drop
is not always across the internal lining, indicating the 9.1.7 Wall underlay
Amend 5
wall underlay acts as an air barrier as well. 9.1.7.1 Flexible wall underlays shall be in Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
Figure 66: Cavity base closer/vermin proofing
External air pressures in higher wind zones can transfer Paragraph 9.1.8.2
to interior linings, and exceed recommended loadings
prescribed by some lining manufacturers. Rigid
underlays will protect linings from undue air pressure
loadings, and help ensure cavity depths are maintained
Amend 5 for the proper functioning of the drained cavity.
Aug 2011
COMMENT:
Cavities manage occasional ingress of water past the
cladding, but should not act as gutters or drains.
9.1.8.1 Limitations
This Acceptable Solution is limited to systems
Amend 5
where: Aug 2011
c) Be fixed, by the cladding fixings, through Window penetrations through cavities shall
Amend 5
Aug 2011 the wall underlay into the framing, meet the requirements of Paragraph 9.2
to Paragraph 9.9.
d) If timber, comply with B2/AS1,
9.1.9.2 Other cavity penetrations
e) If polystyrene, comply with Paragraph 9.9.3.1,
Where penetrations of the wall cladding are
and be protected from any incompatible
wider than the cavity batten spacing,
vapours from timber treatment.
allowance shall be made for air flow between
Cavity battens and/or cavity spacers that adjacent cavities by leaving a minimum gap of
meet E2/VM1 Class 1 testing and B2/AS1, 10 mm between the bottom of the vertical
permit air circulation are allowed. The Class 1 cavity batten and the flashing to the opening.
test must include a horizontal cladding joint 9.1.9.3 Pipes and service penetrations
supported on a cavity spacer batten of a
Amend 5 Pipes and service penetrations shall be made
Aug 2011 proposed type.
weathertight by using methods shown in
Jamb battens shall: Figures 68 and 69. Flashing tape complying with Amend 5
f) be nominal 20 mm (between limits of 18 mm Paragraph 4.3.11, and sealant complying with: Aug 2011
Amend 5
Aug 2011
Amend 5
Aug 2011
COMMENT:
Where possible, pipe penetrations, meterboxes and
Amend 5
Aug 2011 similar penetrations should be located in sheltered areas
of the building, such as a porch, or be installed behind a
weatherproof glazed panel.
Figure 69: General meterbox and similar Figure 70: General inter-storey junction
penetrations Paragraphs 4.6.1.7, 9.1.9.4,
Paragraphs 9.1.9.3, 9.6.8.5 and 9.6.9.6 Figure 16
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
Figure 71: General sealing of head flashing
Sloped heads require specifically designed kick-out
Paragraphs 9.1.7, 9.1.10.3 and 9.1.10.4
flashings at bottom edges of head flashings.
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 72A: General window and door opening for direct fixed
Paragraphs 9.1.5, 9.1.10.2, Figures 81, 82, 83, 84, 90, 95 and 115
Errata 2
Dec 2011
Amend 5
Aug 2011
Figure 72B: General window and door opening with drainage cavity
Paragraphs 9.1.5, 9.1.9.3, 9.1.10.2, Figures 73C, 76, 85, 86, 91, 99, 116 and 128
Errata 2
Dec 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
b) Concrete brick or block.
Refer to Paragraph 1.5 for qualification of installers
COMMENT:
Natural stone bricks or blocks may be suitable. However, 9.2.4 Flashings
they are not part of this Acceptable Solution. Refer to 1) Sill and head flashings shall be as described
the manufacturer’s recommendations for specific
in Paragraph 4.3 and be either:
design information.
9.2.3 Installation
Masonry veneer construction shall be as Figure 73A: Vertical control joint
shown in Figure 73B, and have: Paragraph 9.2.8
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Errata 2
Dec 2011
Errata 2
Dec 2011
Amend 5
Aug 2011
Errata 2
Dec 2011
Errata 2
Dec 2011
Errata 2
Dec 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Errata 2
Dec 2011
Errata 2
Dec 2011
Errata 2
Dec 2011
Errata 2
Dec 2011
Amend 5
Aug 2011
b) For rebates above ground floor level: d) The cavity shall be ventilated to the outside
i) 1.0 mm butyl rubber or bituminous at the top of walls by either similar vents
Errata 2
sheet, or as at the bottom, or a continuous 5 mm Dec 2011
ii) 0.25 mm polythene or polyethylene minimum gap between the top course and
damp-proof membrane. soffit board, with a cover bead to outside
Errata 2
that maintains a minimum 2 mm gap to Dec 2011
5) Lap joints in flashings minimum of 150 mm.
masonry – refer to Figure 73E(l).
6) Dimension rebates to accommodate the
e) The cavity shall be vented under openings
required cavity width in Paragraph 9.2.6
exceeding 2.4 metres wide through gaps
and the thickness of the veneer so that the
in perpends positioned at 1/3 points along
veneer is supported within the tolerances
Amend 5 the opening except at opening ends. Where
Aug 2011 outlined in Figures 73D and E.
these vent openings are used, protect from
water entry using cantilevered sill bricks, as
shown in Figure 73C (f).
f) The cavity shall be sealed off from the floor
Amend 5
and roof space. Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Errata 2
Table 18A: Specification of maximum tie spacings for type B (4) veneer ties Dec 2011
Paragraph 9.2.7
COMMENT:
9.2.7 Wall ties
Variations in cavity width will require compensating Masonry veneer shall be attached to wall framing
adjustments to the length of masonry tie used. by wall ties. Wall ties and their spacings and
embedment shall be in accordance with the
requirements of NZS 4210 and Tables 18A, 18B
and 18C. Screw fixings shall be minimum
12 gauge, 35 mm long hex washer face,
galvanised or stainless steel to suit the ties
required under Table 18C.
Amend 5
Aug 2011
9.2.7.1 Wall ties and screws shall be Control joints shall be formed as shown
determined by the durability zone outlined in Figure 73A and comprise:
in NZS 3604 and as outlined in Table 18C. a) A backer rod of compressible foam, and
b) Sealant in compliance with:
i) Type F, Class 20LM or 25LM of ISO
11600, or
ii) low modulus Type II Class A of Federal
Specification TT-S-00230C.
Table 18C: Corrosion protection to masonry
wall ties 9.2.9 Openings in masonry veneer
Paragraph 9.2.7
Openings with masonry veneer above shall
316, 316L, 470 g/m2 be spanned by steel angle lintels.
or 304 galvanising
stainless steel on mild steel Openings in masonry veneer for meter boxes
Zone B Yes Yes less than 500 mm wide may be installed
Zone C Yes Yes without lintel bars or head flashings provided
Errata 2
Zones D and E Yes
– the meter box is sealed to wall underlay with
Dec 2011
flashing tape to Paragraph 4.3.11.
Separate steel meter boxes from direct
contact with masonry veneer or mortar with
9.2.8 Control joints flashing tape to Paragraph 4.3.11.
Control joints in clay brick masonry veneer a) Be protected against corrosion as in Table 18D
are not required, unless specified by the brick and to exposure zones outlined in NZS 3604.
manufacturer. b) Have a minimum seating into adjacent
9.2.8.2 Concrete bricks veneer of:
Longitudinal shrinkage stresses in concrete i) 100 mm for spans up to, and including
masonry veneer shall be controlled by 2 m,
providing vertical control joints at not more ii) 200 mm for spans over 2 m.
than 6 m centres. c) Be sized in accordance with Table 18E.
Vertical control joints shall be located:
(a) Within 600 mm of T joints Table 18D: Corrosion protection to lintels
Paragraph 9.2.9, Table 18E
(b) Within 600 mm of L shaped corners
or by restricting the spacing to the next 316 or 316L or 600 g/m2
control joint to 3.2 m maximum 304(2) stainless galvanising on
steel or mild steel(1) or
(c) At changes in wall height, exceeding
600 g/m2 300 g/m2
600 mm galvanising on galvanising on
Amend 5 mild steel plus mild steel plus
Aug 2011 (d) At changes in wall thickness.
duplex coating(1) Duplex coating(1)
Zone B Yes Yes
Zone C Yes Yes
Zone D Yes
1) To AS/NZS 2699.3
2) 304 stainless steel will exhibit greater levels
of surface rusting than 316 stainless steel,
Amend 5
especially where not exposed to rain washing. Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
70 90
Maximum height of veneer supported (mm)
350 700 2000 350 700 2000
0.800 60 x 60 x 6 L 60 x 60 x 6 L 60 x 60 x 6 L 60 x 80 x 6 L 60 x 80 x 6 L 80 x 80 x 6 L
2.000 60 x 60 x 6 L 60 x 60 x 6 L 60 x 60 x 6 L 60 x 80 x 6 L 60 x 80 x 6 L 80 x 80 x 6 L
2.500 60 x 60 x 6 L 80 x 80 x 6 L 80 x 80 x 6 L 80 x 80 x 6 L 80 x 80 x 6 L 80 x 80 x 6 L
3.000 80 x 80 x 6 L 80 x 80 x 6 L 125 x 75 x 6 L 80 x 80 x 6 L 80 x 80 x 8 L 90 x 90 x 10 L
3.500 80 x 80 x 6 L 80 x 80 x 6 L 125 x 75 x 6 L 80 x 80 x 8 L 90 x 90 x 10 L 125 x 75 x 10 L
4.000 80 x 80 x 8 L 125 x 75 x 6 L 125 x 75 x 10 L 80 x 80 x 10 L 125 x 75 x 6 L 150 x 90 x 10 L
4.500 125 x 75 x 6 L 125 x 75 x 10 L _ 125 x 75 x 6 L 125 x 75 x 10 L _
4.800 125 x 75 x 6 L 125 x 75 x 10 L _ 125 x 75 x 6 L 125 x 75 x 10 L _
Amend 5
Aug 2011 9.2.10 Windows and doors
The openings in wall framing for windows and
Amend 5
Aug 2011 doors shall have flexible flashing tape applied,
in accordance with Paragraph 9.1.5.
Air seals shall be provided in accordance with
Paragraph 9.1.6.
Window flashings shall be installed in
accordance with Paragraph 9.2.4 and Figures
73C and 73D(h).
Amend 5
Aug 2011 9.2.11 Secondary cladding
Where a secondary cladding is used with the
masonry veneer, and is direct fixed to framing
above windows or at gable ends, this shall be
fully sealed on:
a) The face of the cladding,
b) All edges of the cladding, and
c) A 75 mm minimum perimeter strip on the
rear of the cladding.
