Frame and sub structure for composite decking

Joist spacing for composite decking requirements

A deck is only as strong as its sub-structure. As such ensuring you use quality joists that are correctly installed is crucial for a long-lasting, safe deck.

What is joist spacing?

Joint spacing is the distance between each joist located underneath your deck. This distance will differ for each deck, depending on its size, shape, and weight.

Why is it so important?

Your composite decking is supported by joists, and it is these joists that ensure your deck remains solid, safe, and structurally sound. As such their correct installation is imperative.

How far should your support spacing for composite decking be?

This will depend on the size of your decking and the composite decking boards you choose. For example, our Low Profile support joists should be fitted at no more than 500mm intervals, whilst our Super Stiff joists at no more than 1,000mm intervals.

Following the manufacturers instructions with regards to the installation of your joists will ensure they are fitted correctly and – as well as your deck – will last for many years to come.

What is the best composite deck span for Ecodek products?

As mentioned above, the best distance apart for your joists will depend on the make of your chosen decking and its size.

If you would like further guidance on how best to install your support joists, contact our expert team today on 01978 667 840 for a no obligation chat.


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