Pressure Washing
What PSI to Pressure Wash a Wood Fence (500 to 1,200 PSI)
Quick answer
A wood fence takes 500 to 1,200 PSI and about 1.2 GPM with a 40 degree tip held 12 to 18 inches away, worked with the grain from top to bottom. A 100 foot run of 6 foot fence is about 1,200 square feet of board and takes roughly 333 minutes at 1.2 GPM.
Fences surprise people with their area. Both sides of a 100 foot run of 6 foot fence is 1,200 square feet of wood, more surface than most decks and about the same as one wall of a two story house. That is why the honest planning answer is to break a fence into sections over a couple of weekends rather than promising yourself an afternoon.
Estimate your own run in the fence calculator, then get the time from the pressure washer PSI calculator.
On this page
What PSI do I need to clean a wood fence?
| Setting | Wood fence |
|---|---|
| Pressure | 500 to 1,200 PSI |
| Softwood pickets (pine, cedar, treated) | 500 to 800 PSI |
| Minimum flow | 1.2 GPM |
| Nozzle | 40 degree |
| Distance from the surface | 12 to 18 in |
| Cleaning rate | About 3 sq ft per minute for each 1 GPM |
| Area to plan for | Length x height x 2 sides, so 100 ft of 6 ft fence is 1,200 sq ft |
| Watch for | Gouged pickets, raised fibers and blasting soil into the bottom boards |
Work with the grain from top to bottom. Let the wood dry for a couple of days before staining or sealing.
Which nozzle should I use on a fence?
| Tip | Color | Use on a fence |
|---|---|---|
| 40 degree | White | The working tip for pickets, rails and posts. Wide fan, constant motion. |
| 65 degree or soap | Black | Applies wood cleaner so the chemistry removes gray weathering and mildew. |
Narrow tips carve grain lines into soft pickets within a second, and a 0 degree tip is never used on wood. If a board does not come clean at 40 degrees, the answer is cleaner and dwell time, not a narrower tip.
How long does it take to pressure wash a fence?
Fence area counts both sides. A 6 foot fence gives 12 square feet of board for every linear foot of run.
| Fence run, both sides | Board area | 1.2 GPM | 1.5 GPM | 2.0 GPM |
|---|---|---|---|---|
| 50 ft of 6 ft fence | 600 sq ft | 167 min | 133 min | 100 min |
| 100 ft of 6 ft fence | 1,200 sq ft | 333 min | 267 min | 200 min |
| 150 ft of 6 ft fence | 1,800 sq ft | 500 min | 400 min | 300 min |
| 200 ft of 6 ft fence | 2,400 sq ft | 667 min | 533 min | 400 min |
Minutes = area divided by (GPM x 3 square feet per minute per GPM), the same formula the pressure washer PSI calculator uses. Heavy staining, mildew and detergent dwell time add to every figure, and a pass with detergent plus a rinse pass doubles the wand time.
How do I pressure wash a fence step by step?
- Check the fence is sound. Push on posts and pull on loose pickets. A washer will finish off a rotted board or a wobbly post, so repair first.
- Cut back plants and cover beds. Trim vines and shrubs off the boards, move pots and give the beds along the fence a soak with plain water.
- Apply wood cleaner. A cleaner made for weathered wood lifts the gray surface layer and mildew that pressure alone would have to tear off.
- Wash top to bottom, with the grain. Hold the 40 degree tip 12 to 18 inches away and follow each board along its length. Start the spray off the board and sweep onto it.
- Keep the wand out of the dirt. At the bottom rail, angle across rather than down, or you will blast soil and mulch up the clean boards.
- Let it dry before you stain. Give the fence a couple of dry days. Stain on damp wood can cloud or peel, and sealing wet boards traps moisture inside them.
Should I pressure wash a fence before staining?
Clean it, yes; strip it with pressure, no. Stain sticks to sound wood, not to mildew, pollen film or a loose gray surface layer. Wood cleaner does that work with dwell time, and a low-pressure rinse carries it off. Where pressure goes wrong is fuzzing: raised fibers soak up stain unevenly and leave a blotchy finish that has to be sanded back.
Apply cleaner and finish with a sprayer rather than the washer. The Chapin 25012 Clean N Seal 1-Gallon Deck Sprayer is made for cleaners and transparent stains, and Wet & Forget Outdoor Cleaner Concentrate (128 oz.) is a no-rinse option for fence sections that green up in shade every year. Decks follow the same rules, which is covered in what PSI a wood deck takes, and if your fence is vinyl rather than wood, use the gentler numbers on vinyl siding.
Which pressure washers suit a wood fence?
Low pressure, decent flow, and a hose long enough to walk the run. Full picks are in the best electric pressure washers.
Kärcher K 5 Premium Electric Pressure Washer with Hose Reel
$386.01The onboard hose reel and 25 foot hose make repositioning along a fence line quick, and Vario Power keeps pressure at the softwood end of the range.
Best for: property lines of 100 feet and up
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Greenworks 2000 PSI 1.2 GPM Electric Pressure Washer
$194.99PWMA-rated 2,000 PSI and 1.2 GPM with auto stop and an onboard soap tank for wood cleaner. Quiet enough to work a shared fence line without annoying a neighbor.
Best for: suburban fence lines close to houses
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Sun Joe SPX3000 Electric Pressure Washer
$169.00Five tips including 40 degree and soap plus two detergent tanks, so cleaner and rinse aid both stay loaded across a long session.
Best for: garden fences and small back yards
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Chapin 25012 Clean N Seal 1-Gallon Deck Sprayer
$29.99A pump sprayer for cleaners and transparent stains puts chemistry on evenly at zero pressure, which is what keeps fence boards from being fuzzed by a washer.
Best for: anyone cleaning and staining in the same season
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We did not test these products in person. Picks are researched from manufacturer specifications and owner manuals, engine and safety certifications where they apply, warranty terms, public recall records, and the recurring themes in verified owner reviews. We favor established brands with large review counts and parts support, match each pick to a real yard size or task, and place it in the tier where its price and capability actually belong.
Frequently asked questions
What PSI should I use on a wood fence?
About 500 to 1,200 PSI with a 40 degree tip 12 to 18 inches from the boards, and 500 to 800 PSI on soft pine, cedar or treated pickets. Work with the grain and keep the wand moving. If staining does not come off at that setting, apply a wood cleaner and let it dwell rather than moving to a narrower tip.
How long does it take to pressure wash a fence?
Longer than most people expect, because both sides count. A 100 foot run of 6 foot fence is about 1,200 square feet of board, roughly 333 minutes at 1.2 GPM and about 200 at 2.0 GPM. Plan it as two or three sessions, and remember that cleaner dwell time and a separate rinse pass add to those figures.
Can I pressure wash a fence I share with a neighbor?
Talk to them first, both for access to the far side and because overspray, detergent and blasted grit end up in their yard. Cover or move anything of theirs close to the fence, wet their plantings before and after, and agree a time. If the fence itself is shared property, agree on any repairs before you start.
How long should a fence dry before staining?
A couple of dry days is the usual guidance, and longer in humid weather or heavy shade. Boards can feel dry on the face while the core is still wet, and stain over damp wood can cloud, peel or trap moisture. Sprinkle water on a board: if it beads rather than soaking in, the wood is not ready for finish.
Researched, not professional advice. This page is compiled from published specifications, manuals, labels and owner-review consensus, not hands-on testing. Follow the manufacturer's instructions and product label, and consult a qualified professional where safety, chemicals, fuel or structures are involved. As an Amazon Associate we earn from qualifying purchases.