Tools and Materials
Get Ready to Pressure Wash a Deck or Fence
Before you begin washing the deck, get the work area ready.
- Remove any obstacles to prevent tripping and tangling hoses.
- Cover nearby plants, electrical components and light fixtures.
- Sweep away loose debris.
- Close nearby windows and doors.
- Keep your pressure washer in a safe area while you clean.
- Pay attention to the wind direction.
- Check your owner’s manual to determine the proper spray pattern and spray tip. Generally, you need a wide-fan tip for pressure washing a deck or fence to avoid damage to the wood.
- Put on eye protection, hearing protection and work boots.
- You’ll use a different spray tip for applying cleaning chemicals than you will for actually pressure washing the decking, railing and frame.
Power Washing Decks vs. Pressure Washing Decks
You might be wondering if there’s a difference between pressure washing and power washing a deck or fence. Pressure washing refers to using a machine that washes the deck with high-pressure cold water. Power washing a deck technically refers to using high-pressure heated water, which can clean better than cold water. True power washers are commercial grade machines, but you’ll often hear homeowners use the terms pressure washing and power washing interchangeably.
Don’t run a gasoline-powered pressure washer indoors or in an area that doesn’t have proper ventilation. Keep the engine exhaust away from occupied areas.
Wash a Deck or Fence With a Pressure Washer and Detergent
You can find pressure washer chemicals or detergents specifically for washing a deck or fence. Follow the manufacturer’s instructions on the type of pressure washer chemicals or detergent to use.
Test the Pressure Washer Spray
Your manual might also specify the type of spray tip or nozzle and distance it should be from the surface you’re cleaning. Typically, you need to keep the nozzle at least 6 inches from the boards. Before you begin pressure washing a decking or fence panels, test the spray pattern and distance on a hidden area of the surface to make sure the spray doesn’t damage the wood.
Apply the Detergent
Before you begin to pressure wash the deck or fence panels, apply the detergent with a low-pressure nozzle suitable for soap.
- On vertical surfaces, apply the detergent from the bottom to the top.
- Apply the cleaning solution to cover the width of a few boards with each pass.
- Use a stiff-bristle brush to scrub in tight corners and between deck balusters.
- Consider using a rotating scrub brush attachment for dirty or stained spots.
- Don’t work on surfaces that are hot or in direct sunlight.
- Allow the detergent to remain on the surface you’re cleaning for the time specified by the manufacturer, but don’t let it dry.
- Once you’ve finished applying the cleaner, follow the pressure washer manufacturer’s instructions to flush the cleaner from the machine.
Wash the Deck or Fence
- Attach the wide-pattern cleaning nozzle. Turn it to create a vertical spray pattern if you’re pressure washing decking or a horizontal pattern if you’re cleaning fence boards.
- On vertical surfaces start at the top and work downward to prevent streaks. Use overlapping passes for more even cleaning and keep the nozzle a consistent distance from the wood.
- Work along the grain of the wood to spray the detergent off of the deck or fence.
- Keep the nozzle at about a 30-degree angle to the boards.
- Follow the manufacturer’s instructions for relieving water pressure, removing liquid from the pump and storing your equipment properly.
Don’t operate the pressure washer without the water supply connected and turned on. Your manual may specify letting the pressure washer cool down periodically.
Staining After Pressure Washing a Deck or Fence
If you’re applying a new stain and sealer, let the deck or fence dry for 48 hours. Next, you’ll need to remove the existing finish by sanding the deck or using a wood stripper. If you sand the deck, wear eye protection and a respirator. If you use a wood stripper, follow the instructions for applying neutralizing the stripper product. Wear the specified safety gear.
Safety Tips for Pressure Washing a Deck or Fence
Read and follow all of the manufacturer’s safety instructions for your pressure washer. General guidelines include:
- Know how to quickly turn off the pressure washer and release pressure from the system.
- Operate a pressure washer only when you’re on a stable surface where you have good balance and solid footing.
- Never leave a spray gun or wand unattended while the pressure washer is running.
- Always be aware of where you’re directing the pressure washer spray.
- When using a pressure washer wear work boots, hearing protection and eye protection as specified by the manufacturer.
- Never point a pressure washer spray gun or wand at people, animals or plants.
- When using cleaning chemicals, always follow the manufacturer’s instructions.
FAQ for Pressure or Power Washing a Deck
Here are some answers to common questions about to pressure washing a deck.
Can You Pressure Wash Composite Decking?
Composite decking manufacturers generally don’t recommend using a pressure washer to wash a composite deck. Using a pressure washer on composite decking may void the decking warranty. Because composite decking is softer than wood, it can be easy to damage the deck. Once damaged, it becomes susceptible to staining and sun damage. Follow the decking manufacturer’s recommendations.
Will Pressure Washing Remove Deck Stain?
While a pressure washer will remove dirt, mold and mildew stains from a deck, pressure washing isn’t a good way to remove existing wood stain and sealer from a deck. The pressure necessary to remove the finish could gouge or damage the wood. Use a wood stripper product according to the manufacturer’s instructions to remove an existing stain and sealer. You can also sand away the existing finish. Just be sure to wear eye protection and a respirator.
Should You Pressure Wash Your Deck Before Staining?
Yes, you should pressure wash your deck prior to staining. After washing the deck and letting it dry, you’ll likely need to apply a wood stripper to remove the existing stain and then neutralize the stripper according to the product instructions. Sanding the deck can also remove existing wood stains and sealers. Be sure to wear eye protection and a respirator.
How Often Should You Pressure Wash a Deck?
Pressure wash your deck at least once a year. This will help prevent mold from developing and will keep your stain looking clean and bright.