The Black Saturday bushfires that swept across Victoria early last year destroyed lives and properties on a scale never seen before. These events set in motion a review of regulations that have changed the way the building industry will function forever – not just in Victoria, but across Australia.
The fires destroyed over 2,030 houses (3,500-plus structures in total) and damaged thousands more. In all, 173 people died and 414 were injured. As a result, new regulations were applied to building permits from March 11, 2009. There are now six Bushfire Attack Level (BAL) ratings compared to three prior to Black Saturday, with specific construction requirements each.
The BAL ratings include:
- BAL – Low (No regulations apply)
- BAL – 12.5 (Ember attack only)
- BAL – 19 (Increased ember attack and radiant heat)
- BAL – 29 (Increased embers, burning debris, increased radiant heat)
- BAL – 40 (Increased embers, burning debris, increased radiant heat and likely flame contact)
- BAL – FZ (Flame Zone – direct exposure to flames, embers and radiant heat attack).
The number after the BAL is based on heat flux exposure thresholds (radiant heat) in kW/m2. This increased stringency means that building material suppliers have been forced to improve the quantity and quality of supplies such as internal floor coverings, decking, window frames and roof tiles.
These improvements will have far reaching affects for the national building industry because interstate builders will have access to improved materials and the knowledge that they are of the highest bushfire resistant standards. James Hardie’s Darren Nixon, who serves as Chairman of the Master Builders Association of Victoria’s Manufacturing, Materials and Supplies Committee, explains the changes. “I think its two parts. Some suppliers have had to change their products to meet the regulations and then others, like James Hardie, have been able to adapt their current range. “The key is communication with the builders that are trying to meet the regulations, so they know what products are available to meet the different parts of the regulations. There’s definitely a higher benchmark now, but the thing that is most concerning to our industry is housing affordability.”
Among the other Australian suppliers who have taken a lead role in developing fire-rated materials is Boral Bricks, whose clay bricks are fired at temperatures higher than anything reached in a bushfire. Bricks are also kilned for much longer than it takes for the front of a bushfire to pass. Studies have found that masonry walls significantly reduce the chances of a house being destroyed by a bushfire. Marketing Manager for Boral Plasterboard, Victor Avrutis, said that Boral offered a range of materials that are ideal for using in bushfire prone areas. “Boral has a variety of lightweight fire solutions that satisfy bushfire requirements. These solutions offer the designers, builders and owners of bushfire-prone buildings the flexibility of design and construction and provide cost-effective alternatives to traditional construction methods,” he said.
Victoria’s Black Saturday bushfires were among the most severe ever experienced. But every Australian state has areas that are equally vulnerable, and the new BAL ratings are sure to set a benchmark for future bushfire zone building regulations in those areas. The standard is designed to improve the performance of buildings when they are subjected to bushfire attack in the designated bushfire-prone areas. However, there can be no guarantee that a building will survive a bushfire event on every occasion.
Suppliers need to be aware of the importance of these changes. They must also be prepared for the increased demand as the bushfire rebuild continues and new home builders in all states begin demanding these high quality supplies. For more information, builders are encouraged to look at the websites of their local suppliers or visit www.dse.vic.gov.au.
Laura Luvara is the Media Advisor for the Master Builders Association of Victoria.