Adding biowood to fire in cladding disasters
What is cladding?
Cladding is often used to make a building's exterior look more attractive. The term 'cladding' refers to components that are attached to the primary structure of a building to form non-structural, external surfaces. This is as opposed to buildings in which the external surfaces are formed by structural elements, such as masonry walls, or applied surfaces such as render.
Whilst cladding is generally attached to the structure of the building, it typically does not contribute to its stability. However, cladding does play a structural role, transferring wind loads, impact loads, snow loads and its own self-weight back to the structural framework. Cladding can also provide sound and thermal insulation as well as fire resistance.
What is cladding made from?
Wood, metal, brick, vinyl, glass, composite materials that can include aluminium, wood, blends of cement and recycled polystyrene, wheat/rice straw fibres.
Latest development in the area of cladding – Biowood cladding
Just when everyone thought that there was a thorough understanding on what type of cladding is considered non-compliant because it is combustible, in 2019 the NSW Civil and Administrative Tribunal handed down its decision of The Owners Strata Plan No 92888 v Taylor Constructions Group Pty Ltd and Frasers Putney Pty Ltd. This dispute did not involve the ill-reputed aluminium composite panels that were declared as being highly combustible and caused the Victorian Government to create the organisation "Cladding Safety Victoria". Rather, this matter considered proprietary architectural product called Biowood.
If you are not familiar with this product, just picture McDonalds with its wood-like façade. Biowood consists of at least 70% of pulped wood and 23% of polyvinyl chloride (PVC). It has been marketed as a safe product, to be used for private screening, balconies and façade. The NSW Tribunal however, decided that this material, when installed on the façade of the building poses an unacceptable risk of spreading fire.
The Owners Strata Plan No 92888 (the Applicant) argued that the Biowood cladding installed as an embellishment on the external walls of the building is a defect, as it is combustible. In support of its argument, the Applicant referred to Clause 2.4 of the Building Code of Australia (BCA), Specification C1.1, and stated that the installation of the combustible material is a breach of statutory warranties contained in Section 18B(1) of the Home Building Act 1989 (NSW) – the equivalent of the Victorian section 8 of the Domestic Building Contracts Act 1995 (Vic).
The Applicant successfully defeated the Respondents' argument that the material is compliant with the relevant Australian Standard (AS/NZS 1530.3) and stated that the composite panels in the Lacrosse building complied with the same Standard however, proved to be highly flammable when subjected to the full scale of fire.
The Tribunal accepted the expert opinion given by CSIRO for the Applicant that the AS/NZS 1530.3 is not applicable to the materials used for the external attachments, wall lining and cladding. It held that the Respondents breached the statutory warranties and decided that "any risk of fire spread is sufficient to satisfy the measure of undue risk".
What are the repercussions of the above decision?
If you want to purchase a property, particularly a unit with cladding, engage an expert to inspect your prospective purchase with a specific emphasis on the cladding type.
If you are a builder, you need to ensure that you examine specifications that you are given by the owner (or a developer) and ensure that the cladding is not combustible. You, as a builder, will be held liable for breach of warranties in respect to the suitability of the product that you install, in line with the Owners Corporation No.1 of PS613436T v LU Simon Builders Pty Ltd (Lacrosse Tower) decision and ordered to pay the full amount claimed by the owners. You will be however, able to apportion the liability to the professionals, who design and certify the project and construction (i.e. the architect, fire engineer and the building surveyor), in full or almost in full – again, in accordance with the Lacrosse Tower decision, when the liability was allocated as follows:
- the Building Surveyor: 33%
- the Architect who specified the type of cladding: 25%
- the Fire Engineer: 39%
If you are a professional in any of the above categories, ensure that you research products that meet the current BCA standards before finalising your design and/or before you sign off on any compliance certification.