October 13, 2022


BAL and Your Level of Risk


The level of bush fire risk affects building development requirements across Australia. The higher the risk, the more protection you need. We use the term ‘bush fire attack level’, or BAL, to quantify this risk. If you are looking to include skylights in a new building development or home renovation you will need to consider BAL rating that applies in your area.


Your BAL level is affected by the area you live, the vegetation, the distance from the vegetation to your home, and the gradient of your property and slope of the surrounding land. As part of any development, rebuild or renovation approval process, you will need to ascertain the BAL rating applicable in your area to ensure it meets the BAL rating requirement. Your local council or RFS will be able to help you identify what the BAL rating is in your area, or you can use a Fire Protection Consultant to advise.


There are six bush fire attack levels (see table below). BAL-Low is the lowest bush fire risk and Flame Zone (BAL-FZ) is the highest.



Bush Fire Attack Level



Description of risk


Lowest risk from a potential fire.

BAL – 12.5

Risk is primarily from potential embers during a fire.

BAL – 19

Moderate risk, particularly from embers and burning debris.

BAL – 29

High risk, particularly from embers, debris and heat.

BAL – 40

Very high risk. Likely to be impacted by embers, debris, heat and potentially flames.


Extreme risk. Directly exposed to the flames of a potential fire front.


With regard to skylights, they will either be unrated (i.e. not tested and approved for any particular BAL rating) or they will come with a designated BAL rating as documented by the manufacturer.


Roof penetrations of any kind are not recommended in BAL-FZ areas, and there are currently no commercially available BAL-FZ rated skylights available in the Australian Market.


There are a number of commercially available products – such as Keylite Skylights – which have been tested and approved for use in areas with a BAL-40 rating.


Single-Glazed Glass skylights that are made from non-combustible materials – such as Natural Lighting Product’s range of glass skylights – are suitable in areas with a BAL-29 rating with the appropriate engineering certificate provided by the supplier.


Acrylic domed skylights are not appropriate for use in areas with a BAL rating of 19 or above.


If your local council or development approval requires a particular BAL rating on any skylights planned for your development or home, ask your supplier to confirm in writing their products meet the requirement to give you peace of mind!