Share with
Fire resistance is such an important topic and one that we take seriously here at Stramit. It’s important for everyone in our building industry, including product manufacturers, architects, builders, engineers and installers.
The National Construction Code (NCC) sets out technical provisions for the design, construction and performance of buildings throughout Australia, which include criteria for the assessment of building elements under fire conditions.
Part C1 of Volume One of the NCC 2019 states the provisions that need to be met for fire resistance and stability when proposing a Deemed to Satisfy solution. As stated in Part C1.9, building elements in certain types of fire resisting construction, for example external or common walls, load bearing internal walls etc, must have all components that are non-combustible. Stramit® wall sheeting used in this type of construction must meet this requirement. Part C1.9(e) gives a list of materials that may be used where non-combustible components are required. One option is metal sheeting with a combustible surface finish less than 1mm in thickness, with a Spread of Flame Index not exceeding 0.
Similarly, in Volume Two of the NCC 2019, Part 3.7 sets out the requirements for Fire Safety, and Part 3.7.1 states the Fire properties for materials and construction. The Acceptable Construction Practice includes a section 3.7.1.1 on General concessions – non-combustible materials. One of the options mentioned here as non-combustible is metal sheeting with a combustible surface finish less than 1mm in thickness, with a Spread of Flame Index not exceeding 0.
Stramit® roofing, cladding, rainwater and structural building products are manufactured from steel produced by Bluescope® Steel or Pacific Coil Coaters (through Selection Steel). Both organisations have had independent tests on their materials carried out by CSIRO or AWTA. The testing was conducted in accordance with the Australian Standard AS1530.3 ‘Simultaneous Determination of Ignitability, Flame Propagation, Heat Release and Smoke Release.’ All materials had a surface finish less than 1mm in thickness and a Spread of Flame Index of 0. More detail is given in the table below.
Steel Source |
Base Metal Thickness (mm) |
Finish |
Certificate Number |
Ignitability Index (0-20) |
Spread of Flame Index (0-10) |
Heat Evolved Index (0-10) |
Smoke Developed Index (0-10) |
Bluescope |
0.35 |
Colorbond® |
FNE11605 |
0 |
0 |
0 |
2 |
Bluescope |
0.7 |
Colorbond® Metallic |
FNE11604 |
0 |
0 |
0 |
2 |
Bluescope |
0.42 |
Zincalume® |
FNE11602 |
0 |
0 |
0 |
2 |
Bluescope |
0.42 |
Truecore® |
FNE11601 |
0 |
0 |
0 |
1 |
Bluescope |
0.42 |
Galvanised |
FNE11600 |
0 |
0 |
0 |
2 |
Bluescope |
0.55 |
PVDF |
FNE11606 |
0 |
0 |
0 |
1 |
Pacific Coil Coaters |
0.42 |
Magnaflow |
19-002186 |
0 |
0 |
0 |
3 |
CONCLUSION
Stramit® products made from these steel sources and with the tested finishes would be considered non-combustible according to NCC 2019 Volume One Part C1.9(e) and Volume Two Part 3.7.1.1.
It is important to note that Stramit® sheeting is only one component used in construction of these building elements, and other components must also meet the necessary requirements to satisfy the criteria.
For information on performance of residences in a bushfire situation, please refer to the bulletin based on the NASH Bushfire Standard on the Bluescope® website.
For further information about our products including their fire resistance, please contact our Technical Services team at techsupport@stramit.com.au or on: