BAL bushfire ratings explained (and what they mean for your build)

If you are building on the South Coast, you will hear the term BAL early. It is not red tape for its own sake: it is what keeps a home defensible in a bushfire, and it has real design and cost implications.

What BAL means

BAL stands for Bushfire Attack Level. It is a measure of how much bushfire risk a building is likely to face, from BAL-LOW through BAL-12.5, 19, 29, 40 and BAL-FZ (Flame Zone). The higher the rating, the more the building must resist radiant heat, embers and direct flame.

How it is assessed

The rating depends on the vegetation around your site, the slope and the distance between the house and the bush. A bushfire assessment determines the BAL for your specific build, and it is worth doing early because it shapes the design from the start.

What it changes in the build

Higher BAL ratings dictate cladding, window glazing, door seals, decking material, subfloor protection and screening to keep embers out. The jump from a low rating to BAL-29 or BAL-40 can be significant across a whole house, which is exactly why we factor it in from the first sketch rather than discovering it at certification.

How Perrem handles it

We manage the bushfire assessment and design to comply in-house, so your home meets its rating without the design feeling like a compromise. Building to a high BAL well is a craft, and it is one we practise often on this coast.