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Lawsons are the largest independent timber, building & fencing merchants in London and the South East of England. Established in 1921 Lawsons now have a number of branches offering the complete range of building materials.

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How to Install Composite Decking

How to Install Composite Decking

Composite decking is the low-maintenance alternative to timber – you don’t need to sand and seal your deck regularly and you can even still enjoy the look of timber, depending which type of decking boards you go for. You can install your new deck yourself if you’re relatively comfortable with DIY – it’s a great project for sunny days in the garden.

  1. Let your decking adjust to the conditions – don’t install your decking as soon as it’s delivered. It’s best to leave it in your garden for a few days so that they adjust to the local conditions and moisture. Make sure it is covered though if it’s raining, and try to avoid installations on cold days.
  2. Create a supporting structure – composite decking has a little more flex to it than timber and cannot support as much weight. This means that your joists should be a little closer together – never space them more than 400mm apart. Your concrete base should be at least 10cm thick and your joists need to be at least 15mm from other objects (such as walls). Make sure that your concrete has properly set before continuing and double check that your joists are level before proceeding to the next stage. 
  3. Fix your decking to the joists – composite decking is extremely easy to install and just slots together using clips or slots. Start working from the outside of your decking and make sure to screw each board down to the joist properly. You should leave a gap of at least 7mm in between boards for drainage and expansion.
  4. Finish your deck with skirting and corner trims, leaving 8mm in between them for expansion again. It’s best to avoid closing your decking off entirely so that air can circulate and water can drain more easily during heavy rains.
  5. Put out a deck chair and have a drink on your new deck.