What is a BAL Rating?
A Bushfire Attack Level (BAL) assessment measures how much risk a building faces from bushfire threats.
Bushfires can impact a property in three main ways:
Ember attack
Radiant heat
Direct flame contact
The BAL assessment follows the method outlined in Australian Standard AS 3959 to determine how likely a home is to be affected during a bushfire. It provides a BAL rating, which reflects the expected level of radiant heat exposure, measured in kilowatts per square metre (kW/m²).
BAL ratings range from BAL–Low (minimal risk) to BAL–Flame Zone (FZ) (highest risk). For example, a BAL–12.5 rating means the building may be exposed to up to 12.5 kW/m² of radiant heat.
To learn more about how bushfires impact buildings, see our article: How a Bushfire Attacks Your Home.
Once the BAL rating is known, a building’s construction can then be adjusted to reduce the possibility a house will be destroyed in a bushfire.
To learn more about what each of these BAL levels mean and the affect they can have on the construction of your building see our other articles here:
What does a BAL rating mean for my house design? Understanding AS 3959: A Plain English Guide for Homeowners