We can determine the chemical composition and indicative fire performance for any cladding materials used on a building’s external facade. This process involves identifying and collecting cladding material samples, followed by combustibility testing. Test results are used to assess if the fire performance of the external facade will negatively impact the buildings fire strategy, and for making appropriate recommendations in the building fire safety risk assessment report.
Sampling and Combustibility Testing
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- Review as-constructed documentation
- Collect cladding material samples
- Perform testing and analysis
Review As-Constructed Documentation
We review as-constructed drawings, manufacturer’s data sheets, facade specifications and fire engineering reports which may be available. These documents will provide a background of specified cladding products and insulation materials which will assist with on-site visual inspection and identification of possible product substitution.
Collect Cladding Material Samples
The external facades of modern buildings can have complex cladding systems which are generally constructed from numerous component parts. So prior to taking samples, buildings are visually surveyed to identify suitable locations for where selected cladding material samples will be collected. Once sample locations are identified and agreed with building owners, work plans and risk assessments for the removal of samples are completed. Small core samples are then taken for the cladding surface panel, plus backing insulation and/or sarking material.
The required number of samples will be a factor of visual variations between panels, the extent of coverage, and if the building was constructed over different stages. This is defined by the building grouping assignment guide below:
| Building Grouping Assignment | Sample Range | |
| Low-rise building and/or minor size building complex | Elevation = 1-2 storeys (above ground) Footprint = <2,000m2 in floor area |
2-6 samples |
| Mid-rise building and/or moderate size building complex |
Elevation = 3-9 storeys (above ground) Footprint = >2,000m2 and <10,000m2 in floor area |
6-10 samples |
| High-rise building and/or major size building complex |
Elevation = 10 or more storeys (above ground) Footprint = >10,000m2 in floor area |
10-15 samples |
Sampling work is carefully performed so that minimal damage is made to the surrounding facade, and the resultant core hole is plugged and sealed to maintain weatherproofing of the facade.
Where access for sample collection is difficult, we will provide teams specially trained in industrial rope access techniques (abseiling). This ensures representative samples can be collected across the building
Perform Testing And Analysis
We organise for cladding material samples to undergo testing with our laboratory service partners, using standard equipment and analytical techniques, and in alignment with how Government buildings are being tested. This is a relatively non-invasive and cost-effective process which involves a set of tests to identify the cladding materials chemical composition and to assess its thermal degradation.
| Test Method and Result |
| Thermo-Gravimetric Analysis (TGA) or, equivalently, Simultaneous Thermal Analysis (STA) will be applied to determine the faction of mass loss at different temperatures and the residue nature and content after pyrolysis (organic/inorganic) |
| Fourier Transform Infrared Spectroscopy (FTIR) will be applied to determine the polymer compounds and quantities |
| X-Ray Fluorescence (XRF) will be applied to provide an elemental profile of mineral filler and fire retardant compounds |
Using the laboratory test report, our fire engineers are able to analyse the cladding’s fire risk potential.
While small scale laboratory screening testing is preferred to characterise the cladding material chemical composition and fire risk evaluation, large scale facade testing can also be organised if requested, although the cost, timeframe and complexity to set-up are this testing is likely to reduce the perceived advantages.