Amend 5
Aug 2011
9.3 Stucco
Errata 2
9.3.1 Limitations Dec 2011
b) Solid plaster cladding with a rigid backing 9.3.3.1 All stucco cladding shall have
and a drained cavity. Refer to Figure 74 wall underlay as specified in Table 23 and Amend 5
Aug 2011
Paragraphs 9.1.5–9.1.7, and shall be:
9.3.2 Structure
a) Fixed to the framing as specified in Table 23,
The timber framing of external walls
and
supporting stucco wall claddings shall comply
with NZS 3604 and NZS 4251. The cladding b) Provided as an overlay to rigid backings
system shall be attached to the wall framing. to provide a slip layer that permits the
independent movement of plaster and
The framing for buildings using stucco exterior
backing.
cladding systems shall be supported on a:
9.3.3.2 Have plaster backing installed as in
a) Concrete slab-on-ground, or
Paragraphs 9.3.5 and 9.3.6.
b) Continuous reinforced concrete foundation
9.3.3.3 Have metal lath reinforcements for
wall, or
stucco plaster attached through the plaster
Amend 5
c) Reinforced concrete masonry foundation backing as described in Table 24. Aug 2011
wall.
9.3.4 Installation
COMMENT:
Refer to Paragraph 1.5 for qualification of installers.
Amends
2 and 5
Amend 5
Amend 5 Aug 2011
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
The wall underlay shall be in accordance with tested and rated systems.
Table 23, and as described in Paragraphs 9.3.7 Finishes
9.1.5–9.1.7.
All stucco surfaces shall be sealed by applying
Amend 2
a minimum of a 2-coat latex exterior paint Jul 2005
COMMENT:
Stucco cladding systems cannot be assumed to be
completely weatherproof.
Amend 2
Jul 2005
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
fixed or fixed over a drained cavity, according to the framing in accordance with Table 24.
to the risk categories as shown in Table 3.
9.4.2 Materials
Timber weatherboard cladding shall include
the following features:
a) Wall underlay complying with Table 23 and
Amend 5
Aug 2011 Paragraphs 9.1.5–9.1.7, and
b) Timber selection and treatment of
weatherboards in accordance with
NZS 3602.
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
weatherboards, corner boxes with: at all internal corners as shown in Figure 79.
i) scribers for bevel-back weatherboards,
as shown in Figure 78, or
ii) plugs or scribers for rusticated
weatherboards, as shown in Figure 78,
b) For bevel-back weatherboards:
i) mitred joints with back flashing as
shown in Figure 78, or
ii) mitred joints with corrosion-resistant
soakers – refer to Paragraphs 4.3.2
to 4.3.6 and Figure 77.
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
ii) have weather grooves to boards and the weatherboards at all internal corners.
battens aligned.
Amend 5
Aug 2011 9.4.6 Windows and doors in direct fixed 9.4.7 Windows and doors in cavity walls
weatherboards Window and door details for bevel-back
Amend 5
Aug 2011
Amend 5
Aug 2011 Window and door details for: weatherboards on a drained cavity shall be as
a) Direct fixed bevel-back weatherboards are shown in Figure 85.
Amend 5
shown in Figure 81, Window and door details for rusticated Aug 2011
b) Direct fixed rusticated weatherboards are weatherboards on a drained cavity are shown
shown in Figure 82, in Figure 86.
Amend 5
c) Vertical shiplap weatherboards are shown in Door sill details are as shown in Figure 17C. Aug 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 81: Windows and doors for direct fixed bevel-back weatherboards
Paragraph 9.4.6
Amend 2
Jul 2005
Amend 5
Aug 2011
Figure 82: Windows and doors for direct fixed rusticated weatherboards
Paragraph 9.4.6
Amend 2
Jul 2005
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 83: Windows and doors for direct fixed vertical shiplap weatherboards
Paragraph 9.4.6
Amend 2
Jul 2005
Amend 5
Aug 2011
Figure 84: Windows and doors for direct fixed board and batten weatherboards
Paragraph 9.4.6
Amend 2
Jul 2005
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Amend 5 Jul 2005
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
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COMMENT:
The minimum durability period for protective coatings
is 5 years. Improvement in durability and stability of
weatherboards can be achieved by priming all surfaces
Amend 5
Aug 2011 including backs of boards.
Based on the risk score for an external wall, Horizontal laps shall be a minimum of 30 mm.
calculated as per Paragraph 3.1, the fibre Joints shall be:
cement weatherboard cladding may require
a) Positioned between studs,
the inclusion of a drained cavity.
b) Staggered at a minimum of 600 mm from
9.5.1 Limitations
joints in the adjacent boards, and
This Acceptable Solution is limited to flat fibre
c) Weatherproofed by:
cement weatherboards, with a minimum
i) uPVC H jointers as shown in Figure 87, or
thickness of 7.5 mm.
ii) hidden soakers as shown in Figure 87,
9.5.2 Material performance with sealant used between ends of
Fibre cement weatherboards shall comply boards complying with:
with AS/NZS 2908: Part 2. a. Type F, Class 20LM or 25LM of
ISO 11600, or
9.5.3 Installation
b. low modulus Type II Class A of
A wall underlay, as specified in Table 23 and Federal Specification TT-S-00230C.
