How To Pressure Wash A Wooden Deck Without Damaging It

Whether bonding with family over a cup of tea, entertaining guests with fancy alfresco dining, or simply kicking back in a hammock chair with your favorite book to soak some Vitamin D, backyard decks are the perfect spot to make the most out of the lovely summer evenings. But once a season (or two) ends, the once-cozy backyard starts showcasing signs of exhaustion โ€” the pile of leaves in the corners, the colorful punch spill left by your toddler, the tannin spots around the planters, the mildew that has started growing, and whatnot!

So why not deep-clean your deck before summer begins? This blog post will guide you as to how you can revamp and maintain your wooden deck with a pressure wash while preventing any damage โ€” read on to learn more!

Comprehensive Guide With Detailed Steps

Below weโ€™ve broken up the entire pressure wash process into 6 simple steps to make things easier and more simplified.

Select The Right Pressure Washer

A pressure washer is a smart machine that can clean any and every hard stain from your deck, given that it is chosen and used professionally.

Pick a washer with a pressure of around 1200 to 2400 psi or one with a lower pressure of 500 to 600 psi for a deck made of gentler wood, such as pine or cedar. Quick Tip: Look for an option that allows the intake of cleaners (like a wood brightener and deck stripper), as it will help you spray them easily through the wand.

Pre-treat The Surface

Before initiating the wash process, prepare the deck by fixing broken balusters and split boards. Once done, apply a mixture of non-toxic bleach (or mild dish detergent) and water with a deck brush.

Donโ€™t forget to cover your plants and any grass nearby with plastic to protect them from potential damage.

Brushing a deck

Practice Using The Equipment

Do a trial test with the washer in an inconspicuous area, such as boards that are out of sight or a stair tread (since it is easier to replace if etching occurs). Begin with low pressure and increase incrementally till you find the appropriate setting to wash a wood deck effectively.

Power Wash The Deck

Hold the wand tip about 12 to 16 inches from the deck's surface and engage the trigger while ensuring you donโ€™t go closer than 6 inches. Start moving in a sweeping surface with your arm moving laterally back and forth.

Quick Tip: To keep a consistent distance between the deck surface and the spray tip, avoid pivoting your arm.

High pressure cleaning a deck

Polish & Brighten The Wood

For wood that is darkened or stained with mildew, apply an oxalic-based wood brightener according to the manufacturerโ€™s recommendations on the label. It works fast, doesnโ€™t harm the wood, and is eco-friendly. Rinse the deck again.

Quick Tip: This step will roughen the wood fibers, so the deck will need to be sanded before it can be re-stained.

Apply The Finish

Let the deck dry out before proceeding with the finishing stain. You can also use a dry broom to push off excess water. If required, sand the deck before applying the stain with 60- to 80-grit sandpaper.

Next, apply the finish with a foam applicator pad first on the top rail and then on the posts. Use the applicator pad to clean any stain that drips on the deck to prevent spotting.

Quick Tip: You have two options for the stain: water-based and oil-based. Oil stains easily penetrate the wood grain and require less work during application. They last 2-4 years. Water stains require more work before application, but they last up to 4-6 years.

Staining a deck

Safety Precautions To Be Considered

  • Safety goggles for protection from debris that might flick up.
  • Ear defenders for protection from the loud water pressure.
  • Rubber gloves for protection from cold water and cleaning detergent.

Tips & Tricks For An Effective Cleaning

  • Avoid changing the water pressure settings during the process to prevent cleaning marks.
  • Move the nozzle in the same direction as the woodโ€™s grain for a more natural end look.
  • Execute overlapping lines to conceal watermarks while washing.
  • Do not pause in one place.
  • Combine the sweeping, feathering, and long sweep methods for more effective results.
  • Know what your wood needs to pressure wash a wood deck efficiently. Natural wood, for example, needs to be cleaned and refinished annually, pressure-treated wood needs to be cleaned and refinished every two to three years, while composite material only requires cleaning (not refinishing) after every 2 to 3 years.


While washing a wood deck might seem tiring and overwhelming, a pressure wash is a super-effective way to breathe new life and a fresh appearance into your backyard. Just make sure to choose the right equipment and follow the aforementioned steps and advice for a safe and fruitful cleaning process that will last you a good time!

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