Building safe homes in bushfire prone areas

Australia is affected by more than 50,000 bushfire events every year. As a significant proportion of Australians live immediately adjacent, or very close to, bushfire prone areas, it is critical for designers and specifiers to understand how to construct homes that can withstand bushfire damage.

Understanding Bushfire Attack Level (BAL) Ratings

The risk of bushfire in different environments is measured in terms of Bushfire Attack Level (BAL). Under AS 3959-2009 Construction of buildings in bushfire-prone areas, the BAL rating system is divided into six levels ranging from BAL-LOW (very low risk of exposure to fire, ember, or radiant heat) to BAL-FZ (extreme risk with direct exposure to fire, ember, or radiant heat).

Aluminium: A Fire-resistant Solution

When designing for bushfire prone areas, designers should consider non-combustible, fire-resistant building materials such as aluminium. Solid aluminium has a high melting point and high thermal conductivity allowing it resist fire for extended periods and making it less prone to ‘hot spots’ where concentrated damage can occur.

Compliance

According to AS 3959-2009, all cladding and roofing systems used in BAL zones must be tested in accordance with AS 1530.8.2-2007 Methods for fire tests on building materials, components and structures. This Standard covers the testing of building elements exposed to simulated bushfire attack.

To ensure compliance with the relevant Australian Standards when designing for buildings in bushfire prone areas, the following steps should be taken:

1. Consult the relevant State or Territory bushfire map to determine whether the development site is in a bushfire prone area. If so, any building work will require a BAL assessment. 2. Once the BAL rating is determined, the next step is to look for cladding solutions that correspond with the given rating.

In Australia, a new generation of aluminium cladding products have demonstrated compliance with all AS1530.8.82-2007 requirements and are suitable for use in environments rated up to BAL-40.

Wintec Systems

Since 1997, Wintec Systems has led the Australian market in high performance aluminium products that deliver function, style and innovation. All Wintec products are designed, tested and manufactured in Australia and comply with the relevant Australian Standards. This includes Ulltraclad, a fullyintegrated aluminium weatherboard solution for use as a complete external cladding system for residential and light commercial buildings.