Don’t make these 6 common decking installation mistakes!

common decking installation mistakes!

Don’t make these 6 common decking installation mistakes. By reading this informative copy on composite decking installation you may self yourself falling short when installing.


Composite decking is installed differently to traditional timber decking. Our Composite Decking like all composites expands in warmer weather and contracts in cooler weather. With correct installation you will achieve great looking results.

Let the boards acclimatise before cutting and laying
Boards stacked in a pack can be very different temperature than the ambient air temperature. Open the pack and lay the boards out to allow them to settle to the ambient air temperature

Allow the required gaps for expansion and contraction
Learn what gaps to use. Gaps are required at ends of all boards and also require a 12mm gap from another structure such as the house, retaining wall, pool coping etc.

There is a rule of thumb for expansion and contraction but your required gap depends on what your extreme temperatures you experience in your area. The less temperature variation, the less expansion and contraction.

Cold = 0-10 Gap required 5-6mm
Warm = 10-20 Gap required 3-4mm
Hot = 20-30 Gap required 2-3mm

Ensure the deck has adequate ventilation
Our decking is very resistant to moisture, however prolonged exposure to moisture will affect the substructure, decking boards and promote mould growth on your deck. As mentioned above, decking boards require a 12mm gap from another structure to avoid capillary action and for water to drain away. Decking boards must never be in contact with the ground or another surface except for the substructure. Use ventilation grates if necessary to allow airflow for decks very low to the ground or membrane. Common decking installation mistakes you can avoid.

Use the correct clip
Any deck 400mm or less from the ground must use the plastic clips. Any deck that has inadequate ventilation must use plastic clips – i.e. a deck 1.5m off the ground with sides enclosed by retaining wall.

Use the clips correctly

Ensure boards are fastened using 1x clip per joist except for butt joins or breaker boards. Use correct installation method for butt joins.

Pre drill oversized holes
Ensure pre drilled holes for trim board screws are drilled oversize at 5mm diameter. Use pan head screws, not counter sunk screws. This allows the trim board to expand and contracts.


This post was written by Elite Outdoor Living in 2015

common decking installation mistakes

Installation advice – please read your manufacturers installation instructions and follow them.


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