How to Clean Concrete With a Pressure Washer

On this page (11 sections)

1. How do you prepare concrete before pressure washing?
2. How long after pouring can you pressure wash new concrete?
3. What pressure and nozzle should you use on concrete?
4. How do you wash concrete without leaving stripes?
5. Should you use a surface cleaner on concrete?
6. Which pressure washer handles concrete cleaning well?
7. How do you remove oil, rust and moss stains from concrete?
8. How do you protect plants and manage runoff?
9. How should you care for the washer after cleaning concrete?
10. What mistakes damage concrete when pressure washing?
11. How do you clean concrete with a pressure washer and get a clean result?

Clean concrete with a pressure washer by pretreating stains, using a wide fan tip or surface cleaner, and working in overlapping strips from dry to wet. Keep the tip moving, rinse the whole slab at the end, and let it dry before judging the result.

Concrete is hard and porous, so it holds dirt in its texture. Pressure washing lifts that dirt fast, but the same force can etch lines and pits if you hold the tip in one place.

A steady pace and the right attachment matter more than raw power.

How do you prepare concrete before pressure washing?

Clear the slab, sweep it, and pretreat stains before the wand comes out. Preparation separates a clean driveway from one with striped patches.

Move cars, planters and toys off the concrete. Sweep off leaves and loose grit so the water doesn't push debris into corners or drains.

Cover nearby plants and check that runoff flows away from the house. Water carries dirt and cleaning products, so keep it out of storm drains where local rules restrict it.

Treat oil, rust and moss spots first. A degreaser or concrete cleaner needs a few minutes to soften the stain.

Scrub tough spots with a stiff brush, then rinse lightly.

Check cracks and joints. A narrow tip aimed at an open crack can widen it.

New concrete needs the longest wait of all.

How long after pouring can you pressure wash new concrete?

Wait at least 28 days after a new slab is poured, and use low pressure when you start. Water forced into curing concrete can weaken the top layer.

Curing concrete gains strength slowly. The first week is the most fragile, but full cure takes about a month.

If the slab must be cleaned sooner, use a garden hose, a soft brush and a mild cleaner.

Even after a month, start gentle. New concrete has a smoother finish than aged concrete, so it shows marks easily.

Keep the fan tip wide and the pressure low for the first pass.

Ask the contractor who poured the slab if you aren't sure when it was placed. Stamped concrete and exposed aggregate need extra care because their patterns and texture hold both dirt and water.

What pressure and nozzle should you use on concrete?

Use a 25- or 40-degree fan tip and keep pressure moderate for most driveways. A 0-degree tip is the wrong choice for concrete, no matter how stubborn the stain looks.

The 0-degree nozzle sends water into a point smaller than a coin. Held still, it can carve a visible line into concrete in seconds.

A 25-degree tip spreads the stream enough to clean without concentrating the force.

Start at a low setting if your washer has one. Move up only if the dirt doesn't lift.

The right working distance keeps the spray pattern visible and the water moving in one direction.

Match pressure to the slab's age and finish. Old, hard, dirty concrete tolerates more.

Smooth or decorative concrete needs less. A machine rated around 2,000 to 3,000 PSI handles most home jobs.

Check our guide to the best pressure washers for driveways and concrete if you're still choosing a machine. A budget pressure washer can handle light jobs on smaller slabs.

How do you wash concrete without leaving stripes?

Work in overlapping strips and keep the wand moving at a steady speed. Stripes come from uneven passes, not from the concrete itself.

Pick a starting edge and push the wand away from you in a straight line. Overlap each pass by about half the spray width so no dry strip is left between them.

Move at a consistent pace. Stopping to chat or check your phone leaves a mark where the water sits.

If you must pause, lift the wand off the surface.

Rinse the whole slab at the end with a wide fan on low pressure. A final rinse washes loosened dirt toward the edge or drain instead of letting it dry back onto the surface.

Let the concrete dry completely before you judge. Wet concrete hides dirt and shows dark streaks, so the surface looks worse until it dries.

Should you use a surface cleaner on concrete?

Yes, a surface cleaner is the faster, more even way to clean flat concrete. It covers more area per pass and reduces the stripes a hand wand can leave.

A surface cleaner uses a spinning bar with two jets under a round housing. The water hits the slab evenly as you push the unit.

Edges, steps and tight corners still need the wand.

The Westinghouse 16.5-Inch Surface Cleaner is a stainless steel attachment rated to 4400 PSI with a 1/4 inch quick connect. Its 16.5 inch cleaning area suits decks, patios and driveways, and the connector fits most gas and electric washers.

It's a good starting point for a homeowner cleaning one or two slabs.

If you want to cover a large driveway with less pushing, the MEKOH 20-Inch Surface Cleaner has a wider 20 inch housing and four wheels. Its two spinning nozzles are built for streak-free cleaning, and the dual handles let you push it back and forth.

