Everything you need to know about BAL ratings. Bushfires are a common occurrence across Perth in our hot summer months. As climate change continues to fuel more hazardous bushfire seasons, measures have been placed to protect people and homes from harm.
One of the most important measures in place is the Bushfire Attack Level (BAL) rating. BAL is an Australian Government standard that measures a home’s potential exposure to bushfire attacks (radiant heat, embers and direct flame contact).
At Fox Granny Flats, our team is committed to creating homes that meet the highest safety, functionality and quality standards. Our commitment includes incorporating design principles to meet BAL requirements as needed.
What are the BAL ratings?
First things first. What are the different BAL ratings, and what do they mean? A BAL rating is given to homes in bushfire-prone areas and governs the building requirements and construction methods necessary to offer increased protection.
There are six levels of BAL ratings in accordance with the Australian Standard 3959. The ratings are measured in increments of radiant heat exposure in kilowatts per square metre. These include:
- BAL-LOW: Insignificant radiant heat exposure. Low risk; no specific construction safety requirements apply.
- BAL-12.5: 0 – 12.5kW/m2 radiant heat exposure. Some risk of ember attack; some construction safety requirements apply.
- BAL-19: 12.5kW/m2 – 19kW/m2 radiant heat exposure. Moderate risk of ember attack and exposure to radiant heat; some construction safety requirements apply.
- BAL-29: 19kW/m2 – 29kW/m2 radiant heat exposure. High risk of ember attack and increasing exposure to radiant heat; more extensive construction safety requirements apply.
- BAL-40: 29kW/m2 – 40kW/m2 radiant heat exposure. Very high risk of ember attack, increased exposure to radiant heat and possible exposure to direct flames. More extensive construction safety requirements apply.
- BAL-FZ: 40kW/m2 plus radiant heat exposure. Extreme risk of direct exposure to flames, high levels of radiant heat and ember attack. Extensive construction safety requirements apply.
What a BAL assessment will include
To determine whether the location you’re looking to build in is a bushfire prone area, start by visiting the DFES website. This has a handy map that shows the various bushfire-prone locations throughout WA.
The next step is to have a qualified professional conduct a BAL assessment of your building site. This will include:
- A site analysis and classification of vegetation types within 150m
- Measuring the distance between the vegetation and proposed building site
- Determining the slope of your property
- Calculating the BAL
- Recommending construction requirements and other safety initiatives
Depending on your BAL rating, adding fire-resistant design features to your home will involve additional costs. Some of the design and construction considerations include:
- Use of non-combustible roofing materials (such as steel)
- Installing thicker, tougher glass and fire-resistant frames
- Using non-combustible materials for decking and flooring
- Ensuring gaps are sealed to prevent build-up of embers
- Adding a gutter guard to prevent build-up of leaves
- Using non-combustible materials or BAL-rated external cladding for external walls
Get the peace of mind you deserve
At Fox Granny Flats, our highly experienced team can help you navigate any BAL requirements for your new dwelling. We will work closely with you to highlight the design considerations required, ensuring your new home ticks all the boxes for safety.
To find out more about what’s involved, or for more information about our range of designs, speak to our friendly team today.