What is the Best Way to Clean a Deck?

The best way to keep your deck looking great for a long time is to regularly clean it. A dirty deck can become unsightly and even dangerous, as moss and mildew may grow.

Start by sweeping the deck with an outdoor broom to remove any dirt, debris or pine needles that have collected. Next, if your deck is composite, use a bucket of warm soapy water and scrub the surface with a brush.


As your deck is exposed to the elements, dirt builds up and mildew and mold spores can thrive. Sweeping regularly will keep your wood deck looking fresh and new. If stains are present, consider using an oxygen bleach cleaner (such as Oxiclean or Oxy-Boost) in warm water to remove stubborn debris and discoloration. Oxygen bleach products typically contain sodium percarbonate and/or sodium perborate and can also be found in common laundry detergents.

To use, saturate the deck surface with the cleaner and wait for it to soak in (there is usually a time frame indicated on the label). A garden hose should be used to mist the deck periodically to help keep the deck wet.

If the deck has visible mildew, add a cup of powdered Borax to the cleaning solution. This will help to banish any mildew spores and won’t harm nearby landscaping plants as chlorine bleach can. Scrub the deck with a long-handled brush and rinse thoroughly with a garden hose.


Depending on how dirtied your deck is and what types of staining you’re facing, a simple detergent may do the trick. Pouring four litres of warm water into a bucket and mixing in 250ml of laundry detergent is a cheap, effective option that should work on mildew stains, but don’t let the solution sit on your deck for more than fifteen minutes or it may discolour the wood.

For a deeper clean, consider using oxygen bleach, which is non-toxic and breaks down into sodium bicarbonate and oxygen when it comes in contact with water. After mixing the solution, apply it with a long-handled brush or broom and scrub in the direction of the grain.

Don’t forget to clear your deck of furniture, grills, rugs and other items, as keeping them on the surface can scar or gouge the wood and expose them to cleaning products. Also cover any grass or plants to protect them from any cleaning solution spillage.

Apply a Stain

Before applying a stain to your deck, you should use a garden house or gentle power washer to wash away any remaining debris and dirt. Make sure to cover any plants, grass or yard ornaments near the deck so they don’t get splashed with cleaning products.

If your deck has a lot of mold or mildew, you can try cleaning it with diluted white vinegar. However, it’s best to purchase a cleaning solution designed for the type of deck you have. Vinegar may kill mildew, but it can also leach the color out of your deck.

Once the deck is completely dry, if it appears highly worn or weathered, you can lightly sand the wood to revive it and raise the grain for easier stain absorption. Before you apply a stain, you should do a test to see how it looks. A good quality exterior stain combines pigment with a water and weather proof sealer that can protect the deck from the elements.


Getting your deck in top shape is a great way to extend its life and keep you, family members, and pets safe. A dirty, discolored deck not only looks bad but can lead to structural damage, mildew, and the growth of moss (which is a safety hazard in itself).

Start by removing any plants or furniture, and power washing it with a pressure washer at mid-level pressure. Use the detergent or cleaning solution recommended for your deck material and apply it with a long-handled scrub brush, paying special attention to crevices.

You can also make your own cleaning solution, combining a bucket of warm water with the appropriate amount of white vinegar or other home-based cleaner. Rinse thoroughly with lots of fresh water to remove all traces of the cleaner. Next, apply a wood brightener. This helps the wood look like new and opens its pores so it can better absorb protection. You can find wood brighteners at any hardware or general store.