Amend 5
Aug 2011 Paragraphs 9.1.5–9.1.7, shall be installed
behind fibre cement weatherboard claddings.
COMMENT:
Amend 5
Refer to Paragraph 1.5 for qualification of installers.
Aug 2011
Amend 5
Figure 87: Joints in fibre cement weatherboards Aug 2011
Paragraph 9.5.3.2
Amend 2
Jul 2005
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 90: Windows and doors in fibre cement direct fixed weatherboards
Paragraph 9.5.4.1
Amend 5
Amend 2
Aug 2011
Jul 2005
Amend 5
Aug 2011 Amend 2
Jul 2005
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Amend 2
Jul 2005
9.6 Profiled Metal Wall Cladding 9.6.3.2 Steel
Materials for the manufacture of profiled steel
Horizontal profiled metal wall cladding shall
cladding shall:
be fixed over a drained cavity as described in
Paragraph 9.1.8. a) Have a BMT of 0.4 mm minimum,
Vertical profiled metal wall cladding shall be b) Be grade G550, or G300 for curved and
direct fixed to framing over a roof underlay. crimped cladding
Refer to Table 3: Suitable wall claddings. c) Be selected for corrosion protection Amend 2
Jul 2005
according to the intended exposure zone as
9.6.1 Limitations
shown in Table 20.
This Acceptable Solution is limited to
corrugated or trapezoidal metal wall cladding
Amend 2
with the profiles, as shown in Figure 38, and Jul 2005
applied as outlined in Table 3.
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
9.6.2 General
Amend 5
Amend 2 Aug 2011
Jul 2005 9.6.3.3 Aluminium
COMMENT:
Aluminium for the manufacture of profiled
Refer to Paragraph 1.5 for qualification of installers.
aluminium wall cladding shall comply with
AS/NZS 1734, and be:
Amends
2 and 5 a) A base metal thickness (BMT) of a
9.6.3 Materials minimum of 0.7 mm,
9.6.3.1 Choice of metal b) Minimum 5000 series.
The metal cladding shall be selected according Amend 2
Jul 2005
to the exposure conditions in Table 20 as For pre-painted aluminium, a factory-applied
defined in: finish complying with AS/NZS 2728 shall be
Amend 5
Aug 2011 a) NZS 3604, or applied.
b) AS/NZS 2728. 9.6.4 Maintenance
Refer to Paragraph 2.5.
Amend 5
Aug 2011
COMMENT:
The exposure zone in which a building is located can
affect the durability of flashings.
Amend 5 e) Include neoprene (having a carbon black properties listed for roof underlay in Table 23.
Aug 2011
content of 15% or less by weight) or EPDM For copper-based treated framing or underlay
Amend 2 Amend 5
Jul 2005 sealing washers as shown in Figure 39, and refer to Paragraph 9.6.9.2. Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
9.6.8.5 Vertical profile: penetrations 9.6.8.6 Vertical profile: windows and doors
Amend 5
Pipe penetrations shall be as per Figure 53. Windows and doors in vertical profiled metal Aug 2011
The heads of larger penetrations shall be claddings shall be flashed as shown in Figure
flashed in similar fashion to Figure 69, with 95 and Figure 100.
head flashings adjusted to suit the profile
Amend 5
Aug 2011 and other flashings as per window and door
details in relevant paragraphs.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
141
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Amend 5 Jul 2005
Aug 2011
copper azole or ACQ), appropriate separation separation of 5 mm, against sides of the
between the back of the cladding and the exposed flashing corner, and
cavity batten shall be provided. c) Use profiled compressible foam to seal
Examples of suitable separation are: between the flashing underlap and
a) An additional layer of paper-based underlay, underside of cladding.
Amends complying with Table 23, over cavity battens,
2 and 5
b) Strips of paper-based underlay complying
with Table 23 on the face of cavity battens,
Amend 2
Jul 2005
c) Pre-priming cavity battens.
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
9.6.9.7 Horizontal profile: windows and doors Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
Figure 99: Windows and doors for horizontal profiled metal on cavity
Paragraph 9.6.9.7
Amend 2
Amend 5 Jul 2005
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
Jul 2005 Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
147
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
9.7.2 Material and installation –
Aug 2011 both systems
Fibre cement shall comply with
AS/NZS 2908: Part 2.
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
149
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 105: Vertical timber batten joints for fibre cement sheet
Paragraph 9.7.3
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
151
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
9.7.3.1 Paint finish iii) where a topcoat of paint over the finish
For jointed systems, all sheet edges shall be is required to provide weather protection,
sealed prior to fixing. Fibre cement shall be is a latex exterior paint system complying
finished with a latex exterior paint system with any of Parts 7, 8, 9 or 10 of AS 3730.
complying with any of Parts 7, 8, 9 or 10 b) Joints shall be positioned so that they:
of AS 3730. i) do not occur at corners of window or
9.7.4 Flush-finished systems door openings or at changes in the
Flush-finished systems shall be constructed height of a wall
over a drained cavity outlined in Paragraph 9.1.8. ii) are a minimum of 200 mm on either side
of the jamb-line of an opening
a) Flush-finished joints shall be finished with
iii) detailed as shown in Figure 110.
