Colonial bars on windows -- not BAL40?

Hi all,

Here's something that highlights the confusion over the fire standards: Stegbar's told me they can supply BAL40 rated timber windows for my house, but not if they have Colonial bars (ie: glazing bars) on the glass.

Conversely, Paarhammer have said timber bars on the glass make no difference. Which I'm more inclined to believe, as the timber/glass fire certification covers any size glass pane.

The Stegbar rep can't tell me why glazing bars reduce the fire rating. Anyone have any ideas?

Cheers,
J.

Hi Johnson,

To put the construction requirements simply:

Windows on a house constructed to BAL-40 need to either:

- be protected by bushfire shutters.

or

- metal framed, totally screened and contain 6mm toughened glass.

If a company has a window system constructed of wood, then i would suggest that they have spent alot of money on testing to ensure that it meets BAL-40 requirements (IE: a radiant heat level of less than 40 kW/m).

I would suggest that in the case of Stegbar, they have not done the required testing (or they did and it didn't meet the requirements) on their wooden window systems with glazing bars. If you have fire radiating heat onto a wooden window system, the first bits that are going to give way are either the glass or the smallest wooden sections. IE: wood separating the glazing bars. This would be my suggestion why glazing bars reduce the fire rating.

G'day Johnson,

The Stegbar cedar options for BAL 40 do not need to meet the 'metal frame' criteria of AS3959 as they would have been tested using AS1530.8.1 . Any window solution passing AS1530.8.1 is deemed to comply, at a guess I would say that the testing of their product with bars was either not conducted or failed. Be aware that there are now a lot o glazing products out there meeting AS1530.8.1 making them suitable for BAL 40. Trend have a number of products that comply beyond their Xtreme range.

H.

So are there ANY windows out there that are BAL 40 with colonial bars? We are building an extension to our house, which has colonial bars on all the windows. As the extension is to the front of the house, we are keen to match new windows with the existing but have been hit with a BAL 40 rating.