Bushfire Attack Levels
Know your BAL. Understand what it means.
Your Bushfire Attack Level (BAL) can have a significant influence on how and where you build.
Blackash provides site-specific BAL assessments to determine the potential level of bushfire exposure and help clients understand the implications for building design, construction materials and development approvals.
We provide clear, reliable advice to help homeowners, builders, architects and developers make informed decisions from the outset.
What is a Bushfire Attack Level?
A Bushfire Attack Level measures a building’s potential exposure to ember attack, radiant heat and direct flame contact during a bushfire. The BAL classification is determined by factors including surrounding vegetation, distance from the hazard and the slope of the land.
In Australia, the recognised BAL classifications and level of exposure are:
BAL-LOW
Very low risk of bushfire attack
BAL-12.5
Ember attack and radiant heat up to 12.5 kW/m²
BAL-19
Ember attack and radiant heat up to 19 kW/m²
BAL-29
Ember attack and radiant heat up to 29 kW/m²
BAL-40
Increasing likelihood of flame exposure and radiant heat up to 40 kW/m²
BAL-FZ
Direct exposure to flames from the fire front
The assigned BAL informs applicable construction requirements under Australian Standard AS 3959 and the National Construction Code.
