How to Clean Patio, Pavers, and Outdoor Furniture with a Pressure Washer

My First Pressure Washer Mistake Cost Me $400

I etched a giant zigzag pattern into my brand-new concrete patio. Permanent. Like a scar from a bad tattoo. I was 18, cocky, and thought "more pressure = cleaner faster." Wrong. The patio looked like a Jackson Pollock painting made with a sandblaster. I had to resurface the whole thing. Don't be me.

Since then, I've cleaned dozens of driveways, patios, and furniture sets. I've gone through three pressure washers and a lot of shame. Here's exactly how I'd clean your stuff today, including the mistakes I won't make again.

Tools and Stuff You Actually Need

Let's be real about gear. You don't need a $800 machine for a patio. But the $99 electric box from a big box store? That's a toy. It'll take you all day.

• Pressure washer: I run a 2,700 PSI gas unit with a 2.3 GPM flow rate. That's the sweet spot. Gas means no extension cord tangles. For electric, 1,800 PSI minimum, and 1.4 GPM or higher. Anything less and you'll just spray soap around.
• Surface cleaner attachment: This is a disc-shaped thing with spinning jets. I can't recommend this enough. It costs about $60–$100 and saves your back. Without it, you'll leave tiger stripes.
• Nozzles: You'll get a set. The green 25-degree nozzle is your general cleaner. The yellow 15-degree is for tough stains on concrete. Never use the red 0-degree. That's the one that dug a groove in my patio.
• Chemicals: Buy a dedicated concrete cleaner from a hardware store. Not dish soap. Simple Green Pro HD or Zep Concrete Cleaner — about $15 a gallon.
• Furniture protectant: After cleaning, hit metal frames with Boeshield T-9 or WD-40 Specialist. About $12 a can.
• Gloves + eye protection: I learned this the hard way. Pressure washer cuts skin like a chainsaw. Don't be a hero.
• Soft brush: A plastic bristle brush for furniture. Not a wire brush — that scratches aluminum frames.

Prep Work That Saves Your Butt

First, sweep everything. Get the leaf mulch, dirt, and dog hair off. Wet the whole area with a hose. This keeps chemicals from drying out too fast.

Move all furniture off the patio. I once cleaned around a heavy table because I was lazy. The dirt line under it is still there. It looks stupid.

Check for loose pavers or cracked concrete. If there's a cracked piece, don't blast it with high pressure. You'll blow chunks out. I did that on a client's driveway. He was not happy.

Cover nearby plants with a plastic tarp if you're using chemicals. Your roses don't need a bleach bath.

Step by Step: Cleaning Patio and Pavers

Step 1: Apply cleaner.

Mix your concrete cleaner per the bottle. Usually 1 part cleaner to 4 parts water. Spray it on with a garden sprayer. Let it sit for 5–10 minutes. Not longer — it dries into a crust and you'll have to scrub.

Step 2: Use the surface cleaner.

Attach the surface cleaner to your wand. Set the nozzle to green (25-degree). Start at the farthest corner of your patio and work toward your exit. Overlap each pass by about 6 inches. Move slow and steady. The dirt lifts off like magic.

For pavers, the joints (sand gaps) will spit sand everywhere. That's normal. You'll have to resand later. Keep moving — don't hover over one joint or you'll blow a crater.

Step 3: Edge work.

The surface cleaner can't reach edges. Switch to the yellow 15-degree nozzle. Stand back about 18 inches from the edge and spray at a 45-degree angle. Don't get close. I got close once and now my garage foundation has a clean 1-inch trough.

Step 4: Rinse.

Switch to the green nozzle and spray everything down. Work from the top down. Get all soap off, or it'll leave white residue. I rinse twice — once with high pressure, once with just the hose.

Step 5: Let it dry.

This takes 4–6 hours in direct sun. Pavers will look light gray when dry. They might look blotchy while wet — don't panic.

Step 6: Resand pavers (if needed).

Once dry, spread polymeric sand over the joints. Sweep it in, then mist with water. Let it harden for 24 hours. This keeps weeds out.

