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Decking Subframe & Joists

Composite Decking Subframe & Joists

There is not a one size fits all when it comes to a decking subframe, each project is different; where the decking will be installed on, what type of surface it will be sitting on will, this will all depend on the joists and posts needed. Whether the project is for commercial or domestic use the decking subframe is very important and our range of cost effective joists, lumbers and posts are weatherproof and great alternatives to timber.

Subframe & Supports That Offer Longevity

Hollow composite joists – made from the same material as our composite deck boards – recycled plastic and wood are a great solution when installing composite decking onto a solid foundation. Easy to install and light weight our hollow composite joists are a hassle free and cost effective solution that will last the test of time.​

Raise Your Deck

Adjustable pedestal supports – Used on a solid foundation and in areas where you require a raised deck. Our eco-friendly long-lasting adjustable pedestals are easy to install and come complete with 4-way 50mm joist cradle. These can be used with timber, plastic, metal or solid composite joists.

​Assured base slope correctors which are used to compensate the grounds slope and Assured rubber mats which absorb noise compliment the pedestal supports.

Recycled And Recyclable

Plastic lumber joists and posts – Robust, lighter and more durable than timber products available, plastic lumbers and joists are a fantastic alternative. Made using 100% recycled plastic and easy to install, plastic joists and plastic posts are ideal in situations where the ground is soft or uneven. If required plastic lumber joists fit our Assured adjustable pedestals and are great for elevated decking areas in commercial or residential environments.​

Offering a longer lasting timber joist

Decking joist tape – Our self sealing decking joist tape protects wooden subframes against water, moisture and weathering providing you a more cost effective decking subframe. They can be used on wooden decking joists, wooden joist noggins and even joists hangers to stop corrosion and once applied the decking joist tape gets stronger over time offering more protection.

Why Choose Composite?

We are the UK's leading supplier of cost effective high quality composite decking, composite cladding and composite fencing for residential and commercial projects. Our products are made to the highest possible standard and go through rigorous and in depth testing phases before, during and after manufacture. Our forward thinking experienced team deliver efficiency, quality and the best customer care at all times providing customers a hassle free end to end solution when purchasing our products.

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If you have any questions regarding our Assured Composite® ranges then please give us a call on 0166 440 0140 or email us at

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