Is Composite Decking Fireproof?

The Grenfell Tower fire was a tragic event in 2017 that resulted in the loss of 72 lives from an uncontrollable blaze at a high-rise tower block in Kensington, West London. The inquiry and subsequent fallout from the disaster have highlighted the importance of using the correct building materials when designing new high-rise buildings and cladding existing high-rise developments.

Considering this, many consumers are, understandably keen to gain reassurance on the materials that they specify for their project. In choosing what to buy, both contractors and consumers are searching for fire-rated composite decking, leading to building material manufacturers being forced to evaluate the material content and design of their material.

The question is, is composite decking fireproof? The reality is, the vast majority of man-made cladding and decking does have some contribution to fire. However, there are occasions when composite decking can be used in a new development, and knowing when and how to use it could be the difference between creating a safe development, or not.

NeoTimber® are committed to the ultimate safety of our customers and clients. NeoTimber® composite decking is manufactured using 70% recycled wood fibres and 30% recycled plastic. Timber is often classified as D-Class fire rated; these types of fires involve a solid fuel source.

However, because of the plastic element in composite decking, it is classified as a C-Class fire rating. C-Class fires involve flammable gasses such as butane or propane. Ethylene is another such gas that exists within the plastic and is flammable. This means that once alight, there is a level of contribution to fire.

What this means, in practice, is that NeoTimber® is only suitable for low-rise developments. Low-rise is classified as dwellings or developments of three stories or less. Whilst composite decking offers a low maintenance, aesthetically pleasing, material for balconies, it simply isn’t ‘building regulations’ safe to use on a high-rise.

The truth is no composite decking is completely fireproof. The material make-up of the product makes total fire retardancy impossible. Whilst some Class-B fire-rated materials exist, the fire treatment often affects the performance, quality, and finish of the material.

Work is underway at NeoTimber® to find new fire-retardant alternatives for high-rise developments, including aluminium decking but as yet, these are still in development.