Structural frames made from wood or timber have been used to build houses, barns, churches, factories and stables for so many years that the real origins of the many systems would be difficult to establish.
Various publications have described the systems used in the Australian states over the last 200 years but for the builder of today and tomorrow, it is essential that he or she is continually assessing the changing scene in terms of new systems, new building codes or regulations and particularly new products, of availability and prices of all materials.
From the early 1990's, it is expected that a basic building code will apply throughout all states of Australia, thus for the first time introducing a reasonable level of uniformity between local government authorities in the application and interpretation of building regulations, specifications or
This new Building Code of Australia, as it is titled, will introduce some variations in practice with regard to timber usage in non domestic buildings. However, for domestic building (i.e. one and two storey houses) in New South Wales, little real change will be generated as regards to timber framing compared to what is now written into Local Government Ordinance 70 in 1989.
For example, for timber framed dwellings, the revised Local Government Ordinances will still require that all structures and members of timber shall be:
(a) designed and erected in accordance with the principles of structural mechanics; and
(b) capable of sustaining the most adverse combinations of loads to which they will he subjected in accordance with the other provisions of this (Local Government) Ordinance
The Timber Framing Codes
For a conventional timber framed house, the ordinances will accept that a timber frame. designed and built according to the Australian Standard AS1684 "Code of Practice for Construction in Timber Framing" (known as
the Timber Framing Code), can be 'deemed-to-comply with the above requirements if erected on a typical suburban site.
For unconventional timber framed housing the approving authority will accept that Australian Standard AS1720 The Timber Structures Code can be utilised in design but will require some professional expertise to verify that the proposed design meets the above stated principle.