a textured finish system that:
c) External corners shall use uPVC corner
i) complies with BRANZ EM 4, when
reinforcement beneath tape and finishing
tested with the specific fibre cement
compound as shown in Figure 113.
substrate and jointing system used for
the cladding d) Internal corners shall use a sealant-filled
ii) has all components approved by the joint over compressible foam tape as
Amend 5
Aug 2011 supplier of the jointing and finish system shown in Figure 111 b) with polyethylene
Amend 5
bond breaker tape behind joint. Aug 2011
Vertical control joints shall be located as a) Metal, butyl or EPDM to Paragraph 6.3, or,
shown in Table 19, and: b) Flush-finished fibre cement to Paragraph
a) May occur at the edge of window or door 9.7.7.1 and Figure 117.
openings,
b) Shall extend the full height of the wall, Figure 110: Flush-finished joints for fibre
including where there is a horizontal joint cement sheet
and a vertical control joint on the wall Paragraph 9.7.4
9.7.4.2 Finishes
Finish colour shall have a reflectance of 40%
or more, as outlined in Paragraph 2.4.
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 111: Vertical movement control joint for flush-finished fibre cement sheet
Paragraph 9.7.4.1
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Figure 115: Windows and doors for direct fixed fibre cement sheet
Paragraph 9.7.6
Amend 5 Amend 2
Aug 2011 Jul 2005
Figure 116: Windows and doors for fibre cement sheet and flush-finished fibre cement on cavity
Paragraph 9.7.6
Amend 2
Jul 2005
Amend 5
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 2
9.7.7.1 Flush-finished topped balustrades Jul 2005
Errata 2
Dec 2011
Amend 5
Aug 2011
COMMENT:
Alternatively, a decorative moulding may be formed
from the coating by using mesh and plaster.
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011 9.8.2 Materials
Amend 5
Aug 2011
Batten-jointed panels shall have weather-
grooved timber battens as shown in Figure 119.
Plywood panels shall be:
a) Manufactured to AS/NZS 2269, grade CD,
Figure 120 deleted
b) A minimum of 5 ply,
c) A minimum of 12 mm in thickness, and
d) Treated as required by NZS 3602.
Amend 5
Aug 2011
Amend 5
Aug 2011
Internal corners shall be as shown in Figure shown for fibre cement sheet cladding –
123 and have: refer to Figure 115.
a) Flashings and timber battens for direct fix 9.8.8.2 Windows and doors: with cavity
Amend 5
Amend 5
Aug 2011 b) Timber battens for cavity fix. Windows and doors shall be detailed as Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
Plywood for cladding, treated to H3, does not require
Amend 5
Aug 2011 painting.
Amends While H3 plywood can be left unpainted, it is likely to
2 and 5
develop checking and mould growth on the surface.
Amend 5
Aug 2011 Plywood used as bracing requires painting and regular
maintenance of the paint finish to ensure the 50-year
durability is achieved.
Amend 5
Aug 2011
Fixings shall:
c) A polymer-modified cement or polymer-
based finishing plaster, and a latex exterior a) Be spaced as shown in Table 24,
paint system complying with any of Parts 7, b) Penetrate the framing by 30 mm minimum,
8, 9 or 10 of AS 3730,
c) Comply with AS/NZS 4680, and
d) A range of head, sill, jamb, corner and base
d) Be either:
mouldings suitable for exterior use, and
i) hot-dipped galvanized springhead nails
e) A flexible polymeric neutral cure sealant that: with a 22 mm top, or
ii) hot-dipped galvanized flat head nails
used in conjunction with a 22 mm
minimum diameter plastic washer.
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
COMMENT:
The system supplier may require control joints at
closer spacings.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
165
EXTERNAL MOISTURE A cceptable Solution E2/A S 1
9.9.7 EIFS/floor slab junction Figure 125: Bottom of cladding for EIFS
The bottom of the EIFS cladding shall be as Paragraph 9.9.7
shown in Figure 125.
9.9.8 Pipes and service penetrations
All pipes and service penetrations through the
EIFS shall be made weatherproof, by either:
a) A flange penetrating the EIFS as a sleeve
and sealed into the EIFS system as shown
in Figure 126, or
b) A face-fitted flange at EIFS surface, sealed
with a neutral cure sealant complying with:
i) Type F, Class 20LM or 25LM of
ISO 11600, or
ii) low modulus Type II Class A of Federal
Specification TT-S-00230C.
Amend 5
Aug 2011
Amend 5
Aug 2011
Amend 2
Jul 2005
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Amend 2
Jul 2005
Amend 5
Aug 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
Aug 2011
Amend 5
Aug 2011
a) For timber framing at the time of installing Measurement shall be made in accordance
interior linings, the maximum acceptable with BRANZ Bulletin 330 Thin Flooring
moisture content shall be the lesser of: Materials using hygrometers calibrated to
ASTM E 104 – 2002 Standard practice for
i) 20% for insulated buildings, 24% for
maintaining constant relative humidity by
non-insulated buildings, or
means of aqueous solutions.
ii) as specified in NZS 3602,
b) For timber weatherboards and exterior
joinery, 20% at the time of painting,
c) For reconstituted wood products, 18%
at all times, and
d) For concrete floors, sufficiently dry to give
a relative humidity reading of less than 75%
at the time of laying fixed floor coverings.
