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Requirement for BAL reports (Bushfire Attack Level) for Garages, Carports, Sheds, Patios and Decks.

If you are considering doing residential building work in a designated bushfire prone area you may be required to comply with the bushfire construction requirements of the Building Code of Australia (BCA).

This will require compliance with Australian Standard AS-3959 – Construction of buildings in bushfire prone areas and may trigger the need for a BAL assessment to be undertaken before works can begin.

The BCA bush fire construction requirements applies to Class 10a buildings located in designated bush fire prone areas

Any associated structures such as garages, carports, patios, decks or verandas that are attached or adjacent to a house may need to comply with the requirements of the BCA and AS 3959. This could mean that the structure will need to meet the same construction requirements as the house, or be adequately separated from the house either by the nature of its construction or by its distance (6m or more) from the house.

Construction of buildings in bushfire prone areas may trigger the need for a BAL assessment to be undertaken before works can begin.

- Class 10a buildings and decks associated with Class 1a, Class 1b, Class 2 or Class 3 buildings.

- Class 10a buildings incl. non-habitable buildings such as garages, carport, patios, sheds or the like.

What is a Bushfire Attack Level (BAL) Report? A BAL assessment is prepared by a suitably qualified BAL assessor and is designed to determine the Bushfire Attack Level (BAL) of an individual property. Levels are defined in six (6) categories BAL-LOW, BAL-12.5, BAL-19, BAL-29, BAL-40, and BAL-FZ (Flame Zone) and are based upon the regions Fire Danger Index, (FDI) for the property, (for Perth this is recognised as an FDI of 80), the vegetation type around the property, the distance to individual vegetation types and the slope under the vegetation affecting the property.

Once the BAL is determined the construction standard of the new development or building works can be determined using Australian Standard AS-3959.

For example, BAL-LOW has no effect on construction standards whilst BAL-FZ adds very stringent construction standards.

Are there any exemptions from getting a BAL Assessment? Some local councils and shires provide exemptions for certain types of development, however, the Building Code of Australia, (BCA) calls up AS-3959 for all applications where the property is within a Bushfire Prone Area. This means that if you have been given an exemption in regards to applying for a Planning Application due to the Scheme provisions you will still need to have a BAL assessment undertaken for your Building Application.

AS-3959 however, does provide for some exemptions these being a detached roofed structure such as an outbuilding, shed, garage, carport, etc, that is more than 6m away from property’s residence. Or alternatively the structure is designed to comply with clause 3.2.3(b) or (c) of AS3959 that is, be designed to provide a minimum fire resistance level (FRL) of 60/60/60, (1 hour fire rating).

What can I do to decrease my BAL? You can decrease your BAL by having a Bushfire Protection Zone (BPZ) that is a 20m circular area clear of vegetation and other flammable materials around your home. A BPZ is also referred to as an Asset Protection Zone.

(See the ‘What is a Bushfire Protection Zone’ PDF available from the DFES website) for the full set of information sheets

If you require a BAL report for your project please contact us directly.

BAL Reports WA | BAL Reports Perth

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