How To Clean Composite Decking

February 2022
Anton White

One of the main benefits of composite decking is how durable and easy it is to clean it is. Maintaining a composite decking boards is a simple process to clean and you do not have to do it very often. Whilst the speed of maintenance is great, you must take some time to understand that you can risk damaging your boards if you are to use irregular methods.

This article will explain the easiest and most effective ways to clean your composite decking and outline some of the key things you must NOT do when it comes to decking maintenance to ensure a long lifespan.

Unlike traditional wooden decking, composite decking does not require any staining or painting. The best way to keep your composite decking area looking like new is to just keep the surface clean.

The two main types of composite decking are capped and uncapped, both have slightly different surface properties.

  • Capped Composite Decking has a protective layer that is far more resistant to the elements and everyday liquids or oils, meaning they will not be able to stain as easily as an uncapped decking board (if at all).
  • Uncapped Composite Decking, as the name suggests, has no outer protection layer for extra protection. This means that the surface is slightly more porous and therefore more susceptible to stains.

However, both involve the same simple techniques when cleaning using the below 4 steps.


Step 1 – Remove All Furniture


Removing all furniture or accessories sat on your decking will mean that you will be able to clean your full deck area without having anything in your way. Deciding to leave on your furniture can lead to cleaning problems in the future and cleaning around each piece could take even take longer!


Step 2 – Brush Off All Debris

Using a soft bristle brush, sweep the decking area to remove any large pieces of soil, leaves or anything else that may have ended up on it. It is important to do this regularly, possibly every 3-6 months, as small pieces of dirt can become tough to clean stains if left over long periods of time.  


Step 3 - Water and a Brush

Using warm soapy water and a soft bristle brush, gradually work your way around the area, gently wiping the boards and applying the warm water to keep the surface wet. This step will easily remove all dirt and everyday stains on your composite decking boards. Ensure that you are using a soft bristle brush to get into the difficult areas of the deckboard. We advise that you stick to using a common everyday soap, such fairy liquid as any other strong chemical soaps could stain or even discolour your deckboards.

By this point, your decking area should look something like this:


Step 4 – Decking Cleaner/ Stain Remover

If there are still visible stains, then at this point you may have to look at purchasing a verified Composite Decking cleaning solution. These are very simple to get hold off and are available in most gardening centres. Ensure this is water-based solution, as anything else could be extremely damaging and could end up costing you a lot of money to replace damaged boards. Using the correct cleaner, continue to cover the entire surface and leave to soak for around 5-10 minutes. Use a soft bristle brush to then clean or if the dirt is still showing then use a pressure washer or hose to wash it off.

The reason for using the deck cleaner over the whole area rather than the stained spots, it to give an even colour on all deck boards once you are finished.


What shouldn’t you do when maintaining your composite deck?


  • Do NOT use a wire brush – as this can scratch the surface and leave a very unsightly finish
  • Do NOT use any strong chemicals – these will damage and discolour composite decking. i.e. Bleach
  • Do NOT spray too close with a pressure washer – if using a pressure washer, ensure it is not more powerful than 3100 psi, and make sure that you don’t spray closer than 20cm. Spraying too close and powerful can mark the decking
  • Do NOT use any metal shovels, rakes or sharp objects to clean or remove ice or dirt.


When should I clean my decking area?

Cleaning your decking can be done at any time of the year. However, we recommend that you do so during a mildly warm day. This is so that soap can have the time to dry before you can wash it off and this would be difficult in extreme heat. You may have to then re-wash with clean water to give a spotless finish once dried.

It is worth noting that if the temperature is below freezing, watering down your decking could cause the water to freeze. Meaning cleaning would be almost impossible, and could cause injury to whomever walks on top of it unknowingly! In this instance, simply use a non-corrosive ice melt, designed to not leave residue on the surface of the boards. Lay in preparation for extremely cold weather or where there is ice already in sight. You should clear away any rock salt or sand quickly as to not damage the surface of the boards.

What Now?

Now that you have read all that you need to know about cleaning composite decking, you may begin thinking about using it as an option for your garden or balcony. With so many options available, we know it can seem like a big decision to make. Why not begin by ordering one of our free sample boxes to help you choose which style will best suit you?

You can also call us on 0208 159 2999 or send us an email to to get quotes, guidance and any technical support with your plans. If you think you will require the help of a professional installer, we are happy to recommend one to assist.