AUST – Hendry advise that the Building Code of Australia (BCA) in Part C3 ‘Protection of Openings’, nominates fire windows under Clause 3.4 ‘Acceptable methods of protection’. This clause allows for the use of windows as an acceptable method of fire protection in walls requiring a FRL. The requirement for protection of window openings under the Building Code of Australia is to protect life and property from the risk of flame and heat transmission.
This article explains the parameters under the Building Code of Australia that allow fire windows to be nominated in building works.
Building Code of Australia Clause C3.4 (Fire Windows)
Acceptable methods of construction for fire windows in nominated in Clause 3.4, part extract of this clause follows:
C3.4 Acceptable methods of protection
(a) Where protection is required, doorways, windows and other openings must be protected as follows:
(ii) Windows —
(A) internal or external wall-wetting sprinklers as appropriate used with windows that are automatic closing or permanently fixed in the closed position; or
(B) –/60/– fire windows that are automatic closing or permanently fixed in the closed position; or
(C) –/60/– automatic closing fire shutters.
Building Code of Australia Specification C3.4 Fire Doors, Smoke Doors, Fire Windows and Shutters specifies fire windows to be identical in construction with a prototype achieving the required fire-resistance level (FRL), A part extract of Specification C3.4 which covers fire windows, follows:
Fire Doors, Smoke Doors, Fire Windows and Shutters
This Specification sets out requirements for the construction of fire doors, smoke doors, fire windows and fire shutters.
5. Fire Windows
A required fire window must be—
(a) identical in construction with a prototype that has achieved the required FRL; and
(b) installed in the same manner and in an opening that is not larger than the tested prototype.
Specification A2.4 Fire Hazard Properties sets out the procedures for determining the fire hazard properties (e.g. FRL) which applies to fire windows. A part extract of Specification A2.4 follows:
Fire Hazard Properties
This Specification sets out the procedures for—
(a) determining the fire hazard properties of assemblies tested to AS/NZS 1530.3; and
(b) predicting a material’s group number and smoke growth rate index (SMOGRARC) for the purposes of Specification C1.10a.
The Building Code of Australia in Specification A1.3 ‘Documents Adopted by Reference’ affecting fire windows are:
- AS 1530.4-2005 ‘Methods for the tests on building materials, components and structures – Fire-resistance tests of elements of construction’
- AS/NZS 1530.3:1999 ‘Methods for fire tests on building materials, components and structures – Simultaneous determination of ignitability, flame propagation, head release and smoke release’.
The Building Code of Australia allows for the use of Fire windows in a number of clauses, these are:
- C3.8 Openings in fire-isolated exits
- C3.11 Bounding construction: Class 2, 3 and 4 buildings
- D1.7 Travel via fire-isolated exists; and
- D1.8 External stairways or ramps in lieu of fire isolated exits
The installation of fire windows must be specified to the approved prototype under the standard fire test.