A Bushfire Attack Level (BAL) is a system used in Australia to assess the potential risk of a building or structure to bushfire, this assessment is based on the potential exposure to ember attack, radiant heat, and direct flame contact. The severity of these hazards is measured in increments of radiant heat, which is expressed in kilowatts per square meter (kW/m2) – Certainly, something worth investigating when looking at a property project, whether it be for development, investment, or your principal place of residence.
Why should you care? The BAL assessment is important in determining the requirements for construction in bushfire-prone areas, it could mean your new building needs to be a concrete bunker, or has no hazard whatsoever. It is used as the basis for establishing the specific construction standards outlined in the Australian Standard AS 3959-2009 Construction of Buildings in Bushfire Prone Areas and provides guidelines on how to improve the resilience of buildings and structures to bushfire attack.
During the development planning and construction process, a BAL rating is assigned to a building or building pad based on its setback from fire-hazardous vegetation. This rating will determine the specific construction requirements that must be met in order to improve the building’s ability to withstand a bushfire. For example, a building with a higher BAL rating may require more fire-resistant materials and construction techniques than a building with a lower BAL rating. As you could anticipate, this can also significantly impact the cost of construction so best to discover the BAL rating as early as possible in a project.
For reference, there are six different Bushfire Attack Levels (BALs) used in Australia:
- BAL-LOW: The lowest level of risk, where the building is at minimal risk from ember attack, radiant heat and direct flame contact.
- BAL-12.5: A moderate level of risk, where the building may be at risk from ember attack and radiant heat, but not direct flame contact.
- BAL-19: A higher level of risk, where the building may be at risk from ember attack, radiant heat and potentially direct flame contact.
- BAL-29: A very high level of risk, where the building may be at significant risk from ember attack, radiant heat and direct flame contact.
- BAL-40: An extreme level of risk, where the building may be at significant risk from ember attack, radiant heat and direct flame contact, and also exposed to intense radiant heat.
- BAL-FZ (Flame Zone): The highest level of risk, where the building is in an area where there is a high likelihood of direct flame contact.
It’s important to note that, whilst a BAL rating is a good tool to evaluate the risk of bushfires, it’s not a guarantee of safety, and it’s important for building owners to take additional steps to protect their property from bushfires. This might include creating a bushfire survival plan, maintaining their property in a fire-safe manner, and staying informed about bushfire risks in their area.
Unsure if your project needs a bushfire consultant involved? Please feel free to reach out to one of our staff in the below contact form.
Learn more about our Bushfire Hazard and Management services here: https://newground.com.au/bushfire-hazard-assessment-and-management/