If your block is bushfire-prone, your BAL rating shapes what you can build with. Here is a plain-English explainer.
What BAL means
Bushfire Attack Level rates a site's potential exposure to bushfire under AS 3959, from BAL-LOW up to BAL-FZ (Flame Zone). The higher the rating, the greater the radiant heat, ember and flame exposure your building must resist.
Why it affects cladding
Higher BAL ratings restrict combustible materials, which often rules out the natural timber cladding owners want. Eaves, windows and decks - the vulnerable spots where embers lodge - get particular attention.
Where aluminium fits
The aluminium substrate is non-combustible to AS 1530.1, so it is a sensible starting point on BAL-rated land, especially for eave and soffit linings. Final compliance is always assessed on the complete wall build-up, not one product.
Get the rating first
Have your BAL determined by a qualified assessor before locking in materials. It changes what is possible, and designing to it from the start is far cheaper than retrofitting compliance later.