Fire Resistant Roof Sydney Promatect 40 by Promat

Considerable resources help Australians cope with the annual bushfire risk. Many houses employ inherently fire resistant walls but, paradoxically, roof structures are often overlooked.

In a typical scenario, the flame front approaches with alarming speed, passing by in a mere two to three minutes. However, temperatures can escalate rapidly to around 1200 degrees.

The effect of these extreme temperature on a roof and, equally important, the underlying support structure have been unknown until fairly recently.

Tests now clearly indicate that even after the fire front has passed, combustibles such as timber framing contain residual heat which can continue to grow. In turn, even after considerable time, ignition can then occur within roof spaces and wall cavities, with unsuspected and frequently tragic results.

A new test method AS1530.8 Part 2 allows for a 30 minute flame exposure followed by a 60 minute observation period. The flame exposure period has a large safety factor, given the relatively brief but intense nature of most passing bushfires.

The flame exposure component of the test uses the ISO and AS time temperature curve which is followed by a 60 minute monitoring phase, critical to ensure no re-ignition of the (roof) specimen occurs. Radiometers are used to ensure heat from the specimen is not increasing, as this would indicate continuing combustion from within the system.

The development of a compliant roof system - jointly funded by Forest and Wood Products Australia Limited, Bluescope Steel Limited and Promat Australia Pty Ltd - is a cooperative approach that meets requirements of the most extreme bushfire attack level under the new Standard.

A Promat solution for the main roof using PROMATECT 40 boards has been successfully tested at Exova Warrington, a NATA approved facility, and is now on the market.

It's reassuring to note that PROMATECT 40, manufactured according to environmentally correct green principles, can now do so much more to protect real life and property from the extremes of hostile environment phenomena.