COMMENT:
Some manufacturers of timber or other wall or floor
components may recommend lower moisture contents
for their products.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Note:
1) Refer to manufacturer’s information for maintenance requirements in Exposed and Sheltered locations.
2) The term “hidden” means concealed behind another element such that no part is visible. Hidden elements
require a 50 year durability under the NZBC. The term “exposed” means having surfaces exposed to rain washing.
The term ‘sheltered’ means being visible, but not rain washed. For diagrammatic outline, refer NZS 3604
Figure 4.3(a). Exposed and sheltered elements require a 15 year durability. Where an element can be categorised
as both ‘sheltered’ and ‘exposed’, the ‘sheltered’ condition will apply.
3) AS/NZS 2728 lists atmospheric classes derived from ISO 9223 for Australia and New Zealand, determined by
exposure to wind-driven sea-spray. NZS 3604 references atmospheric classes B (Low), C (Medium) and D (High).
E2/AS1 references atmospheric zones B,C,D,E. For the purposes of cladding selection, Zone E (Severe marine
classified as breaking surf beach fronts) has been included. Designers must consult metal supplier’s information for
specific durability requirements of sites in Zone E.
4) The geographic limits of atmospheric classes in NZS 3604 and AS/NZS 2728 may vary. Table 20 uses the limits
outlined in NZS 3604.
5) Includes fixings protected by putty and an exterior paint system of primer, undercoat and two top coats of paint.
6) Microclimates based on evidence from adjacent structures of corrosion caused by industrial or geothermal
atmospheres are outside the scope of this Acceptable Solution.
7) Refer to Tables 21 and 22 for compatibility of fixings with metal claddings.
8) Roof only. Coated steel wall claddings must be considered as ‘sheltered’.
9) Hidden steel coated elements in ventilated cavities in zones D and E (exposure to salt air) must be considered
as ‘sheltered’
10) The use of stainless steel fixings is not recommended by steel manufacturers for use with coated steel in severe
Amend 5 marine and industrial environments, as they are considered to cause deterioration.
Aug 2011
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
( combinations), (unpainted)
Zinc-aluminium-magneisum
Zinc-aluminium-magnesium
Clay bricks (cement mortar)
Stainless steel
Copper/brass
Plastics
Cedar
Glass
Zinc
Amend 6
Feb 2014
Aluminium, anodised or ✓ ✓ ✓ ✘ ✓ ✘ ✘ ✘ ✓ ✘ ✘ ✓ ✓ ✘ ✓ B ✓ ✓ ✓ ✓ ✓
mill-finish
Aluminium, coated (1) ✓ ✓ ✓ B ✓ ✘ ✘ ✘ ✓ ✘ ✘ ✓ ✓ B ✓ B ✓ ✓ ✓ ✓ ✓
Butyl rubber & EDPM ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
CCA-treated timber (2) ✘ B ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ B ✘ ✘ B ✘
Cedar ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
Cement plaster ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✘
(uncoated)
Ceramic tiles ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘
(cement grout)
Clay bricks ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘
(cement mortar)
Concrete old ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
(unpainted)
Concrete green ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✓ ✓ ✘ ✘ ✘ ✘ ✘
(unpainted)
Copper/brass ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ B ✓ B ✘ ✘ ✘ ✘ ✘
Glass ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
Glazed roof tiles ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
Lead (including ✘ B ✓ ✓ ✓ ✘ ✓ ✓ ✓ ✘ B ✓ ✓ ✓ ✓ B B B B B ✘
lead-edged) unpainted
Plastics ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
Stainless steel B B ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ B ✓ ✓ B ✓ ✓ B ✘ ✘ B B
Steel, galvanised ✓ ✓ ✓ B ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓ B ✓ B ✓ ✓ ✓ ✓ ✓
coil-coated
Steel, galvanized ✓ ✓ ✓ ✘ ✘ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓ B ✓ ✘ ✓ ✓ ✓ ✓ ✓
(unpainted)
Zinc ✓ ✓ ✓ ✘ ✘ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓ B ✓ ✘ ✓ ✓ ✓ ✓ ✓
Zinc-aluminium- ✓ ✓ ✓ B ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓ B ✓ B ✓ ✓ ✓ ✓ ✓
magenesium
(combinations),
coated (1)
Zinc-aluminium- ✓ ✓ ✓ ✘ ✘ ✘ ✘ ✘ ✓ ✘ ✘ ✓ ✓ ✘ ✓ B ✓ ✓ ✓ ✓ ✓
magnesium
Amend 6 (combinations)
Feb 2014
(unpainted)
LEGEND:
✓ Materials satisfactory in contact.
✘ Contact between materials is not permitted. Minimum gap of 5 mm is required to prevent moisture bridging.
B Avoid contact in sea-spray zone or corrosion zone D.
