Answers to common questions
- Composite decking review (WPC).
- What is the best decking timber type?
- What is the best decking treatment?
What is composite decking?
Is it better than timber decking?
Composite decking or wood plastic composite (WPC) is a composite of wood fibres (cellulose saw dust) and plastic. The proportion of the mixture can contain 50% to 70% wood. Wood plastic composite decking can be made of recycled plastic and wood waste but that's not always the case.
- Important advantages of composite wood are: high resistance to weather, rot, insects, no need for paint (low in maintenance), easy to handle.
- Some disadvantages are: high energy intensive production, more expensive than wood, very hot weather could cause a problematic flexibility, really not a natural product, hard to recycle.
Wood-plastic composite manufacturers claim that their composite decking is a contribution to environmental protection because it is more durable than timber and doesn’t need any preservatives. Fact is however that this synthetic decking timber can still absorb water because of its high content of cellulose. And that appears to be a problem, so manufacturers are trying to improve the characteristics of plastic composite decking by treating it with preservatives and chemicals.
Manufacturers also say their synthetic decking is 100% organic and it preserves the woods because of the use of recycled resources and thus avoiding deforestation. Deforestation is actually more a mismanagement of forests and it is also known that not all wood-plastic composite products are made of recycled resources. The other question is whether forests can be protected in the long run by not using wood at all or if particularly the sustainable utilisation of wood helps to conserve forests.
According to WPC manufacturers, composite decking is 100% recyclable. It may be true however, it is surely very difficult. Composite wood is a compound of an organic and a synthetic material and that is always hard to recycle. I can’t think of any product made of recycled composite wood.
Since we are a deck building company, we have no financial interest in promoting either composite decking or real timber. The main reason for building composite decks is the low maintenance effort. However, the entire structure is not necessarily more long-lasting if the support beams are made of ordinary timber.