
Alternate Dwellings - Australian Timber Modular Kit Homes, Homesteads, Cottages & Cabins
Alternate Dwellings - Australian Timber Modular Kit Homes, Homesteads, Cottages & CabinsTo understand the whole BAL Assessment process better, I’ll outline how we were instructed to assess a property.
The Fire Danger Index (FDI) is a measure of the probability of a bushfire starting. This factors, amongst other things, the rate of spread, intensity and difficulty of suppression according to various combinations of temperature, relative humidity, estimate of fuel state and so on.
The Australian Standard AS 3959-2009 identifies the FDI for all regions across Australia.
The Australian Standard AS 3959-2009 provides tables that set out visually and descriptively, seven types of vegetation classification.
After determining your site’s vegetation type, the next step is to determine the distance from your site to the vegetation itself. This is because the proximity of the vegetation to the building site will have an influence on the level of bushfire risk.
The slope of the land towards the vegetation has a direct influence on the severity of abushfire. Bushfires have a tendency to move uphill more rapidly than downhill.
To determine the BAL one enters the Fire Danger Index (FDI), vegetation types, distances and slopes into a given table in the Australian Standard AS 3959-2009.
Now you can apply the construction requirements as set out in the Australian Standard AS 3959-2009 that correspond to the BAL that you have determined.