About the Framing Code - AS1684

AS1684 has been around for a number of decades, however each State produced their own specialised framing manual that reflected their market requirements. For instance Queensland builders remember the old TRADAC W33 manuals and the others within this set.

A National agreement between all states and Standards Australia has seen the revision and complete adoption of AS1684 as the primary document for residential timber framed construction throughout Australia.

The BCA (Building Code of Australia) also recognizes this fact, and calls up this document under the code. TQL fully supports this Standard and provides advice on technical implementation of this document.

A totally new edition of AS1684 Parts 2, 3, and 4 was published in January 2006 (Refer to Fact 4 below for more details). Copies of the Standard can be purchased from Timber Queensland who can also provide technical advice and information on the latest editions and amendments.

Facts about AS1684:

1. The classification of wind speed has changed. N = Non-cyclonic / C = Cyclonic. (New - old)

• N1 - (W28N) / C1 - (W41C)
• N2 - (W33N) / C2 - (W50C)
• N3 - (W41N) / C3 - (W60C)
• N4 - (W50N)

2. No hard copy span tables can be found within the document (except AS1684.4), they are provided on a CD-Rom located inside the back cover of the Standard.

3. You can use them right across Australia, not having to use specific state based manuals.

4. Residential Timber Framed Construction. This is a four-part Australian Standard covering design criteria, building practice, tie-down, bracing and span tables for timber framing members. The Standard is 'deemed to satisfy' under the Building Code of Australia. The four documents are:

There are 4 parts to AS1684:

• Part 1 - Covers the design criteria
• Part 2 - Construction details for Non-Cyclonic areas (N)
• Part 3 - Construction details for Cyclonic areas (C)
• Part 4 - Is a Simplified manual for N1 conditions only.

Part 1 Design Criteria (AS 1684.1) Sets out the basis for the calculation of timber sizes and forces to be resisted by tie-down and bracing. It provides a standard reference for designers and product manufacturers to produce engineering solutions compatible with AS 1684. Current amendments to 1999 Edition: Amendment 1 - February 2002

Part 2 Non-cyclonic Areas (AS 1684.2) This part covers design and construction details for non-cyclonic areas. Four design wind classifications are covered including N1, N2, N3 and N4 (previously 28, 33, 41, 50 m/s). Span tables for all these wind classifications and 15 selected timber stress grades are provided on CD as part of the Standard. 

• Current Edition - 2006

Part 3 Cyclonic Areas (AS 1684.3) This is similar to Part 2 except that it covers design and construction details for cyclonic areas. Wind classifications covered are C1, C2 and C3 (previously 41C, 50C and 60C).

• Current Edition - 2006

Part 4 Simplified / Non-cyclonic Areas (AS 1684.4) This part provides simpler design procedures than those contained in Part 2, for N1/N2 wind classifications only. In some situations it will provide more conservative solutions. The scope of Part 4, including house geometry and range of stress grades is also more limited. Span tables are printed within this part.

• Current Edition - 2006

5. What are the benefits of using AS1684?

In some cases the new manuals provide more efficient and competitive selection of timber members for construction - therefore providing cost saving benefits for you the builder. One of the biggest advantages is that we now have a single framing manual that covers all of Australia.