Composite Decking

Do you love the look decking but are not sure if you want another ‘thing’ to maintain around the home. A few years ago I built a timber deck, it was made from pressure treated softwood. For the first year it looked and felt great, but after a winter it began to get slippery in the wet. The only way I found to avoid this was by giving it a blast with the pressure washer. It wasn’t only the slipperiness that occurred. As the decking was subjected to the elements planks began to warp – albeit only slightly. The most annoying thing thought was that the wood started to splinter. Most softwood decking has 5-8mm grooves in it to allow for water drainage and therefore prevent it becoming slippery. I found that the peaks of these would chip off and leave rough edges. Not great for walking on barefooted.

I am a fan of natural products and love working with timber, but I do not like building something that is eventually going to create me more work in the long term and rapidly deteriorate. After looking around on the net I found an alternative to the normal pressure treated timber and traditional hardwoods, there were a few companies producing something called composite decking. Composite decking is a composite of reclaimed wood fibres and polymer resins. The one aspect that I like about the composite decking material is that it uses wood fibres that would have otherwise gone to waste. But other than it’s eco friendly credentials it has a whole platter of advantages that will save you hard work and money in the long run.

Composite decking looks like real wood – it has real wood in it – but that is as far as the similarities go. It doesn’t rot like wood, it doesn’t warp like wood, and it doesn’t splinter like wood. Once installed a composite deck will not require any maintenance, just a sweep once in a while as you would any other outside surface, but in terms of staining, oiling or any other form of preservative there is nothing to do.

In the UK if you go to a timber merchant a piece of pressure treated softwood decking board is about £7.00 a meter length. If you’re a reader from the USA your prices tend to be quoted in square feet, you can expect to spend around $2.00 on a square foot of softwood pressure treated timber decking (that cost is for the deck only and not the joists that go underneath). On average a composite timber deck will cost $3.00 per square foot and in the UK about £8.00 per linear meter. So in terms of percentage increase the USA are looking at paying about 50% more than a softwood deck and the UK about 15% more. If you were thinking of building a hardwood deck then you would actually save a lot more money by going for a composited deck.

Composite decking manufacturers tend to offer 20 to 25 year guarantees on their products providing that they are installed to there specifications. Two of the biggest decking board manufacturers Trex Composite Decking and TimberTech offer a 25 year warrantees which speaks volumes about the faith they have in their products.

When you take in to account all of the decking manufacturers there is a large choice of colours and finishes. There are two main finishes, these are plain ad grooved. Neither of them get slippery when wet and so what you go for is entirely down to personal preference. The planks come all of the normal wood colours you would expect such as teak, cedar, walnut etc but because of the polymer element there is some scope to offer different colours such as black and white.

Working with composite decking is much like working with normal timber. A sub-frame should be build that supports the planks every 400 – 500 mm. The sub frame specification should be checked to individual manufacturers reccomendations. A decking plank can be sawed and drilled much like normal wood. The fastening of the planks to the sub frame is a little different though to working with normal wood. Composite decking planks have a channel that runs along the length of the sides of the planks much like tongue and groove. There are then special clips that clip into the grove and you then screw the clip into the sub frame. The diagram better show this.

There is one downside to composite decking and this is not due to its use but more to do with the construction process of it. When you are sawing and drilling the decking you will need to make sure that you collect the shavings and sawdust – they are not biodegradable. You can’t just sweep them in to the nearest flower bead… they’re going to be there a long time (more than 25 years according the manufacturers warrantee!) This is a small price to pay for an otherwise excellent system.