It needs a washer with at least 2000 PSI and 2 GPM.

Skip a surface cleaner if your concrete is mostly steps, curbs or narrow paths. A fan tip on a hand wand reaches those areas better.

Which pressure washer handles concrete cleaning well?

An electric washer in the 2,000 to 2,300 PSI range is enough for most home concrete jobs. Gas models add power for large or heavily stained slabs.

The Westinghouse WPX2300e delivers 2300 max PSI and 1.76 max GPM at its lowest pressure setting, with 1900 rated PSI. It has a 25 foot hose, a 0.42 gallon soap tank and five quick connect nozzles.

That soap tank helps when you want to apply a cleaner before the rinse pass. It's a practical match for a driveway or patio job.

For a larger slab or a machine you'll use on other jobs, our roundup of electric pressure washers compares the options. A budget pressure washer covers small patios and walkways without overspending.

How do you remove oil, rust and moss stains from concrete?

Treat each stain type with the right product before pressure washing. Pressure alone drives some stains deeper instead of lifting them.

Oil stains: apply a degreaser or absorbent powder, let it sit, then scrub and rinse. Rust marks: use a rust remover made for concrete.

Moss and algae: kill the growth first, then wash it away.

Apply cleaners with a pump sprayer or the washer's soap tank on low pressure. Let the product dwell as the label directs, then rinse with a wide fan tip.

Keep runoff away from plants and follow local rules for outdoor cleaning products.

Don't mix cleaners. Some combinations release fumes, so use one product at a time and rinse between them.

How do you protect plants and manage runoff?

Cover or wet plants, direct water away from drains, and keep cleaning products out of storm sewers. Runoff carries dirt and chemicals, and many areas restrict what can enter drains.

Wet nearby plants before you start so they absorb plain water first. Cover sensitive shrubs with plastic sheeting or move pots off the concrete.

Use a squeegee or a broom to push dirty water toward a lawn or a drain allowed by local rules. A wet-dry vacuum can pick up standing water in low spots.

Keep the cord and outlet dry if you're using an electric washer. A GFCI cord protects against shock, but water and electricity still need distance.

How should you care for the washer after cleaning concrete?

Rinse the wand and surface cleaner, flush the soap line, and store the machine dry. Concrete grit wears nozzles and seals faster than clean water does.

After the job, run clean water through the soap tank and line to clear any cleaner. Wipe the housing and nozzles, and check for grit stuck in the spray openings.

Drain the hose and coil it loosely. Store the washer indoors where it won't freeze.

If you clean late in the season, read how to winterize a pressure washer before the first hard frost.

Check the nozzle tips for wear. A worn tip sprays unevenly and leaves streaks, so replace any that look damaged or clogged.

What mistakes damage concrete when pressure washing?

The main risks are too much pressure, a narrow tip held in one spot, and washing too soon after a pour. Each one leaves marks that are hard to undo.

Cleaning in full sun so the cleaner dries too fast, skipping the final rinse, and letting dirty water dry back onto the slab all leave a dull film or streaks. Avoid tipping the wand toward joints and cracks, where driven water can widen the gap over time.

Decorative concrete needs the gentlest approach, because high pressure can erase the finish.

How do you clean concrete with a pressure washer and get a clean result?

The recipe is simple: prepare, pretreat, use a wide tip or surface cleaner, work in strips, and rinse. Keep pressure moderate and let the concrete dry before you judge the job.

Choose the MEKOH 20-Inch Surface Cleaner for a large driveway where coverage matters, the Westinghouse 16.5-Inch Surface Cleaner for a standard slab, or the Westinghouse WPX2300e if you still need a washer with enough power and a soap tank.

Skip the 0-degree tip on concrete and skip pressure washing a slab poured in the last month. Those two shortcuts cause most of the damage.

When you're done, hose off the equipment and store it dry so the next job goes just as smoothly.

Frequently asked questions

What pressure is safe for cleaning concrete?

Most driveways and patios clean well at 2,000 to 3,000 PSI with a wide fan tip. Old, hard concrete handles more, while new or decorative concrete needs lower pressure and a longer dwell time.

Test a hidden patch first.

Can I use a 0-degree nozzle on concrete?

No, avoid the 0-degree tip on concrete. It focuses water into a tiny point that can etch lines and pits into the surface in seconds.

Use a 25- or 40-degree fan tip, or a surface cleaner that covers the slab evenly.

How long should concrete dry before you judge the cleaning?

Wait until the concrete dries fully, usually a few hours in sun and longer in shade. Wet concrete hides dirt and shows dark streaks.

Some marks fade further over a day or two as surface moisture leaves.

Does a surface cleaner work better than a nozzle on concrete?

A surface cleaner covers flat concrete faster and leaves fewer stripes than a hand wand. It spins two jets under a housing so the water hits the slab evenly.

Handheld tips still work best for edges, steps and tight corners.