BAL-FZ Windows

Paarhammer recently had new BAL-FZ windows tested, well exceeding the minimum requirements of the AS1530.4 test. These are 30-minute products (-/30/-), which are allowed to be used in Flame Zone without shutters as per the 2018 Australian Standard for Building in Bushfire Prone Areas with limitations. 

Two options 

AS1530.4 products (-/30/-) can only be used in BAL-FZ without shutters if there is ‘... a minimum setback distance of 10m from the edge of the classified vegetation’.  

The Australian Standard (AS) states that ‘In circumstances where the 10m setback distance between the building and the edge of the classified vegetation cannot be achieved, those elements of the building that are less than 10m from the edge of the classified vegetation shall conform to AS1530.8.2.'

AS1530.8.2 is a different test, which Paarhammer products first passed already in 2011, being the first supplier of windows and doors for BAL-FZ bushfire attack level areas without the need for shutters. This test has a 30-minute furnace cycle and a 60-minute cooling down cycle in which the product still has to keep its integrity. Paarhammer products achieved this in addition to a very low heat flux. These products also comply with the 2018 AS.

Heat Flux

AS1530.4 test - while measuring for heat flux - the combined effect of ‘radiation and convection’ - this is not a relevant factor in this AS. Measured heat flux during the test 365mm from the unexposed side of the glazing (inside) resulted in a radiation level of almost 25 KW/m². 

AS1530.8.2 test - measured heat flux during the test 365mm from the unexposed side of the glazing (inside) reached a radiation level of 1.1 KW/m² for Paarhammer tilt & turn windows, fixed window, hinged door and French doors, and below 1.0 KW/m² on Paarhammer lift-slide sliding doors.

To put this into perspective, naked skin can tolerate 5KW/m² for approximately 10 seconds only.


If using Paarhammer products for building in a BAL-FZ area, you now have the choice of two very differently performing kinds of window and door products, tested to two different Australian Standards. Please be aware of the 10m classified vegetation rule of the 2018 AS when specifying window and door products for Flame Zone use without shutters.

A dedicated page for the newly tested and approved BAL-FZ products to AS1530.4 will be available soon. For further information please contact us.