WPC (Wood Plastic Composite) boards are fire resistant to a certain degree, but not completely fireproof. WPC boards are made from a mixture of wood fibers and plastic, and the wood component of WPCs is combustible. However, WPC boards are typically treated with fire retardants to reduce their flammability.

Fire-resistant comparison between WPC boards and wood

General experience shows that WPCs have a fire behavior very similar to, or better than that of comparable timber products.

Fire tests relate to either flammability or ignitability which considers the ease with which a material will catch fire and sustain burning and “spread of flame” which considers the propagation of fire by the material being tested.

Most of the fire testing of WPCs has been carried out ASTM standards in USA and EN standards in European. Their test methods are similar.

As a general rule, the presence of the plastic matrix appears to improve the fire performance of the wood component in WPCs. Many plastics, e.g. PVC-U, HDPE, etc. have good ignitability and spread of flame performance and this appears to be transferred to the WPC when they are used as the plastic component.

WPC boards show good results in ignitability tests and these are similar to the results for wood with similar density.

WPC boards show good results in spread of flame testing and the results can actually be better that those of wood with a similar density.

Enhancing Fire Performance of WPC Boards

The fire performance of WPC boards can be modified and improved by the addition of flame and smoke retardants to the raw material before processing. The fire-retardant properties of WPC boards have been enhanced by adding halogen-free fire retardants to the wood-polymer mixture during the melt phase.

Some WPC manufacturers offer specialized fire-proof formula products that can achieve a Class A rating under the ASTM E84018 standard, highlighting the potential to deliver enhanced fire-resistance properties.

It is important to note that no building material is completely fireproof. Even WPC boards with a Class A fire rating can ignite and burn if exposed to a high enough heat source. However, WPC boards with a Class A fire rating will resist fire for a longer period of time than WPC boards with a lower fire rating.

It’s essential to acknowledge that while WPCs generally exhibit commendable fire performance, the flammability factor remains significant in specific construction applications. Therefore, it is imperative to always implement appropriate fire safety measures when employing WPCs in construction projects.

For detailed insights and deeper understanding, refer to the following sources:

Understanding the fire behavior of WPCs allows for more informed decision-making in construction, ensuring both safety and optimal performance in diverse building applications.

Bongywood Wood Plastic Composite

Guangdong Bangying New Building Materials Co., Ltd. is a professional manufacturer specializing in the R&D, production, and sales of WPC (Wood Plastic Composite) materials, our products include composite decking, capped composite decking, WPC Wall Panel, WPC Railing & Fencing, WPC Pergola & Gazebo, WPC Chairs & Bench, WPC Flower Planter Pots, etc.


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