NOTES:
(1) Coated – includes factory-painted, coil-coated and powder-coated. Amend 2
(2) Includes copper azole and copper quaternary salts. Jul 2005
( combinations), (unpainted)
Zinc-aluminium-magneisum
Zinc-aluminium-magnesium
Clay bricks (cement mortar)
Stainless steel
Copper/brass
Material that
Plastics
Cedar
Glass
water flows
Zinc
from Amend 6
Feb 2014
Aluminium, anodised or ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
mill-finish
Aluminium, coated (1) ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
Butyl rubber & EDPM ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
CCA-treated timber (2) ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✘ ✘ ✘
Cedar ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
Cement plaster ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ A ✓ ✘ ✓ ✓ ✓ ✘ ✘ ✓ ✘
(uncoated)
Ceramic tiles ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ A ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
(cement grout)
Clay bricks ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ A ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✘
(cement mortar)
Concrete old ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ A ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
(unpainted)
Concrete green ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ A ✓ ✘ ✓ ✓ ✘ ✘ ✘ ✘ ✘
(unpainted)
Copper/brass ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✘ ✘ ✘
Glass ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
Glazed roof tiles ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
Lead (including ✘ ✘ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘
lead-edged) unpainted
Plastics ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
Stainless steel ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
Steel, galvanised ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
coil-coated
Steel, galvanized ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
(unpainted)
Zinc ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓
Zinc-aluminium- ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
magenesium
(combinations),
coated (1)
Zinc-aluminium- ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✓ ✘ ✘ ✓ ✓
magnesium
Amend 6 (combinations)
Feb 2014
(unpainted)
LEGEND:
✓ Materials satisfactory with water run-off as indicated.
✘ Water run-off is not permitted as indicated.
A Etching or staining of glass may occur with run-off.
NOTES:
(1) Coated – includes factory-painted, coil-coated and powder-coated.
Amend 2
Jul 2005
(2) Includes copper azole and copper quaternary salts.
Errata 2
Dec 2011 Table 23: Properties of roof underlays and wall underlays
Paragraphs 6.2, 8.1.5, 8.2.3, 8.3.6, 8.4.7, 9.1.3.4, 9.1.4, 9.1.7.1, 9.1.7.2, 9.1.8.2, 9.2.4, 9.2.5, 9.3.3,
9.3.5.1, 9.4.2, 9.4.3, 9.5.3, 9.6.8.1, 9.6.9.1, 9.6.9.2, 9.7.2.1, 9.8.3 and 9.9.4
NOTE:
1) Metal roofs and direct-fixed metal wall claddings require paper-based underlays
2) Excluding synthetic underlays
3) Use paper based underlays where directly behind (in contact with) profiled metal wall cladding
4) Excludes profiled metal wall cladding
5) Plywood to be treated in accordance with NZS 3602
6) Bitumen based products shall not be used in direct contact with LOSP-treated plywood
Amend 5 7) Applies only to air barriers used with non-absorbent claddings.
Aug 2011
Amends
2 and 5
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EXTERNAL MOISTURE A cceptable Solution E2/A S 1
Amend 5
LEGEND: Aug 2011
Amend 5
Aug 2011
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179
180
A c c e p ta b le So lu tio n E 2 /AS2 EXTERNAL MOISTURE
100 min
600
max Permanent paving D.P.M. (refer Clause 4.8.5)
on sand blinding
on selected hardfill
Finished exterior ground level (refer Clause 4.8.4)
Varies
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 May 2008
181
EXTERNAL MOISTURE A cceptable Solution E2/A S 2
Clause 5.1.8 Add new Clause: Clause 5.12 Add new Clause and Figure:
5.1.8 5.12 Soffit to wall junction
The external surface of earth walls must be The junction between the soffit and the
finished in accordance with Clauses 2.2.3.5, earth wall must be constructed as shown
2.2.4.2 and 2.2.4.3 of NZS 4298. The external in Figure 5.11.
surface of earth walls must be free from Figure 5.11 – Soffit to wall junction
features, such as horizontal protrusions,
that could cause water to become trapped
or directed towards the inside of the building.
C5.1.8
Water must be able to flow downwards and off the
external surface of earth walls.
Note:
Gable to be detailed in a similar manner
Roof framing constructed to NZS 3604
Selected
timber trim Earth wall
Timber fascia or
beam as required
& gutter system
Eave soffit D.P.C.
25 mm min or verandah lining (See Clause 2.1.8.5)
Note:
Roof framing constructed to NZS 3604
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 May 2008
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EXTERNAL MOISTURE A cceptable Solution E2/A S 2
Gable frame
To suit
10 mm stop-end
55 mm min
Timber plate on D.P.C. 5 mm min
(See Clause 2.1.8.5) @ 15˚min
Reinforced concrete lintel 30 + 20 mm min*
Lining on ex 100x50
framing @ 600 crs 15 mm min Run cladding into jamb
rebate each side of opening
Fix head trim after all shrinkage Flashing material as defined in Acceptable Solution E2/AS1
has taken place
Timber facing
INTERIOR EXTERIOR
Line of jamb rebate
10 mm stop-end
55 mm min
Timber plate on D.P.C.
(See Clause 2.1.8.5) 10 + *20 mm min
5 mm min
Reinforced concrete lintel
@15˚min
(Refer figure 8.4)
15˚ min slope,
Ex 25mm timber take flashing full width
boxing, or laminated ply into jamb rebate each
to curve as required 6x6 drip groove end.
