how to clean a composite deck, How to Clean a Composite Deck

How to Clean a Composite Deck

Composite decks are much easier to clean than many other decking options. Solid wood decks require extensive maintenance and care, while composite materials only need a fraction of the attention.

However, the reduced need for maintenance doesn’t mean you can leave these decks unattended. Let’s go over everything you need to know about how to clean a composite deck.

Why Are Composite Decks Easier to Clean?

Composite decks were made to provide homeowners with a low-maintenance option when compared with traditional lumber decks. They’re made with a combination of vinyl/plastic and wood, coated with a vinyl treatment.

The amount of wood varies depending on the type of composite decking, with many products having anywhere between 40-70% wood. Antifungal chemicals and preservatives help to treat and protect the wood materials from rot.

The combination of wood and vinyl make composite decks more durable and easier to clean than decks made from wood alone. They still need some maintenance to stay looking beautiful and inviting, but fortunately, you can clean them just using tools you have around the house.

Bonus: Click here to read our round-up of the best composite decking brands of 2020.

Cleaning Tools

Luckily, cleaning a composite deck doesn’t require any specialized tools. Odds are that you already own all the items you need to clean your composite deck properly.

You’ll need to gather from around the house these tools:

  • Broom
  • Bucket of warm water
  • Bucket of soapy water (you can buy special composite deck cleaner or just use dish soap)
  • Deck brush (make sure the bristles are on the softer side)
  • Hose

The Composite Deck Cleaning Process

There are six basic steps to cleaning a composite deck.

  1. Clear your entire deck of any furniture or objects that would get in the way of the cleaning process.
  2. Use the broom to sweep the entire area and remove any leaves, debris and excess dirt.
  3. Spread warm water over the deck to get it ready for soap. Don’t worry about wetting every single inch; just spread it out the best you can.
  4. Mix soap and warm water, similar to the ratio you might use to wash your dishes.
  5. Dip the deck brush into the bucket of soapy water and start scrubbing your deck. Don’t be afraid to apply significant pressure to clear away as much dirt as possible—composite is hardy and can take it.
  6. Once you’ve scrubbed the deck, take a hose and rinse away all the soapy water. The sun will take care of the drying part.

What NOT to Do

Composite is popular because it’s incredibly easy to maintain and can withstand a lot. That being said, there are few considerations to keep in mind to keep your deck looking its best.

You should generally avoid industrial chemical cleaner because harsh substances can eat away at the composite material. Bleach is also not advisable because it can discolor the deck and ruin its appearance.

If you are unsure if a particular cleaning solution will work for your deck, you should check out the manufacturer’s recommendations. You can generally find guidelines for care on the manufacturer’s website or in the materials that came with your purchase.

Finally, it may sound obvious but it needs to be said: don’t clean your deck in the rain or snow. Wait for a bright and sunny day.

How to Clean Common Problem Substances

Decks that get a lot of traffic and exposure to the elements will typically get dirty easily. Let’s discuss some tactics for dealing with the most common sources of grime.

Mold and Mildew

Mold and mildew are not common issues for composite deck owners. Although vinyl caps help with protection, some decks still have organic wood materials at their core and are susceptible to rot. 

You can prevent mold with the soap and water cleaning routine described above. Also, keep an eye out for cracked, torn, or broken deck boards throughout the year, as moisture can seep through and cause problems. Get these repaired right away. If you have a wooden deck, check out this guide on removing green algae from a wood deck.

Beverage and Food Stains

You can prevent food and beverage stains with a simple dry paper towel. The plastic in the composite prevents liquids from soaking in immediately. If this technique doesn’t do the trick, the soap and water method can finish the job.

If you’re struggling with stains despite thorough cleaning, check your composite manufacturer’s warranty to learn about getting a replacement. Many warranties cover stains from food and drinks.

Grease and Oil

Grease and oil should be blotted up as soon as possible. The longer these stains sit, the more likely they will sink in and become permanent.

Once you’ve soaked it up, use the water and soap method to clean up any residual grease or oil. A grease-cutting dish soap will work wonders.


Unfortunately, pollen tends to be a bit more stubborn to eliminate. Often, soap and water alone will not do the trick.

You may need to resort to power washing to remove pollen thoroughly. You may also consider moving pollen-producing flowers away from the deck, as well as trim the branches of trees that may drop pollen on the boards.

Keep reading below to learn our tips for power washing your composite deck.

How to Deal with Ice and Snow

You can shovel your composite deck like you would your sidewalk. However, you must also be careful when engaging in this activity.

Using a plastic shovel will be your best bet because metal shovels with a cutting edge can easily scratch composite decks. If you want to be especially careful following light snowfalls, you could use a broom or leaf blower to remove thin layers of snow.

If you are dealing with particularly stubborn ice, you may opt to use rock salt or calcium chloride to melt it before attempting to shovel. Rock salt is safe for use on modern composite decks, but make sure to wash or wipe it away as soon as it’s done its job.

How Often Do Composite Decks Need Cleaning?

There’s not a hard and fast rule as to how often composite decks need cleaning. It’s more important to clean as needed to prevent stains from setting.

In general, try to clean your composite deck twice a year to take care of dirt and debris buildup. Many homeowners give their deck a good scrub once it’s warm enough to spend time outside and at the end of the outdoor season.

Can You Pressure Wash?

In general, yes. However, you need to be careful not to damage when power or pressure washing.

Here are a few things to keep in mind if you want to go the pressure washing route:

  • Always use a fan tip on your pressure washer. This will ensure that the water diffuses enough not to damage the deck.
  • Keep the pressure below 1,500 PSI so you don’t risk denting the boards.
  • Don’t place the nozzle of the pressure washer too close to the surface of the deck. Always try to keep at least six inches of separation to avoid damaging the outer vinyl layer.
  • Follow the grain of the deck boards as you wash. Going against the grain leads to a greater chance of dents or damage.

Still Need Help? Contact Us!

If you have any additional questions about cleaning your composite deck, reach out to the experienced team at Decks & Docks. Contact us today and a deck pro can help with any concerns you have.