What Are The Best Joists For Composite Decking?

Any good build starts with strong foundations and that goes for laying your composite decking too.

There’s no denying composite boards look great and a quick internet search will extol the many virtues of this product. Strong, durable, low maintenance and cost effective, to name just a few! But, as with any project, to fully benefit from these attractive features it’s essential to get the basics right. And that starts with your subframe.

Yes, composite decking doesn’t require complicated foundations like some constructions – no concrete or extensive additional work needed here. But you do need to get it right and create a sturdy joist frame to act as your decking support.

So how do you go about it? To help, here we establish the best joists to use for composite decking and take a look at other key factors worth considering to ensure the safety and longevity of your composite decking.

What is a joist?

Floor joists are used as a way of supporting a floor. They provide a frame for decking to be attached too and offer structural stability and strength. 

The joists you use will provide the backbone to your decking area, helping to ensure it is fit for purpose and safe to use. So, although the framework will ultimately be out of sight, the support for your composite decking should never be out of mind and deserves due consideration from the outset.   

Knowing what joist to use can be tricky, there are a number of things to take into consideration. These include:

• The material you are using – frameworks can be built from a number of materials, such as traditional timber. You can also use composite decking for your frame.

• The height of your frame – how far off the ground your deck will sit also has an impact on the material used, with composite decking offering excellent resistance to rot. If you opt for regular timber for your joists be sure to check it is pressure treated.

• The spacing of your joists – this is a really important point. Allow too much space between the centre of one joist and the next and the structure will be too flimsy and weak. At Modern Garden, we recommend using 40cm centre spacing.

• The thickness of your joists – this obviously depends on the material you have decided to use to build your subframe but, the thicker the joist, invariably, the stronger it is.

Before you start building your frame remember that your joists should run perpendicular to the direction you want your decking boards to run. This is important as it increases strength and stability…and isn’t something you want to learn once you’ve finished your frame!

At Modern Garden, we specialise in composite materials and offer high quality decking to really add life to your living space. Graphite, dove grey, driftwood – whatever look you prefer, we offer a decking range to match. Why not view the collection now?

For more tips on how to lay composite decking, check out our installation guide – or talk to one of the team. You can call us on 01695 557711 or email info@modern-garden.co.uk. 

And don’t forget – for a truly professional job from start to finish – we also offer a variety of decking accessories too. Browse our composite trims and fixings and add them to your order.