Decking Over Concrete

"I wish we had installed decking instead of concrete!" If a thought like this has ever crossed your mind, take heart. You can install decking over concrete. In fact, installing decking over concrete can be less expensive than installing decking alone or repairing a badly damaged concrete slab.


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Installing Decking Over Concrete

Installing decking over concrete will raise the level of the floor up to 75mm, so make sure you can do this before you go out and buy decking supplies. The condition of the concrete may also have an effect on the completed project. If the concrete surface shows evidence of subsidence, it may not make a stable surface for laying the decking. Usually this will only be the case in very old, damaged concrete, though.

Once you've decided that you can install decking over concrete, you can take the following steps to prepare the ground for installing the decking material:

• If there are low spots in the concrete where pools of water form, use a self-levelling compound to level the concrete.
• You will need to install treated battens to fix the decking to. It is important that the battens are level and flat. You may have to use shims to accomplish this.
• It's best to lay PVC spacers under the battens so they don't act like dams and cause water to collect under the deck.
• The battens need to be fixed to the concrete using a hammer drill with a concrete tip and concrete screws.

Preparing the surface and laying the sleepers is the hardest part of the job. After that, simply install your decking as you would on any other deck.

While there are only a few steps to preparing the surface for the decking, it's important that each of the steps is carried out properly. After you have installed the decking material, you won't be able to access the concrete underneath. If water is allowed to pool under the decking, it can cause problems later on. The sleepers are the "foundation" for your decking, too. If they are not flat or level, your completed deck will not be flat or level, either. Consider getting quotes from decking contractors if you are inexperienced or want to install a larger deck over concrete.