Timber can be used internally in all BAL zones. The external use of timber requires more care and planning, especially on higher BAL rated sites.
The documents linked to on this page provide more information.
You'll also find Q&A about building in bushfire prone areas by searching the Q&A database in the Expert Advice pages
The following Technical Design Guide is available for download:
Download a range of fire test reports relating to building in Bushfire prone areas.