How to Lay Decking on Concrete Surface

M. John
Small outdoor garden with a composite flooring

One thing about Ultradecking is that you can lay it on any surface. You can build a composite decking or wood decking on grass and a concrete surface. Homeowners with a concrete surface in their homes already have a sturdy foundation for laying deckings. You have reached the right place if you have a concrete surface and want to lay decking on it. Building decking on concrete is very easy. Let’s see how you can lay decking on a concrete surface?

Laying Deck on Concrete Surface

Installation of composite deck on concrete

You can easily build a deck on a concrete surface. How to lay decking on concrete is the same as constructing conventional decking but with little difference.

Step One – Gather the Materials Needed

If you want to lay decking on concrete, you will need tools to work with, including your decking board. First, you will need either composite or wood decking your decking. Ensure you choose the kind of decking that will last for years. Composite decking is durable and will last for decades. You will also need a measuring tape to know the extent of your decking.

You will also need a hammer, markers, fasteners, screws, and a drilling machine for making holes in the wood. In addition, you will also need to get pressure-treated wood to make your decking frame. Pressure-treated wood has a prolonged lifespan. It will not rot, and termites won’t be able to damage the wood.

Step Two – Level Out the Concrete

Before you start to lay the decking on concrete, evaluate the concrete. Check if there is any spot on the concrete that needs repairing. If you notice rainwater pools, fix the area with cement mix to create a levelled surface. Allow the concrete to dry before you proceed to install the sleepers.

Step Three – Install the Sleeper 

You can now start planning the layout of your sleepers. Use chemical-treated planks as sleepers if you want to lay decking on concrete. And if you don’t want to use wood as your sleepers, you can use metal sleepers. Some homeowners prefer using aluminium sleepers instead of wood since it’s not easily prone to damage. Aluminium is resistant to rot and termite damage, unlike wood. Apart from that, aluminium is also resistant to corrosion.

If you are planning the layout of the sleepers, ensure it runs perpendicular to the wood or composite decking. Arrange the sleepers to face the wall and not run parallel to it. The reason for this is that it will not impede water drainage.

After you have finished installing the sleeper, you can now proceed to install the joists on it.

 Step Four – Install the Joists

The joist will serve as support for your decking. You have to Install the joist on the sleepers. It will keep water from getting to the joist. Also, when installing the joist, ensure that all parts are uniform. If a part of the joist is higher than another part, use a saw to trim it. If it’s shorter, add shims to it to create an equal height.

You can now install your decking joists using screws and clips to hold the joist down to the sleeper. Connect the planks until you have finished constructing the joist. You should also ensure to leave the appropriate spacing when building the joist. The joist should not be too far apart, nor should it be too closed.

Step Five – Lay the Decking on Concrete

Now that you have finished making the decking frame start laying the decking boards. Note that the decking frame comprises both sleepers and joists.  The decking boards are easy to install. Start laying the decking on concrete from the side of a wall or an edge. Use clips and screws to fasten the decking boards.

If you want to lay the composite decking on concrete, do not forget to leave a gap of 15 mm between the walls and the decking. Also, leave a space of 5 mm between the composite decking boards. This will allow the composite decking to expand freely without warping when a temperature change occurs. After laying the decking on concrete, you can now finish the edges to make it more beautiful. You can paint the edges with a matching colour as your composite decking or use picture framing.


It’s easy to lay decking on concrete surfaces. You have to get your materials ready, level out the concrete, and install the decking frame. After that, lay your decking board on concrete.


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