"FRAMEMAN has preferred
IT TOOK less than a minute for this new house to be engulfed by flames. Luckily no one was too upset to see it burn.
The house, built almost entirely of steel, was being tested to see if it could survive a bushfire and, although it is now a little singed, it passed.
Not only was it still standing, if it had been occupied there was a good chance the people inside would have survived, the CSIRO scientist and test leader Justin Leonard said.
The test house, designed and built by the National Association of Steel Framed Houses with the CSIRO, had most features of a domestic house.
Mr Leonard and his team, aided by the Rural Fire Service at Mogo on the south coast, mimicked the conditions of a bushfire in the test. First the house was subject to radiant heat from gas burners placed metres away for more than half an hour, imitating a bushfire's approach.
Gradually the intensity of the gas burners grew until the house was engulfed in flames three metres high for nearly two minutes.
According to Mr Leonard, the test house underwent an "extreme" bushfire scenario. "The duration of the flame immersion was longer than a bushfire could possibly dish up," he said.
At its peak, the temperature of the fire would have been more than 1000 degrees.
The full effect of the fire on the house still needs to be assessed, but the researchers believe the design could be an affordable option for construction in bushfire-prone areas.
During the "Black Saturday" bushfires in Victoria in February last year more than 2000 homes were destroyed by fire.
Unlike most houses, the test house minimised to use of elements that could be combustible. Its frame, walls, floor and roof cavities were all made of steel. The thermal insulation and the plaster walls and ceiling acted as another fire-proof barrier.
"All the layers work together as a system to protect the occupants," Mr Leonard said.
While people are not encouraged to stay in their house during a bushfire, Mr Leonard said if people did not get sufficient warning it could become unsafe for them to leave their property.
"We're testing the house's ability to create a safe place of refuge during the time you'd be forced inside the house if you were unlucky enough to be there."
Mr Leonard said the flame test would help the researchers explain to builders how they should construct houses to make them "inherently robust" for bushfires.
Nicky PhillipsApril 17, 2010