Is Composite Decking Waterproof?

So, your timber deck has seen better days, you’ve long given up trying to scrub the algae off, staining and painting, and the edges are starting to show signs of decay. At this point, you can either replace with the same again or find a different solution.

When considering a replacement for your rotting deck, the obvious choice is a non-timber alternative. However, when evaluating your options the simple question arises, is there such a thing as waterproof composite decking?

The simple answer is no. The only decking option which can offer 100% protection against moisture absorption is plastic. The trouble with plastic is that it can become brittle when exposed to extreme temperatures and is often sold as boards that are virtually hollow, offering very little rigidity or robustness for supporting medium to high volume traffic, furniture or hot tubs.

Composite decking resists moisture due to its material makeup. Timber rots because it absorbs a lot of water. Wood rot occurs through decay, triggered by a combination of moisture and fungus growth. Unfortunately, this makes timber and the outdoors unhappy bedfellows.

Timber, by design, collects water. It grows within a tree by channelling water from the roots through the tips of each branch to fuel growth. Once a tree is felled, the timber continues to absorb water but has no outlet through which to channel it. Ultimately, this results in decay.

By comparison, NeoTimber’s composite decking absorbs very little moisture, being made of a combination of 30% recycled plastic and recycled wood fibres. Our capped composite deck boards, specially engineered to fend off moisture, have a water absorption rate of 0.13%. Even our traditional composite deck boards only allows up to 0.65% moisture absorption… Not quite waterproof decking, but nearly.

NeoTimber® is, as the name suggests, ‘new timber’. Timber which has been re-engineered to fend off the worst that the weather can throw at it. Whilst still looking very much like ordinary timber, Wood polymer composite decking, or WPC decking as it is sometimes known, arms timber against wood rot by fusing together wood fibres and plastic elements. These two disparate elements work together but independently to flex, breathe and resist moisture, resulting in a stronger, more durable material. It is for this reason that NeoTimber® feel so confident about their products, and so we offer a 25-year residential warranty.

If you’re currently looking into changing your decking, please contact us or look at our pricing calculator to find out how much it would cost for you to transform your garden with a no-maintenance deck that you can enjoy all year-round.