Timber is used extensively in many building types for applications such as floors, walls, ceilings, joinery, furniture, etc.
While the appearance quality is a major factor in the selection of timber species, it is also important to consider performance characteristics such as hardness, moisture movement, fire resistance, etc, appropriate to the particular application.
Installation and finishing practices are also major factors which affect the in-service performance of timber products.
Timber, a natural insulating material, is a very effective building material when considering thermal performance issues. Due to it’s low thermal conductivity, minimises the potential for thermal bridging effects that are present with conductive materials.
The following sections provide useful authoritative information when considering the use of timber in energy efficient designs.
Durability is one of the key performance factors used to assess the suitability of a timber species for a specific application. The durability rating of a species is based on the natural ability of the heartwood of that species to resist decay and insect pests. However, for many species, the durability of sapwood which is usually not durable, may be increased by preservative treatment.
Australian Standards AS 5604 Timber – natural durability ratings and AS 1604 Timber – preservative treatment provide guidance on durability requirements for a range of in-ground and above-ground applications.
Building practice also plays a major role in the durability performance of timber in construction. Information is provided here for recommendations on termite management and detailing for improved durability performance.
Technical Report No 5, Treated Timber in Australia : CCA and the alternatives is a general guide about treated timber and the processes used to treat timber for a wide variety of purposes. The report explains how to be certain the timber you are purchasing is properly treated, and why this is important. A number of helpful tables will also assist you to make well-informed treated timber selections according to the requirements of the particular building task at hand.
A separate section introduces Standards Australia’s AS1604-2000 series, which contains the preservation requirements for round and sawn solid timber, and wood-based composite products like particleboard, plywood, LVL and glue-laminated timber. The list of more detailed publications and URL addresses of some useful websites on this subject will benefit those interested in finding out more about preservative treated timber in Australia .