Fire-proof buildings mooted for bushfire affected areas flawed – CSIRO
Fire-proof buildings mooted for bushfire affected areas flawed – CSIRO
1 April 2009
published by www.news.com.au
Australia — Serious doubt has been cast over the safety of houses to be rebuilt after the Black Saturday tragedy.
The nation’s peak science body has warned the new building standard announced last month contains some significant flaws.
The CSIRO is concerned that sections of the code could take some new Victorian homes back to lower standards than before the fires.
Shortcomings include the safety of new building materials, the gaps between wall and roof cavities and protection for exposed sub-floor areas.
The CSIRO wrote to Premier John Brumby last month warning of the dangers of the new building codes.
CSIRO research scientist Justin Leonard told the Herald Sun that more work needed to be done.
Mr Leonard said: “We’ve certainly got some reservations with the new standard that’s come out and a number of deficiencies around that standard.”
The CSIRO will this week with with the Australian Buildings Code Board to discuss their concerns.
ABCB general manager Ivan Donaldson said the new standard was the toughest yet and had been backed by up to 17 different bodies.
But Mr Leonard said the new regime removed protection for sub-floor areas.
This meant that houses with raised floors could become exposed to embers and sparks because of unprotected space.
Sub-floor space should be enclosed to protect areas exposed to fire.
Under the previous standard, gaps of up to 1.8mm were allowed for wall and roof cavities.
These had now been widened to 3mm.
“So there’s a significantly higher chance of ember entry into the various areas in the house,” he said.
There also were issues with the loosening of requirements for the combustibility of various materials outside houses.
Mr Leonard said the CSIRO wanted to work towards making buildings safer.
“We want to continue to work with all the parties towards a safer and sustainable building code for Australia,” he said.
“We’re very keen to engage and improve it in these ways.”
Mr Brumby last month announced what he said were tougher building requirements for homes in high bushfire risk areas.
The CSIRO voted against the standard being adopted.
Under the new code, homes in the most extreme fire risk areas would have to have a concrete slab, exterior walls would have to be brick or concrete, wall and roof joints sealed, aluminium shutters installed and metal gutters and down pipes.
The new standard will be judged according to six different bushfire attack levels.
They will cost some home-builders an extra $20,000-a-year.
The Government said the new standard was the highest available.
Spokeswoman Sofia Dedes said the Government would consider altering standards if recommended by the royal commission.
“The Victorian Government has adopted the highest standard available,” she said.
“It is more stringent and better targeted than the previous standard.
“This standard was due to be adopted nationally in May 2010, but in light of the devastating bushfires, the Government brought forward the adoption date to allow Victorians to rebuild their homes.
“Under the previous standard, only homes in bushfire prone area were covered. The new standard is state-wide, allowing for a site-by-site assessment of homes to offer people across the state the highest protection available.”
