Roof Trusses and Wall Frames

What are the Australian standards for roof trusses and wall frames?

All suppliers of timber roof trusses and timber wall frames are required to comply with Australian Standards for all commercial and residential projects.

These Standards codify best practices, technical requirements, and methods necessary to create a safe and sustainable built environment. These documents often include information on building materials, guidelines, procedures and testing criteria.

Read our blog on Australian standards for timber wall frames and trusses so you know what to expect when it comes to hiring a construction service.

Timber wall frame specifications

The AS 1684.2—2010 outlines the requirements for residential timber-framed construction in Australia. Some important standards outlined in the document include:

  • Timber walls are to be framed with the appropriate use of noggings, studs, plates, lintels, bracing, and similar members.
  • Temporary bracing is required throughout the construction of timber walls.
  • External walls need to be laterally supported to protect from high wind forces.
  • Lateral support is required for external timber walls that support ceiling joists, rafters or trusses.
  • Noggings are to be used between studs to provide lateral support.
  • Non-load bearing walls – including verandah walls and gable end walls – shall be laterally restrained at a maximum of 3000 mm
  • Timber wall frames are to typically remain either 90mm or 70mm deep with 35mm or 45mm thick studs depending on spacing and load.

Truss installation standards

The AS4440-2004 outlines the standards for the bracing, connection and installation of timber roof trusses. It states:

Before installation

Roof Trusses And Wall FramesBefore installation, Australian Standards require that a layout with sufficient information be in place. This layout should correctly locate the timber trusses and, where information is unclear, clarification should be sought before beginning construction.

Construction workers must carry out the relevant workplace safety practices and conduct a risk assessment of the construction site before getting started.

To guarantee correct timber roof truss positioning, the Standards recommend marking the location of the truss on the top plate or other supporting elements as the design layout dictates.

During installation

During installation, it’s essential that all trusses are braced (either temporarily or permanently) for adequate stabilisation and to ensure they hold straight. Without temporary bracing in place, nail-plated trusses should avoid being loaded in any capacity.

If labourers default on these bracing requirements, some potential consequences include the collapsing of trusses or irreparable damages caused by overloading and buckling.

Installation of the brace takes place once the truss has been erected correctly and is straight and vertical. This is then used as a guideline to set other trusses in line.

It’s essential that the temporary brace remains in place until a permanent bracing has been installed.

In terms of specification criteria, the following requirements are necessary:

  • The truss must have a minimal bow with tolerance below L/200 and 500 mm.
  • No part of the truss should be out of plumb with a tolerance exceeding a lesser of 50 height and 50 mm.

Roof Trusses and Wall FramesWhen it comes to modifications, the use of drilling, cutting, or any other method that may compromise the structural integrity of the truss can go ahead without being approved first.

Newcastle Frame & Truss is committed to ensuring that Australian Standards are met when it comes to the installation and maintenance of timber roof trusses and wall frames. Contact us at Newcastle Frame and Truss www.newcastleframentruss.com.au or call on 0437 437 231.

We service the areas of Adamstown Heights, Birmingham Gardens, Bar Beach, Broadmeadow, Northern Sydney Newcastle, Callaghan, Hunter Regions, Black Hills, Wyong, Beresfield and surrounding areas.