How to install composite decking  –  A guide to assist with installation


At New Wave Flooring, we provide a wide range of composite decking options, we also provide a guide to assist with the installation of your composite decking, please find below:

HANDLING

Compared with timber decking, composite decking has a higher specific density and is heavier. Please be careful when transporting and handling eco decking. When storing and stacking plastic decking prior to installation, be sure to place on a flat surface.

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Distance between Joists

Preparation is the key to any successful composite decking installation. You need to create a solid platform for the decking boards to be attached to using the clips and screws provided. To do this you will need to dig holes for the stumps, attach the bearers to the stumps and then attach joists to these bearers in order to have a solid base for the composite decking boards to be attached to.

  • Our 138mm x 23mm hollow composite decking boards that the distance between each joist be no more than 400mm.
  • Our 138mm x 20mm solid composite decking boards that the distance between each joist be no more than 400mm.
  • Our 140mm x 20mm solid composite decking boards that the distance between each joist be no more than 400mm.
  • Our 120mm x 20mm hollow composite decking boards that the distance between each joist be no more than 200mm.

TOOLS

Standard carpentry tools will be required such as; power saw, string lines, level, screwdriver, hammer, drill, post hole digging tools etc will be required.

Preparing the foundation

A solid foundation for the successful installation of any of our composite decking boards is vital. Using a string line (or other device) mark out the desired positions for the holes for the stumps, dig the holes and set the stumps in a concrete footing in preparation for the bearers to be attached. It may be appropriate to allow 24 hours for the concrete footings to cure.

Joists

Once you have constructed the sub floor bearers you need to attach joists ensuring the distance between the joists adheres to the guide above depending upon which type of decking board you have chosen. Screws or fixings used in the installation should be of zinc, stainless steel or galvanised variety to ensure they do not rust.

Please note; composite decking is not suitable to use as structural components for any buildings. Do not fix composite decking directly on any solid surface or water-tight system, such as concrete, rooftop or balcony, etc.

You must leave enough gap when installing composite decking boards to allow for thermal expansion and contraction. This is necessary not only when laying the boards end to end but also between the boards. End-to-end, width-to-width and end-to-width. Gapping is necessary to allow for drainage and the slight thermal expansion and contraction of composite decking boards.5 Allowing for Thermal Expansion (Gapping)

  • Width-to-Width: The general width-to width gapping is 2-5mm.the gapping in-between decking by clip is determined by the clip size.
  • End-to-End: The general end-to-end gap is determined by a number of factors, the length of the composite decking boards being installed, the temperature at installation, the co-efficient of thermal expansion/contraction, the highest temperature expected during the year and whether the boards are exposed to full sun and/or shade. Expansion could be as much as 10mm at either end of the decking board depending upon the factors mentioned above.
  • End-to-Width: The general end-to-width gap is determined by a number of factors, the length of the composite decking boards being installed adjacent to a longitudinal composite decking board, the temperature at installation, the co-efficient of thermal expansion/contraction, the highest temperature expected during the year and whether the boards are exposed to full sun and/or shade. Expansion could be as much as 10mm on the decking board depending upon the factors mentioned above.

Design the patterns


Due to the expansion and shrinkage, the patterns of composite decking design are different from real decking patterns.

patterns we recommended with joins

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patterns we don’t recommend for composite decking:

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How to install composite decking – A guide to assist with installation


Once the sub-framework and pattern design are finished, you can start laying your composite decking.

Step 1  Install bullnose edging board

Secure the bullnose clips on the joist one meter apart, push the bullnose board in and use the decking clips to secure the other side of the bullnose board.

Please note: leave at lease 22mm hangover on the bullnose side if you are going to install a facial board under.

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Step 2  Install facial board if needed

You can use the same composite decking board as a facial board, simply screw the board directly to the frame, the top groove can be hidden by the bullnose board edge

Step 3  Install the composite decking

Put the decking clips we provided on each joist and drill the screws approx 80% in, then push the sec board in and tighten the screws up. Repeat the same process for the rest boards.

Please note: you don’t have to put the screws super tight because it might be pulled out when the board moves

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Step 4  leave a gap

As explained above, composite decking will have movements when the temperatures are up and down, make sure to leave a gap on each side of the board to give it space of expansion. Check out the temperature you are installing the decking and decide how much gap you need.

Check out the temperature when you are installing the deck and decide how much gap you need to leave:

For a 5.4m full length

leave 3mm on each end when the outside temperature is 30 degrees, 

leave 5mm on each end when  the outside temperature is 20 degrees,

leave 7mm on each end when  the outside temperature is 10 degrees,

Step 5   Install the last board and job finish

The clips won’t work on the last end of the board, especially against a wall. To secure that, pilot a hole on the deck and put the screw directly through the decking board.