5 Essential Things You Will Need to Clean a Composite Deck

Updated on: 05/04/2022

A composite deck is a beautiful addition to any outdoor living space and is made up of a good mix of

both wood and plastic. And although a composite deck is a wonderful choice for your front or backyard, it does require a bit of upkeep. You’ll need to provide your deck with the proper maintenance in order to keep it looking new for years to come.

To clean a composite deck, stores offer homeowners and building owners cleaning solutions. However, many of these cleaning solutions contain harsh chemicals, which aren’t healthy for yourself, small children, nearby plants, and even the deck itself. Over time, if you continue to use harsh cleaning chemicals on your deck, the chemicals will begin to break down your deck as well as the grim on top of it.

So, what’s the best way to clean a composite deck? Keep reading for our diy deck cleaner tips, recipes, and more that you’ll need to keep your deck looking its best!

DIY Deck Cleaning Recipes

There are a lot of homemade deck cleaning recipes out there that are either great, okay, or possibly toxic if you mix the wrong chemicals together. We’ve put together some tried and true diy deck cleaners that’ll help you keep your deck looking great in between visits with a professional exterior washing company.

➡️Pro Tip: Take the time before you get started to completely clean off the deck. Kids toys (or dad’s) can quickly become an irritation when you have to stop scrubbing just to find a place to put them.

Grab Your Supplies

Before you start blending your homemade deck cleaner, first you need to gather the supplies you’ll need to clean your deck.

Item Why
Floor Scrubber With all of these cleaners, you’ll need to at least lightly scrub the surface. For that, you need a good floor scrubber.
Bucket Aside from having a container to mix your DIY cleaner in, you’ll need it for holding the mixture and moving it around with you on the deck.
Measuring Cups Purchase measuring cups especially for cleaning tasks like this!
Hand Scrubber While hopefully unnecessary, it’s always a good idea to have a comfortable, ergonomic hand scrubber for tough spots.
Gloves Avoid skin irritation or injury with a pair of thicker gloves. Dishwashing gloves are typically fine.
Face Mask For those who have allergies or deal with a weakened respiratory system, it’s a good idea to invest in a good face mask.

1. Soapy Deck Scrub

Dish soap might not be as powerful as some cleaners out there, but it gets the job done pretty well. Plus, this homemade soapy dish scrub contains bleach that gives it the extra kick it needs to eliminate all bacteria and fungi on your deck.

To make this soapy deck scrub you’ll need:

  • Household Bleach, 2 quarts
  • Dish Soap (ammonia-free), ¼ cup
  • Warm Water, 2 gallons


Mix all of the ingredients together and use them immediately. Be sure to rinse off the deck completely when done.

A note about bleach and ammonia!

When bleach and ammonia are mixed, it produces chloramine gasses, which can lead to problems breathing. For those who may have a compromised respiratory system or are dealing with symptoms of long COVID, this could be a very dangerous situation. It’s important to make sure your dish soap is ammonia-free!

If you have a deck that is quick to build up dirt, grime, and grease on it, then this is one of the best cleaning solutions for it. Just be sure to protect your plants near the deck with a plastic tarp before cleaning your deck.

➡️Pro Tip: For a gentler solution, you can mix together 1 gallon of water with 1 gallon of white vinegar. Although it works, it might not be as effective as bleach.

2. Homemade Mildew and Algae Deck Cleaner

If your deck has mildew and algae growing on it, then the first thing you need is a composite deck cleaner.

To make this effective deck cleaning solution you’ll need:

  • Household Bleach, 1 cup
  • Trisodium Phosphate (TSP), 1 cup
  • Warm Water, 2 gallons


Wash your deck down prior to applying the solution. Then, mix all of the ingredients together and apply it to your deck. Use a brush or broom to scrub the solution into the wood.

Give it about 10 to 15 minutes to soak into the wood and penetrate the layer where mildew and algae are present. When finished, simply rinse the solution off with water!

3. Powdered Bleach Scrub

A powdered bleach solution helps remove mildew and algae all while preventing wasps and yellow jackets from building nests on your deck. It’s not as harsh as liquid bleach, and once the solution is made, you’ll need to use it right away. It’s a perfect solution for decks that don’t suffer from stains and decks, but need a good washing in between yearly deep cleanings.

To make this powdered bleach scrub you’ll need:

  • Liquid Dish Soap, ¼ cup
  • Hot water, 2 gallons
  • Powered Laundry Detergent, 2 cups


Mix all ingredients together. With this solution, you may have to do multiple applications or really put some muscle behind your scrubbing to work it into the material of your deck.

Try to Maintain A Dry Surface at All Times

Although your composite deck was made to withstand water, it’s important to keep a dry surface at all times as much as possible. Mildew and algae both need moisture to grow, so keeping your deck dry is going to be your best bet in preventing them from growing.

➡️Pro Tip: Ensure that your deck has at least 6 inches of room underneath it and dryer vents point away from the deck. This is going to help the deck “breathe.”

A dryer vent near your deck will direct hot air towards it, which is another element loved by mildew and algae. And don’t forget to be on the lookout for standing water on your deck after it rains. You’ll need to remove this water and then determine what the cause is and possibly fix it.

Hire a Team of Surface Cleaning Pressure Washers

Ultimately, a solid team of professional surface cleaning pressure washers is what’s going to keep that deck of yours looking top-notch for years and years to come. Keep these solutions nearby for daily, weekly, or monthly cleaning, but when it’s time to get a deep cleaning completed, you’ll need a good pressure washer.

Pressure washing is a great way to naturally clean your composite deck without using harsh chemicals or causing damage to your deck.

After reading this guide, we hope you now know how to clean a composite deck the right way! Use these homemade cleaning solutions to clean your deck at home regularly. But when it’s time to give your deck a good deep cleaning, you’ll need to call in the professionals.

Schedule an appointment online today and let us help you get your composite deck back to its original beautiful state!

Related Reading

Frequently Asked Questions about homemade deck cleaners

What’s good and what isn’t when it comes to your DIY deck cleaning options? Browse our answers here, or ask your own questions!

What household items can you use to clean the decking?

You can use typical household cleaners, like dish soap and a scrub brush, to clean your deck. In our article above, we go over how to make your own homemade deck cleaners as well as the supplies you’ll need!

Can I make my own deck cleaner?

Yes, you can. While we recommend leaving it to the professionals, it’s easy to blend your own DIY deck cleaner and use common tools to clean your composite deck.

Can I use Dawn to clean my deck?

Yes! You can use any ammonia-free dish soap to clean your deck. Dawn is a good choice because it’s gentle, yet very effective and a much safer option for local wildlife.

What kills mold better: bleach or vinegar?

Both are very effective but in their own way. While bleach kills mold spores on the surface, vinegar can work deeper, removing mold from porous surfaces, such as your wood deck.

Will bleach damage a wood deck?

In excess, yes, it can. We don’t recommend using a lot of bleach in our DIY cleaning recipes because excessive use can discolor your deck. But, in small amounts and infrequent uses, it should be fine.

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