Bushfire Attack Level (BAL) Assessments​

A BAL Assessment identifies the bushfire risk to your property by analysing site-specific factors like vegetation, slope, and fire weather. It’s required when lodging a Building Licence Application in bushfire-prone areas and determines the construction standards needed under AS 3959.

What is a BAL?

When is a BAL Assessment Required?

Owner-Builder Tips

How Does a BAL Affect My Build?

I’ve Got My BAL Rating—Now What?

A Bushfire Attack Level (BAL) is a rating that identifies the potential level of bushfire risk to a building based on the surrounding environment. The assessment considers key site features such as slope, vegetation type and proximity, and local fire weather conditions. From this, a BAL rating is assigned, ranging from BAL-LOW (low risk) to BAL-FZ (Flame Zone, extreme risk).

Each category corresponds with specific construction requirements outlined in AS 3959 – Construction of Buildings in Bushfire-Prone Areas, designed to improve a building’s ability to withstand bushfire impacts.

In Western Australia, a BAL Assessment is generally required when:

  • A new dwelling or habitable building is proposed on land designated as bushfire-prone by the Department of Fire and Emergency Services (DFES).

  • Additions or significant renovations are planned for existing buildings in bushfire-prone areas.

  • You are applying for a Building Licence (Building Permit) in an area where a bushfire hazard has been identified.

Even minor developments may trigger the need for a BAL if they occur within proximity to classified vegetation.

> Tip: You can check whether your property is in a bushfire-prone area by visiting the DFES Map of Bush Fire Prone Areas.

If you're managing your own build, it’s important to:

  • Get your BAL assessment early – Knowing your BAL rating upfront can prevent delays and help guide your building design.

  • Factor BAL construction costs into your budget – Higher BAL ratings can mean additional requirements such as ember-proof vents, non-combustible cladding, or toughened glass.

  • Engage qualified professionals – A credible bushfire consultant will not only assess the risk but can also advise on practical mitigation strategies to help reduce your BAL where possible.

  • Review your site layout – In some cases, repositioning the building or managing vegetation can lower your BAL and reduce costs.

  • Check out our post for a more detailed guide.

Your assigned BAL category directly influences the construction standards required for your project. Higher BALs generally involve increased costs and material specifications to reduce ignition risk from radiant heat, ember attack, or direct flame contact.

For a detailed breakdown of how BAL ratings impact design and construction, read our full blog post: 👉 How Your BAL Rating Affects Your Build

Receiving your Bushfire Attack Level (BAL) rating is a key step in the development process, but it’s only the beginning. Understanding what to do next is crucial for staying compliant, on budget, and on schedule.

What to Do After Your BAL Rating

Once your BAL rating is confirmed, here’s what you should prioritise:

  • Update Your Building Plans
    Ensure your construction drawings reflect the assigned BAL rating and incorporate necessary upgrades, such as materials for windows, doors, roof spaces, and vents, in line with AS 3959 – Construction of Buildings in Bushfire-Prone Areas.

  • Engage the Right Builder
    Choose a builder familiar with BAL compliance and experienced in implementing bushfire construction standards.

  • Plan for Cost Implications
    Higher BAL levels often result in higher construction costs. Be sure to factor in additional expenses for items like glazing, seals, and ember protection early on.

  • Coordinate Your Documentation
    Ensure all documents, including building plans, are updated to reflect BAL requirements before submission to the council or certifier to avoid delays.

Avoid a Common Mistake

A common error is having builders quote based on outdated plans that don’t include BAL compliance. This can lead to budget issues and costly redesigns.

At Bushfire Smart, we guide you through every stage of the process to ensure your build complies with BAL requirements from start to finish.

Need Support?

If you’re unsure about the process, reach out!