FLASHING DIMENSIONS
Varies according to lintel span Run cladding into
jamb rebate each
side of opening
Lining on ex 100x50
framing @ 600 crs
Building wrap as required by Acceptable Solution E2/AS1
Tight fitting closed cell
compressible foam rod or tube Lap building wrap
or hemp rope over headflashing
Fix head trim after all shrinkage 50 mm min cladding lap over flashing
has taken place
5 mm min clearance between
cladding and flashing
*20 mm
* Note: 20 mm shrinkage gap may 10 mm min flashing lap to flange
* 20 mm
be reduced by up to 10 mm if
justified by results of mortar and
wall material shrinkage tests to Flashing material as defined
NZS 4298, Appendix F in Acceptable Solution E2/AS1
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 May 2008
185
EXTERNAL MOISTURE A cceptable Solution E2/A S 2
INTERIOR EXTERIOR
When eaves are less than or equal to 600
insert tight fitting, closed cell & moisture
resistant, compressible foam rod or tube at
outer edge of lintel between lintel & earth
wall at all points of contact.
D.P.C. (See Clause 2.1.8.5)
Head flashing
full width of opening.
Timber lintel/bond beam
Fix up into sawn slot
(solid or boxed) as required
aligned with jamb rebate.
(refer figure 8.1)
To suit
Tight fitting closed cell 10 mm Ø
compressible foam rod or tube weather groove
or hemp rope 25 mm min
5 mm min @ 15˚min
Fix timber trim after all earth wall 25 mm min 30 + *20mm min
shrinkage has taken place 20 mm min* FLASHING DIMENSIONS
* Note: 20 mm shrinkage * 20 mm 30 mm min
gap may be reduced by up
to 10 mm if justified by
Flashing material as defined
results of mortar and wall
in Acceptable Solution E2/AS1
material shrinkage tests
to NZS 4298, Appendix F
Jamb facing beyond
Pack to thickness
of timber trim (if any) Line of jamb rebate
To suit
Timber lintel/bond beam,
solid or boxed (Refer Figure 8.1) Head flashing
full width of opening. 25 mm min
Fix up into sawn slot 5 mm min @ 15˚min
Tight fitting closed cell aligned with jamb rebate. 10 + *20mm min
compressible foam rod or tube
or hemp rope 25 mm min FLASHING DIMENSIONS
*20 mm min
*20 mm
* Note: 20 mm shrinkage gap may be reduced
by up to 10 mm if justified by results
Spacer to allow head of mortar and wall material shrinkage tests
facing to move over to NZS 4298, Appendix F
jamb facings during wall
settlement
10 mm min flashing lap to flange
5 mm min
D.P.C. under packer
(See Clause 2.1.8.5) Tight fitting closed cell
compressible foam rod or tube,
INTERIOR or hemp rope
EXTERIOR
Pack to timber facing
with earth mortar
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 May 2008
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EXTERNAL MOISTURE A cceptable Solution E2/A S 2
100 mm max
25 - 75 mm
Line of jamb rebate
25 mm min rebate
Render or earth mortar
brought up to sill 2 - 10 mm gap
INTERIOR EXTERIOR
19 mm min lap
Note: requires
wide aluminium flange
INTERIOR EXTERIOR
100 mm max
Line of sill rebate
25 - 75 mm
Line of jamb rebate
Selected sill
Soaker flashing under jamb
Tight fitting closed cell or mullions that penetrate sill
Flashing material as defined in
compressible foam rod or tube, Acceptable Solution E2/AS1
or hemp rope
2 coats bituminous paint
Render or earth
mortar brought up to sill
25 mm min rebate
Earth wall
50 mm min
INTERIOR EXTERIOR
19 mm min lap
Note: requires
wide aluminium flange
Line of sill rebate Note: Fit corner and mullion flashings
Flashing material as defined
Tight fitting closed cell in Acceptable Solution E2/AS1
compressible foam rod or tube Ensure sill is positioned
or hemp rope to capture water that may
penetrate past the jamb facings
and directs it to the exterior.
D.P.C. (See Clause 2.1.8.5)
Leave 2-5 mm gap
15˚ min
Selected tiles if required
1/R10 with 50 min
cover all round
75 mm min
Precast concrete bond beam
on 3:1 sand:lime putty mortar
for unstabilised earth walls
OR 1:1:6 cement:lime:sand mortar
for stabilised earth walls 10 mm min Ø drip groove
50 mm min
OR poured insitu
Earth wall
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 May 2008
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EXTERNAL MOISTURE A cceptable Solution E2/A S 2
9.7.2
Penetrations less than 200mm wide
must meet the requirements of
NZS 4298 Clause 2.1.12 and must be
sealed all round with a tight-fitting
moisture resistant compressible closed
cell foam rod or tube that is finished
25 mm behind the wall surface, with
the resulting gap filled with:
i) for unstabilised earth construction,
a compatible unstabilised mortar
ii) for stabilised earth construction,
a compatible stabilised mortar.
Amend 5
Aug 2011 COMMENT:
C9.7.2
Generally sealants do not adhere well to earthen
surfaces with the possible exception of dense
stabilised rammed earth or pressed earth brick.
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 24 December 2011
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192
I n d e x E 2 /VM1 & AS1 /AS2 /AS3 EXTERNAL MOISTURE
D E PA R T M E N T O F B U I L D I N G A N D H O U S I N G 1 August 2011
193
194