A DIY Guide for a Fresh Start
If your deck has seen better days (think mildew stains, dirt build-up, or that sad gray patina from too many seasons in the sun) it might be time to give it a refresh. Pressure washing is one of the quickest ways to breathe new life into tired wood and prep it for staining or sealing. Best of all, it’s a DIY job you can knock out in a single afternoon!
In this Greenworks blog, we’ll walk you through how to pressure wash your deck the right way—without damaging the wood or your weekend plans.
Safely Pressure Wash A Deck in 5 Steps
Step 1: Choose the Right Pressure Washer
First things first: not all pressure washers are created equal. For wooden decks, 1,500 to 2,500 PSI is the sweet spot. More than that and you risk gouging the wood. Electric pressure washers are great for most decks—lighter, quieter, and less maintenance than gas-powered models.
If you're renting one or pulling it out of the garage, double-check the nozzle. A 25-degree green nozzle is perfect for general cleaning. Want a gentler touch? Go with the 40-degree white nozzle . Get a pack of Pressure Washer Universal Spray Tip Nozzles on Greenworks.com.
Step 2: Clear the Deck
Remove furniture, planters, grills—anything that could get in the way, unless you want to wash them as well! Sweep away leaves, twigs, and loose debris. If your deck boards have gaps, use a putty knife or thin scraper to dislodge anything that’s settled in.
Greenworks Tip: Now is also a good time to check for any loose boards or popped nails that might need fixing before you fire up your pressure or power washer.
Step 3: Pre-Soak and Apply Cleaner
If your deck is extra grimy or has mildew stains, give it a helping hand by pre-soaking it with a deck-cleaning solution. This will make pressure washing more effective. Many pressure washers have a detergent tank, but you can also use a pump sprayer for this important step.
For applying detergent to a deck, remember to use the black nozzle. Known as a “detergent nozzle,” this nozzle is designed for low-pressure applications and is ideal for spreading detergent solution.
Let the cleaner sit for about 10-15 minutes, but don’t let it dry out! Work in the shade or on a cloudy day if you can.
Step 4: Start Pressure Washing (Gently!)
The most important element of this step is to use a soft touch. Begin on the lowest-pressure setting and hold the nozzle about 12–18 inches from the surface. Use long, even strokes and move with the grain of the wood. Don’t hover too long in one spot; wood is softer than you think and can splinter under too much pressure! Work in sections and keep a consistent distance from the deck surface to avoid zebra-striping or uneven cleaning. And if you see a stubborn patch, don't crank up the pressure—simply make another gentle pass.
Step 5: Let Your Deck Dry Completely
Now, we wait! After pressure washing, let your wood decking dry for at least 24 to hours before applying any stain or sealant. (As a reminder, composite decking doesn’t typically require sealing).
Wet or damp wood won’t absorb stain or sealant properly, and rushing this step could undo all your hard work.
Greenworks Tip: Use a moisture meter if you're unsure about your deck’s dryness. Wood should be below 15% moisture content before sealing.
Deck Sparkling? Let’s Keep it That Way!
A Bonus Tip to Keep the Glow Going
Pressure washing once a year is usually enough to maintain your deck’s cleanliness, especially if you follow up with a high-quality stain or sealant. In between washes, a good sweep and occasional rinse will help prevent debris build-up and mildew growth.
Final Thoughts on Pressure Washing a Deck
Pressure washing your deck isn’t just about appearances. It’s about preserving the wood and extending its life. With the right tools and a little know-how, you can transform a weathered surface into something worthy of a backyard BBQ in just a few hours!
Want to see pressure washer magic? Legacy Media makes this old deck railing look new again with the Greenworks 2100 PSI Pressure Washer! Watch it now.
For more information and helpful tips about pressure washing, read our recent blog post on How to Use a Pressure Washer: A Step-By-Step Guide for Beginners.
Written by The Green Team, a creative arm within Greenworks Tools.
Our team of writers, designers and content creators bring a breadth of experience and a touch of fun to all things tools. With an assist from the Greenworks product teams and technology experts, we’re here to provide helpful and engaging content to make your yard (and life!) beautiful.
