In the final part of our standards spotlight series we focus in on AS 1684.2:2021 Residential timber-framed construction, Part 2: Non-cyclonic areas and AS 1684.3:2021: Residential timber-framed construction, Part 3: Cyclonic area – the pre-eminent design and construction documents for residential timber framing in Australia.

If you’d like to go back and see the other parts of our series, click on the relevant links: Part 1 – Emergency lighting and exit signs for buildings, Part 2 – Fire hydrant installations, Part 3 – Plumbing and Drainage – Water Services.  

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What is AS 1684.2:2021?

AS 1684.2:2021 specifies requirements for building practice and the selection, placement and fixing of the various structural elements used in the construction of timber-framed Class 1 (houses) and Class 10 (i.e. garages) buildings as defined by the National Construction Code (NCC). The provisions of this standard also apply to alterations and additions to such buildings.

AS 1684.2:2021 is referenced in both Volume One and Volume Two of the NCC. The latest version of the standard supersedes AS 1684.2-2010 as a primary referenced document in the NCC 2022.

Together with AS 1684.3:2021 (cyclonic areas) – which provides alterations for wind classifications C1, C2 and C3 cyclonic areas – the standards represent the pre-eminent design and construction documents for residential timber framing and are a primary source for building certifiers to attain compliance.

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Who are these standards for?

Homeowners, architects, home builders, surveyors/certifiers, building designers, roofing carpenters, engineers, local councils, regulators, the solid timber flooring industry, timber manufacturers and suppliers.

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What’s changed for NCC 2022?

For most people, the family home is the single most valuable investment in their lifetime, with timber being the most popular choice of building material to construct homes in Australia.  

The revised standards help to promote more robustly built buildings across Australia that are able to withstand high winds or other environmental stresses – a critical issue as we face more and more extreme weather events due to climate change.
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Summary of key changes

The Australian construction environment is undergoing significant changes due to technological innovation, macroeconomic factors such as rising labour and materials costs, supply chain issues, the shift from traditional hardwoods to softwoods and engineered timber, the advent of new types of building practices, and the impact of climate change.  

These can bring opportunities as well as challenges.

Innovation in roofing systems can involve changes in materials and construction practices leading to higher productivity. However, innovation can also increase risk where new materials, accepted standards and traditional construction practices are not in alignment.

Defective or incorrect construction practices can pose safety risks and impose substantial financial costs in terms of damages to housing following high-wind events.  

The standard aims to improve industry guidelines and clarity in this critical area of construction.

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Changes to the standard include:

• Creating up-to-date guidelines to address new trends in timber such as the rise of engineered wood.
• Providing additional details for roofing carpenters on how to connect metal roof battens to timber roof framing.
• Providing details on how to fix masonry tie-down straps to timber-framed roofs.
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Both AS 1684.2:2021, Residential timber-framed construction, Part 2: Non-cyclonic areas and AS 1684.3:2021, Residential timber-framed construction, Part 3: Cyclonic areas are available via the Standards Australia Store and our distribution partners.

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