AS 3959-2009 Sets The Guidelines for Constructing Homes in Bushfire-Prone Areas
Aust ralia has had a long history of battling with bushfires and grassfires. Bushfires are now a fundamental element of Australia’s environment with its indigenous plants successfully adapting to it by being highly combustible or even needing the fire to regenerate. Many homes in Australia widely used timber in constructing their homes, which make them highly vulnerable. Brick or Concrete houses that use timber flooring may also be impregnable if the sub-floor area is not adequately covered. Timber decking is even more susceptible to ember penetration.
For bushfire-prone areas, the construction of homes is required to conform to the standards set by the government. The Australian Standard AS 3959-2009 Construction of Buildings in Bushfire-Prone Areas provides the guidelines in evaluating the sites that are included under the six bushfire attack levels (BAL: Low, 12, 5, 19, 29, 40 and FZ) and then offers the necessary instructions for constructing home in these sites. The AS 3959-2009 applies to all states and territories not only in the construction of homes but also in relevant extensions or renovations. The primary objective of the standard is to minimize the danger of fire or sparks to penetrate your homes.
Timber used for your homes particularly your timber decking, must not burn readily. The AS 3959-2009 distinguishes three particular kinds of timber and in which category of BAL rating they fall into. These three kinds are those with 650/m³ or higher seasoned density, 750/m³ seasoned density, or timber that are able to resist or endure bushfires. Timber is “bushfire-resistant” if it has one or more of the following properties: its natural fire-resisting quality and if it is mixed or coated with fire-retardant chemicals or substrates.
The good news is that Australia is home to a good handful of high-density timbers that are naturally bushfire-resistant, which is nature’s primary defense against or coping with bushfires. The Standard lists seven species of timber with this innate property, which are durable and compact hardwoods. Research has also proven that these timbers do well in numerous fire-testing. Although the Standard recommends the timber for specific usage, you may still opt to use it more widely for your own comfort and security. For a full list of suitable timbers and its specific usage, see the Appendix E of AS 3959-2009.
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