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Installing Assured Adjustable Pedestal Supports & Joists

Composite Decking Pedestals Help Support The Deck

We advise using Assured Adjustable Pedestal Supports on a concrete or solid foundation and creating a decline of 1% – 1.5% away from a property acting as a drainage slope.​

Laying The Decking Pedestals

Starting from the edge of the decking area, place the decking pedestals width ways in a gridline format leaving a 300mm max interval between each decking pedestal centre. Spacing between the decking pedestals length ways will depend on the thickness of the joists. If Assured Adjustable Base Slope Correctors are used then simply sit the decking pedestals on top of the base slope correctors where required. If Assured Pedestal Rubber Mats are used then sit these underneath the decking pedestals and base slope correctors where required.

  • 50x50mm Joist: 500mm max intervals
  • 50x100mm Joist: 750mm max intervals
  • 50x125mm Joist: 750mm max intervals
  • 50x150mm Joist: 750mm max intervals

Rotate the decking pedestal base clockwise or anti-clockwise to set the required height for the deck checking heights from one decking pedestal to another with a spirit level.

​Decking pedestals and base slope correctors can be fixed through the base if required. Ensure the area is clear and free of any obstacles including any cables and pipes.​ In most cases the weight of the joists and deck boards will hold them into place. We do not advise fixing decking pedestals or base slope correctors to a roof terrace.

Laying The Joists Onto The Decking Pedestals

Measure and cut the joists where required.

Lay the joists through each decking pedestal joist cradle. Allow a 20mm expansion gap between joist butt joins and use a 300mm cross member for support. Fix into place by screwing joist and cross member together.

Fix the joists to the decking pedestals by screwing through the joist cradle.

Double joist where deck boards meet at butt joins allowing 3mm between joists.​

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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