Technical Data

Composite Decking Technical Data:

UK Composite Decking Technical Data overview: Ecodek® composite decking is a mixture of hardwood fibres (approximately 55%) and high density polyethylene with the addition of certain additives to improve physical, weathering and processing properties.

Composite Decking Installation Ingredients

The polyethylene used in this product is a high quality, recycled material made up of mainly bottle, film and pipe materials. The hardwood fibres are also a recovered material which are processed, filtered and dried before being compounded with the polyethylene. The resulting product is 90-96% recycled and 100% recyclable.

UK Composite Decking has many useful properties when used as decking, these include:

  • Low moisture absorption
  • No rotting, splintering or splitting
  • In-built termite and UV resistance
  • Excellent dimensional stability
  • Slip resistant surface in the wet and dry (tested to HSE standards)
  • No toxic materials to leach into the soil
  • Easy as wood to work with

Composite Decking Technical Data

Application Data:

UK Composite Decking 25mm x 136mm profiles are well suited for use as decking, fencing, pool sides, marinas and other similar applications. They may also be used as a replacement for wood in many other areas where a non-load bearing support or structure is required.

The other profiles in the range can be used for fencing, railings, cladding, garden edging and post & rail projects to name but a few. UK Composite Decking profiles are best suited for outdoor applications where the product’s inherent advantages over wood can be exploited as fully as possible.

UK Composite Decking Installation Instructions:

More detailed instruction is included in our ‘Quick Installation Guide for Installers – Data Sheet 1’.

It is vital that you read this data sheet before commencing any UK Composite Decking installation. Use the same tools used for timber to fabricate and install UK Composite Decking decking products.

With the 25mm x 136mm deck boards, support frame joists must be spaced on maximum centres of 455mm (18”) or less for residential decks, 405mm (16”) or less for commercial applications.

When laying the timbers at 45 degrees to the support frame the joists should be spaced on centres of 330mm (13”) or less (300mm or less for commercial applications).

Boards should not overhang the joists by more than 40mm.
(If using the 24mm x 95mm deckboard, joist centres should be 355mm (14”) max and 255mm (10”) if fitting diagonally.)

When butting boards end to end, this must be done over a double width bearer to ensure both composite boards are sufficiently fastened down. Screw holes must be pre-drilled (to prevent splitting) at least 20mm, and not more than 40mm in from the cut edge. Deck boards must span at least 3 bearers in order to give the board the load bearing properties stated in our literature and to eliminate the possibility of sagging over time.

For optimum water drainage and to allow for proper ventilation, a gap of 5mm must be left in-between the boards and a minimum 5mm gap at the cut ends of the boards (for hot, humid or damp areas, a 10mm gap is required between the cut end of the board and any walls).

Failure to do so will promote the growth of mildew and prevent moisture evaporation, these gaps will also allow for material expansion in hot weather.

Good airflow under the deck is vital to prevent moisture remaining for long periods on the underside of the boards, poor airflow will invalidate the warranty.

Only use screws designed for composite decking, normal timber decking screws are not strong enough and will invalidate the UK Composite Decking warranty. We supply a stainless screw specifically designed for Composite Decking. It is available in a range of colours to match the decking. Use 2 screws per joist/bearer (if using 50mm screws, then 3 screws per joist).

Always pre-drill before screwing down the board, we recommend using a SMART-BIT® for fast & easy drilling (available from UK Composite Decking).

Never leave the end of the board unrestrained, it must be pre-drilled & screwed down within 20-40mm of the cut end. The screw head should sit flush with the bottom of the groove (or decking surface if using a smooth board).

Do not use fasteners within 18 mm of the side of the board. (The rule of thumb is to screw into the second groove on each side of the board if using the grooved side.)

NB: If using the 38mm x 88mm sub-structure profile (i.e. as a joist), it must be noted that it needs more support than with a softwood equivalent. We recommend either laying the substructure profile directly on the surface to be built upon, or supporting it on posts but with a maximum span of 1 metre between post supports, secondly, there must never be more than 100mm overhang at the end of the substructure profile. It must also be noted that when screwing composite to composite, the screw pilot holes must be 3.5mm dia