A planning expert has warned that houses in bushfire-ravaged towns should not be rebuilt http://www.abc.net.au/news/2017-01-06/bushfire-ravaged-towns-should-not-be-rebuilt-expert-warns/8166178
Anyone planning to build, rebuild, retrofit or repair home to be bushfire resistant needs to be aware of the failings in the relevant building regulations (Australian Standard Construction of Buildings in Bushfire Prone Areas).
They cannot be relied upon to provide bushfire safety.
These are some of their extraordinary omissions and inclusions:
- Ignore the roof/ceiling space. Of the three core vulnerable areas: subfloor, windows and roof space, this is the most dangerous aspect: because it is unseen.
- Stipulate brick for the worst danger categories. Look at all the brick houses destroyed during bushfires.
- Allow brick veneer. Air space between external and internal wall linings encourages upward spread of fire
- Stipulate that timber cladding must be ‘fire retardant’-which is pointless: the danger to houses only comes from the outreach of flames if vegetation is allowed to grow close.
- Stipulate metal frames, known to buckle under intense heat.
- Allow polyurethane for insulation -a killer that gives off cyanide gas within 30 seconds of smouldering
- Ignore the type of internal wall linings – though many give off toxic gases when burning
- Ignore the type of water tank – plastic tanks melt in intense bushfires.
- Ignore the type of farm fencing – metal picket posts survive and will keep the wiring upright.
- Designate a site category the ‘flame zone’ – to allow home building anywhere near a ‘flame zone’, is homicidal.
The three core home destroyers
1. Embers, embers, embers. Not the fabled ‘sweeping flames’.
2. Flames – rarely, depends on your vegetation management.
3. Radiant heat – if ever, from closely adjacent building.
The three core areas for ember protection
1 Roof/ceiling space
The three core areas for flame protection
1.Lessen nearby vegetation density and flammability
2. Increase distance between cladding and flammable vegetation.
3. Maintain spaced plants, fire resistant plants, cleared ground beneath plants.
The three core construction protections for houses
1. Clear roof space, insulate, ember-proofing potential entry points.
2. Cover windows with shutters or metal flywire
3. Cover subfloor gaps with metal flywire
To each core point add:
Thorough knowledge of what to do, when to do it, and why.
ESSENTIAL BUSHFIRE SAFETY TIPS is the ONLY publication for the householder that details all up-to-date known and proven factors of involved in personal and home danger and safety during bushfires and provides options for reacting to them. Every word has been checked and rechecked by senior CSIRO bushfire scientists. It is endorsed by the Country Fire Authority, Victoria:‘Truly an outstanding achievement and a book that certainly could help save lives within the community.’:
Click here http://www.publish.csiro.au/pid/6969.htm