Outdoor sitting space with firepit featuring engineered decking from TimberTech

Composite decks are popular for their low-maintenance beauty and long lifespan – but they still need attention every once in a while to keep them looking their best. We recommend cleaning your deck at least twice a year—once in the spring to start the season, and once in the fall to remove pollen and dirt before winter.

Unlike wood decks, composite decking resists mold, mildew, and insect infestations. Keeping your composite deck clean has more to do with removing surface blemishes and preventing discoloration and scratching. Read on for a simple step-by-step cleaning guide – including what products you’ll need for this straightforward DIY project.

Cleaning Composite Decking in 5 Simple Steps

Light wood-colored composite deck surrounded by fall foliage

Your cleaning project will need to be tailored to the condition of your particular composite deck, and should abide by any manufacturer recommendations. Not all composite decking materials are the same, and you’ll want to be sure your cleaning products don’t cause any damage – both for the sake of the deck’s appearance and the validity of your warranty. But rest assured, cleaning a composite deck is ultimately a simple process that follows a straightforward series of steps.

1. Remove furniture and objects from the deck surface

The first step when cleaning your deck is to remove all objects from the surface. During this step, take note of where your outdoor furniture or other items are placed. You’ll want to rotate where you place them after your deck cleaning project is done. Leaving objects in the same spot for long periods of time can lead to uneven fading.

2. Clear the deck of dirt and debris

Next, clean off any loose dirt, leaves, sticks, and other debris from the surface of the deck and between the deck boards. While these things aren’t inherently harmful to composite decking boards, they can be a breeding ground for mold if they get wet. Depending on the season and where your deck is situated, you may only need an outdoor broom for this step. If there’s a significant amount of loose debris on your deck, use a leaf blower to prepare the surface.

Removing snow or ice?

Use a plastic shovel and calcium chloride ice melt. Metal shovels and harsh ice melts easily damage composite decks.

3. Prepare the proper cleaning solution

Depending on the level of mold or dirt you’re tackling, you may be able to successfully clean the deck surface with a simple, homemade solution. Diluting a mild soap (like Dawn dish soap) in warm water makes a great deck cleaner for mild blemishes.

If you need a stronger cleaning product for stubborn stains, check the manufacturer-recommended solution for your composite deck. Not all composite decking cleaners are interchangeable, and you’ll want to be careful the chemicals in a given product do not damage your deck.

A note of caution: No matter what, stay away from chlorine bleach! This harsh chemical is guaranteed to cause damage to any composite deck.

4. Clean the deck one section at a time

Once it’s time to apply the solution and start cleaning, work in one small section of your deck at a time. Cleaning a large surface area at once will result in the cleaning solution drying before you get a chance to scrub it and rinse it off. If the cleaning solution dries on the deck boards, it can be difficult to remove (drying time also depends on whether you are working in direct sunlight). Instead, work on a smaller section, scrub the solution onto the deck boards, and then thoroughly rinse it off before moving on.

Don’t forget to check the manufacturer’s recommendations for cleaning materials to find the best type of deck brush. Some deck brands recommend using a soft bristle brush to clean composite decking – premier decking manufacturer TimberTech calls for a medium or stiff, natural fiber scrub brush for their composite decks.

5. Rinse off any remaining soap and dirt

When the whole deck has been cleaned, you’ll need to rinse off any remaining soap and grime. If your garden hose won’t cut it, you can use a pressure washer with a fan tip – as long as you follow a few guidelines. Do not exceed 1,500 PSI when you pressure wash your deck, and maintain at least 6 inches of distance to avoid damaging the deck surface. Spray with the grain of the deck boards, and avoid using brighteners and solvents with the pressure washer.


How to Clean Deck Railings

To clean your deck railings, scrub the surface with a soft cloth or sponge dipped in warm soapy water, and rinse with water when finished.

Stains and heavy soiling might require more potent cleaning solutions. Be sure to check the manufacturer-recommended cleaning products for the railing material on your deck to make sure the chemicals you use won’t cause any issues.

Composite Decking Care Tips

Composite decking doesn’t require nearly as much maintenance as a traditional wooden deck. But there are still a few best practices to follow when using and cleaning your composite deck. As always, make sure you know the specific care instructions for your deck provided by the manufacturer. Here are a few tips to keep in mind:

  • To avoid discoloration, don’t leave rubber-backed mats, tarps, or pool toys on your deck for an extended time.
  • Periodically rotate objects and furniture on your deck to prevent uneven fading and dirt build-up.
  • Regularly sweep your deck to keep it clear of dirt and debris that can cause mold.
  • When removing snow or ice, only use a plastic shovel (the sharp edge of a metal shovel will damage the deck) and a calcium chloride ice melt safe for composite decks.
  • Always check manufacturer recommendations and care instructions before using a cleaning solution or other type of cleaning product on your composite deck.

Plan to clean your composite deck thoroughly at least twice a year, but sweep away debris regularly to keep mold and mildew from accumulating on the surface. It’s also a good idea to clean your deck if it’s been exposed to extreme weather or covered by standing material—such as water, dirt, snow, or ice—for an extended period of time. This will help protect its color and prevent damage.

Recommended Cleaning Products for TimberTech Composite Decks

Dark Roast decking from the TimberTech Composite Reserve CollectionDark Roast decking from the TimberTech Composite Reserve Collection

TimberTech’s premier composite and PVC decks create stunning outdoor spaces that last for decades with minimal care. For best results when cleaning your TimberTech deck, homeowners should use TimberTech’s recommended products.

Timbertech DeckCleaner is specially formulated to remove blemishes without harming the composite or PVC materials used in TimberTech’s decks.* Homeowners should not use composite deck cleaners such as Corte Clean®, Thompson’s® Water Seal®-Oxy Action, Olympic® Deck Cleaner, or other brands of composite deck cleaners with TimberTech products, since the capping material is not a wood and plastic composite.

*Note that Timbertech® DeckCleaner™ is for exclusive use on TimberTech AZEK, PRO, and EDGE decking, porch, and railing products, and should not be used on TimberTech ReliaBoard, DockSider, or uncapped composite decking.

TimberTech also recommends that homeowners use a medium or stiff, natural fiber scrub brush for their composite decking. Read the full TimberTech decking cleaning and care instructions for more details.


TimberTech DeckCleaner

To clean your deck railings, scrub the surface with a soft cloth or sponge dipped in warm soapy water, and rinse with water when finished.

This non-toxic, bleach-free formula can be applied to your entire TimberTech deck or be used to spot treat stains. When properly diluted, a single 1-gallon bottle yields 4 gallons of cleaner to clean approximately 1,000 square feet of surface area.

Get Expert Advice on Your Composite Decking Project

The wonderful thing about this cleaning project is that a little goes a long way. With just a simple, thorough cleaning a couple of times a year and minimal ongoing upkeep, your composite deck will be a beautiful place for relaxation, entertainment, and community for years to come. If you’re concerned about the cleaning products you have or the condition of your deck, don’t hesitate to consult with the home improvement experts at Ring’s End. Contact us by using our online chat or by texting (203)-PRO HELP. We’ll be happy to help!