dex classic Classic Decking Instructions

dex classic Classic Decking

Overview

Plan the substructure for drainage, ventilation, and expansion space, acclimatise boards before installation, and maintain appropriate gaps to accommodate temperature- and moisture-driven expansion. Follow the recommended cleaning and aftercare steps to help minimise and remove common composite deck stains.

Key Specifications

Quick Setup & Use Steps

1. Acclimatise boards: Place Classic deck boards at the installation site for 72 hours before starting. Do not install below 5°C.
2. Prepare drainage: Ensure sufficient drainage below the deck area.
3. Build subframe: Lay the subframe lengthways with a 1% to 1.5% gradient away from walls, and keep it set off from surrounding walls/obstacles for expansion.
4. Space the subframe: Set the substructure to a maximum of 350 mm centres. Fit fixing clips on every joist/subframe.
5. Fix to concrete with spacing: Fix the substructure with expansion screws to the concrete at 300–400 mm intervals.
6. Plan board joining and edges: Use a double bearer where boards are joined longitudinally. Secure ends of both boards with clips at both sides.

INSTALLING CLASSIC DECKING

Important installation instructions

• Slight colour and surface deviation may occur due to slight differences in raw materials or surface treatment. The deck boards will fade over the first 12 months of being installed. At the end of this period, the surface colour will stabilise.
• The degree of fading will depend on the location of the decking and the resulting exposure to bright sunlight and weather conditions.
• It is advised to place the deck boards in the required installation site for 72 hours before you start the installation for them to acclimatise. The decking should not be installed in temperatures below 5°C.
• We advise using original accessories and components from deX to ensure the warranty remains valid.
• In case of insufficient ventilation, any warranty will be invalidated. There should not be direct contact between the decking structure and the ground (grass, soil, etc.).
• Variations in temperature and moisture uptake will result in expansion.
• A strong and compacted base such as concrete is recommended.
• WPC decking is not suitable for closed and moist environments such as sauna rooms, etc.

PREPARE THE SUBSTRUCTURE

STEP 01 PREPARE THE SUBSTRUCTURE

• Ensure there is sufficient drainage below the deck area.
• Lay the subframe with a slight gradient of 1% to 1.5% away from the walls. It should also be laid lengthways. Keep the subframe set off any surrounding walls or other obstacles to allow for slight expansion.
• Keep the substructure at a maximum of 350 mm centres.
• Fixing clips must be installed on every joist/subframe.
• The substructure should be fixed by expansion screws to the concrete at a distance of 300-400 mm.
• Where the decking needs to be joined longitudinally, we recommend having a double bearer to provide sufficient support for both ends of the deck boards.
• Please ensure that the ends of both boards are secured by clips at both sides.

INSTALLING AND EXPANDING

STEP 02 INSTALLING AND EXPANDING

• The expansion rate of Classic decking can vary depending on different weather conditions.
• Based on this expansion rate, there must always be a gap between two Classic decking boards as follows:
• Allow at least an 8 mm gap on butt joints.
• The distance of at least 15 mm from walls or other obstacles to allow for expansion of the deck boards.
• Important: When fixing the starter clips or intermediate clips, we recommend pre-drilling the subframe with a 2.5mm drill bit to prevent cracking or breaking the subframe, as WPC products have a high density.
• The deck area can be finished with the angle trim product around the perimeter. This provides a neat finish to the deck. Allow the same expansion tolerances as the decking.
• When fitting the matching angle trim, you can use STORMFix, a one-part solvent-free hybrid adhesive with high initial grab and non-slip properties. Angle trims must not be screwed down, as they need to be free to expand and contract.

MAINTENANCE AND AFTERCARE

STEP 03 MAINTENANCE AND AFTERCARE

• Water stain marks can show on composite deck boards. The main types of water stains will generally disappear with exposure to general weathering.
• Water stains from wood tannins will occur inthe early life of your deck as the natural tannins come out of the wood fibres at the surface of the composite decking. This will happen in the early weeks of your deck being laid and will depend on how exposed to the elements your deck is before the weathering process is complete. This type of stain can be more prominent when new decking is exposed to direct sunlight in the first few months of its life.
• Water stains from water pooling or dripping can leave a “shoreline” effect. The visibility of the stain depends on variables like how dirty the decking is and how quickly the water dries from the water pooling. Again, this can be exaggerated in hotter weather.
• Both types of marks/stains will disappear over time unless you have a recurring problem that continually allows water to land on the composite decking, e.g., a drip from the gutter will continue to make marks.
• Oil or cigarette stains, etc., can be very difficult to remove from the surface, so avoid
• We advise letting the composite decking weather naturally over time. However, we understand you want to be proud of your new deck once installed, and if you feel the need to try and remove the marks yourself, washing with clean, hot water should wash away most stains.
• Don’t wash your decking while it’s still hot from a day’s sunshine.
  1. Pour clean hot water on the deck and let it sit for 5-10 minutes.
  2. Work with a soft-bristle brush.
  3. Pressure wash (at low pressure and wide fan) or rinse down with hot water (preferred option).
  4. Push the water off the deck with a squeegee brush.
  5. Mop up any wet areas with a clean sponge mop.
• Watermarks may require more hot water or repeated procedure if they are long-standing.
• Important: Never use strong detergent or bleach-based products.

Warranty

• Please note: The warranty does not cover variation or changes in the colour of the Classic decking. Contact our sales team for full warranty details.

CUSTOMER SERVICE

• info@dexoutdoorliving.co.uk
• 01278455326
• dexoutdoorliving.co.uk

• Colour/surface changes or fading: Slight colour/surface variation can occur from raw material differences. Deck boards will fade over the first 12 months; the surface colour stabilises after this period. Fading depends on sunlight and weather exposure.
• Water stain marks: Some water stains disappear with general weathering. Types include (a) tannin stains in the early weeks (more prominent with direct sunlight early on), and (b) “shoreline” effects from pooling/dripping where visibility depends on dirt level and how quickly water dries. If water continues to land (e.g., an ongoing drip), marks will continue—fix the source. Avoid oil or cigarette stains where possible.
• Stains that persist: Use the manual’s cleaning method with clean hot water (soak 5–10 minutes), a soft-bristle brush, then a low-pressure pressure wash or hot-water rinse. Watermarks may need more hot water or repeated procedures if they are long-standing.
• Cracking during clip installation: Pre-drill the subframe with a 2.5 mm drill bit when fixing starter/intermediate clips to help prevent cracking/breaking, as WPC products have a high density.
• Warranty invalidation concerns: Ensure there is sufficient ventilation and no direct contact between the decking structure and the ground (grass/soil). Also ensure the decking is suitable for the environment; WPC decking is not suitable for closed and moist spaces such as sauna rooms.