How I Clean Outdoor Furniture Without Ruining It

This is where most people screw up. They blast the hell out of a plastic chair, and it cracks. Or they hit aluminum, and the paint peels off like a sunburn.

Plastic/resin furniture: Set the pressure to 1,000–1,200 PSI if your machine has an adjustable regulator. Otherwise, use the white 40-degree nozzle (lowest pressure). That's gentle enough. Spray from 2 feet away. Clean with a soft brush first if there's bird poop. Don't try to blast it off — you'll leave a divot.

Metal (aluminum, steel): Use the green 25-degree nozzle at 1,500 PSI. Keep the nozzle moving. If you stop, you'll strip paint. For rust spots, hit them with the yellow nozzle briefly, then sand and repaint later.

Wood (teak, cedar): This is tricky. Don't use high pressure at all. I cap my machine at 1,000 PSI. Use the white nozzle. Keep your distance — at least 3 feet. You're basically wetting it down and using a deck cleaner. Scrubbing with a soft brush is safer. I've seen guys blow grooves into teak slats. Looks awful.

Cushions: Take them off the frame. Spray with a garden hose first. Use a gentle soap (like Woolite) and a soft brush. Rinse with a hose at low pressure. Never pressure wash fabric. It'll shred the fibers. I learned this on a $300 set of cushions. They looked like frayed rope after.

Three Mistakes I Still See People Make

1. Using too narrow a nozzle on concrete. That red 0-degree nozzle is a cutting tool. It's for stripping paint off metal, not cleaning your walkway. I've seen guys etch their driveway numbers into the concrete. Literally.

2. Not overlapping strokes. If you just sweep back and forth without overlap, you'll get stripes — dark spots where you missed, light spots where you hit hard. Overlap 50% of your last pass. It feels repetitive, but it's the only way to get even color.

3. Cleaning in direct sun. I did this once. Spent the whole day on a south-facing patio. The cleaner dried in 4 minutes. I had to scrub dried soap crust off with a brush. Now I start at 7 AM or wait for a cloudy day. Takes me 2 hours for a 500 sq ft patio that way. In sun, it took me 4 hours.

Quick Lessons on Technique

Hold the wand with both hands. Seriously. The kickback from a gas washer can snap your wrist if you're not ready.

Walk backward while spraying. This keeps your shoes out of the puddle of mud you just created. You'll track less dirt back onto clean concrete.

Don't push the machine closer than 6 inches to any surface. That's too close unless you're using the white nozzle. Distance is your friend.

FAQ

How do I get rid of black algae spots on my patio?

That's usually from shade and moisture. I spray a 50/50 mix of bleach and water on the spots, let it sit 10 minutes, then use the surface cleaner. Don't use pure bleach — it kills grass. Rinse the whole area after. I've done this on 5 patios, and it works every time.

Can I use a pressure washer on paving stones?

Yes, but you'll blow out the sand joints. That's why I suggest a surface cleaner — it's gentler on the joints than a direct spray. Plan on resanding after. If you don't, ants will move in within a week.

What pressure should I use for furniture?

Under 1,500 PSI for metal and plastic. Under 1,000 PSI for wood. Most electric washers run around 1,600 PSI, so you're fine if you keep the nozzle back 2 feet. Gas washers — you'll need to buy a pressure regulator tip. I use one that caps output at 1,200 PSI. Costs about $25 online.

How often should I clean my patio?

I do mine every spring and fall. That keeps moss and dirt from building up. If you live in a wet climate, maybe three times a year. Don't let it go 5 years — the dirt embeds into the pores and you'll need a harsh acid wash to get it clean. I helped a neighbor once whose patio was so old it had soil buildup. Took 3 passes to get it back to gray.

Is a pressure washer worth renting?

For a one-time job? Yes. Rent a 2,500 PSI gas unit from a rental place for about $60 for 4 hours. That's cheaper than buying a new one. But if you have a big property, just buy a decent electric washer. I use a Ryobi 1,800 PSI for my deck, and it's fine. It won't strip paint, but it still cleans.