Publication

Amendment

BRANZ works published before April 2011

All BRANZ works published before April 2011 may not fully incorporate the E2/AS1 Amendment 5 revisions.

Building Basics: Weathertightness

Download 2012 update supplement

Bulletin 457 Ventilation of enclosed subfloor spaces

Note that, while E2/AS1 only requires ventilation under suspended timber floors, BRANZ recommends as good practice that ventilation is also designed for under suspended concrete slab floors.

Bulletin 472 Waterproof
decks

Download Bulletin 472 supplement.

Bulletin 478 Rainwater collection for domestic use

Download Bulletin 478 supplement.

Bulletin 481 Timber windows

Download Bulletin 481 supplement.

Bulletin 485 Domestic on-site wastewater systems

Bulletin 495 Stair design

Figure 6(b) - The tread dimension should read 266 to give a 35º pitchline. Figure 6(c) - The pitchline for the dimensions given should be 31.85º and not 33.1º as noted.

Bulletin 498 Preparation for concrete floor slabs

Paragraph 12.0.2 of this bulletin refers to shrinkage control joints and states that: "Mesh reinforcing to the slab must stop each side of the joint." This is not correct - stopping the reinforcement each side of the joint creates a ‘free joint', not a shrinkage control joint. The mesh in a reinforced concrete slab on ground should not be cut when cutting/forming a shrinkage control joint. See Build 84 Oct/Nov 2004 p35 for more information.

Bulletin 504 NZS 4218 Calculation method

Download Bulletin 504 supplement for amendments to some calculation examples.

Bulletin 515 Measuring moisture in timber and concrete

In the first issue of this bulletin, the corrected moisture content percentages for boron-treated radiata pine given in Table 2 were wrong. The correct figures are:

The bulletin also gives an allowable moisture content of 24% for framing timber in uninsulated buildings. The figure is now 20% for all timber framing before internal linings are fixed. (Note that a lower moisture content may be required by manufacturers whose product is fixed to the timber).
The bulletin also gives an allowable moisture level for timber weatherboards and exterior joinery of 20% at the time of painting. In fact, the 20% applies at the time of installation.

This bulletin refers to NZBC clause B2 Durability, and states in paragraph 4.1.2 that: "The main roof components must be provided with a durability of not less than 50 years." Where a green roof system is designed so that it is considered moderately easy to repair/replace the waterproofing system (by removing the growing medium), it is believed that a durability that is equal to the serviceable life of the garden system, but not less than 15 years, would be appropriate for the waterproofing system. A durability of not less than 50 years would still apply to the supporting structure.
A durability of not less than 50 years is, we believe, appropriate for a waterproofing system that is difficult to access for repair and/or maintenance. Factors that would influence this include ease of access on to the roof, height of the roof and the depth of the growing medium.

Table 3 gives the wrong preservative ID number for propiconazole and tebuconazole, and no number for permethrin. The correct ID number for propiconazole and tebuconazole is 64, and the number for permethrin is 70.

Bulletin 541 Concrete floor slabs

Amendment 11 to compliance document B1/AS1 requires the use of grade 500E mesh for concrete slab-on-ground reinforcing. This change applies to slabs on ground being built to NZS 3604:2011, NZS 4229 and NZS 4299. Bars within the foundation must also be ‘E' type steel to ensure they have sufficient ductility but may be either grade 300E or grade 500E. Paragraph 4.6.1 of Bulletin 541 incorrectly asserts that all steel bars within the foundation wall must be grade 500E.

• Clause 3.2.3 of this bulletin correctly specifies the requirement for slab reinforcing to be tied to foundation wall reinforcing with R10 stirrups at 600 mm centres to meet the requirements of NZS 3604:2011 Timber-framed buildings. Unfortunately, this was not reflected in Figure 1 referred to in the text and the note at the bottom of the drawing should be amended to read R10 stirrups. Download amended Figure 1. 
• Fire rating of boundary walls: In general, garage walls within 1 m of the boundary require a 30/30/30 fire rating. That is a wall system that has been tested or assessed to provide a minimum of 30/30/30 fire rating by a recognised authority. There is no specific requirement within the new NZBC clause C Protection from fire Acceptable Solutions with respect to either risk of roof collapse or direction of wall collapse as stated in paragraph 4.4.1 of Bulletin 557 Timber-framed garages. Also B1/VM1 paragraph 2.2.4 modifies clause 4.2.4 of AS/NZS 1170 for specific design by stating that ‘after a fire, a wall must be designed to withstand the most critical of the two situations listed in b(ii) and b(iii) - typically this is b(iii) a uniformly distributed horizontal face load of 0.5 kPa in any direction.
• Structural design: The focus of Bulletin 557 Timber-framed garages is on using NZS 3604 as the design standard. As such, the solution is conservative because NZS 3604 is for the design of importance level 2 (IL2) structures, and stand-alone unoccupied garages are IL1 structures. The design loads for IL1 structures are less than those for IL2 structures. Designers always have the option of using specific engineering design.

Engineering Basis of NZS 3604

Download an amendment to pages 22 and 23 of copies downloaded from our website before 22 April 2013. The current version has been amended.

Good Practice Guide: Internal Lining

Download 2008 update supplement.

Good Practice Guide: Profiled Metal Roofing

The maximum permitted area of roof (in m²) discharging to a given downpipe size given in Table 11 is significantly different from that specified in E1/AS1. This may result in the downpipe being overloaded in maximum rainfall conditions. Please delete Table 11 and replace with Table 5 of E1/AS1. Figure 3 of E1/AS1 may also be used to assist in sizing downpipes for given flow rates.
Some of the illustrations also show an old practice of running insulation blanket over the purlins and immediately under the metal roofing. With this construction, there is a risk that the insulation will absorb condensation and become damp, which may cause corrosion to the underside of the roofing metal. The illustrations are on page 11 (top right), 17 (centre right), 19 (Figure 1), 33 (top right) and 64 (centre left). As more recent BRANZ publications show, roof underlay should come between the profiled metal and the insulation. There should be a minimum 25 mm air gap between the the underside of flexible roof underlay and the insulation.
A new edition of this book is currently in preparation.

Good Practice Guide: Tiling

On page 48, BRANZ recommends a fall of 1:60 for shower bases. Note, however, that in Acceptable Solution E3/AS1, clause 3.35 states:
"Where the shower floor has no upstand or where a wall, screen, door or curtain is omitted, the floor shall have a fall of no less than 1:50 towards the floor waste."

Good Practice Guide: Timber Cladding

For Figure 19 on page 29, the minimum lap for bevel-back weatherboards should be 32 mm (E2, NZS 3617:1979 Specification for profiles of weatherboards, fascia boards, and flooring).

Guideline - November 2006

Download November 2006 update.

Guideline - January 2011

House Insulation Guide (4th edition)

Download 2011 update supplement.

Selecting Timber (3rd edition)

Weathertight Solutions Vol 2: Stucco

All head flashings detailed should incorporate stop ends, because stucco is installed over a cavity. The stop ends have been omitted in drawings 2.1.1.1, 2.1.2.1, 2.1.4.1 and 2.1.5.1. Also, see notes below.

Weathertight solutions details

The DWG/CAD file for WSD 2.1.14.2 Stucco DIRECT-FIXED VERTICAL SHIPLAP WEATHERBOARD JUNCTIONS External corner - vertical shiplap weatherboard - limited risk score is incorrect in existing versions of the stucco collection CD and was incorrect as a download from this website before 18 January 2010. Download the correct version of 2.1.14.2.dwg.