How Often Should You Pressure Wash Your House, Driveway, and Deck?

Why I Finally Started Caring About Timing

I'll be honest with you. I didn't used to think about how often to pressure wash anything. I just grabbed my machine when the driveway looked gross or the deck felt slimy. That worked fine until the year I blasted a hole clean through my cedar siding because I waited so long the wood had rotted underneath the grime.

That repair cost me $400 and a weekend I'll never get back. So I started paying attention. I tested different schedules on my own house, my neighbor's place, and three rental properties I manage. Here's what actually works, based on real wear and tear, not some manufacturer's manual written by a guy who's never held a wand.

Your House Siding: Every 1 to 2 Years

Most houses need a wash every 12 to 24 months. Vinyl siding is the easiest. I run my machine at 1,200 to 1,500 PSI with a 40-degree nozzle. Any higher and you'll force water behind the siding. I learned that the hard way on my own porch — water got trapped, mold grew inside the wall, and I had to tear out a section of drywall. Don't be me.

If you live near a busy road, you'll need annual washes. The traffic film builds up fast. I have a buddy two blocks from a highway, and his house looks dingy after 8 months. Mine on a quiet street? I can push it to two years easy.

Brick and stone can go 3 to 4 years before they need a serious clean. But here's the catch — if you see white efflorescence (that chalky salt residue), don't wait. That means moisture is migrating through the brick. Clean it off with a low-pressure rinse and a masonry cleaner. I use Simple Green's Oxy Solve Total Outdoor Cleaner for brick. Costs about $12 a gallon and works better than bleach.

Wood siding is a different beast. You should wash it every year if you want to keep the paint from peeling. Use a 25-degree nozzle at 1,000 PSI max. And always spray at a downward angle so you don't force water up under the shingles. I watched my dad do it backward once and the water ran inside his laundry room.

Driveways: Every 2 to 3 Years — Unless You Park Like Me

For a standard concrete driveway, every two or three years is plenty. I do mine every 18 months because I park an old truck that leaks oil. But if you keep your cars clean and don't have a weeping transmission, you can stretch it.

I spent about 2 hours on my 500-square-foot driveway last spring. Used a 15-degree nozzle at 2,500 PSI with a surface cleaner attachment. That attachment was the best $80 I ever spent. Without it, I'd get those ugly circular marks from trying to sweep with the wand. I still have a few from the first time I tried — now they're permanent shadows in the concrete.

Here's when you actually need to scrub: if you see moss or algae growing in the cracks. That means the surface is porous and holding moisture. I scrub those spots with a stiff brush and a mix of water and bleach (one cup bleach per gallon of water). Let it sit 10 minutes, then rinse. Don't use full-strength bleach — I killed a patch of grass that way and had to resod a two-foot strip.

PSI warning for driveways: Don't go over 2,500 PSI on residential concrete. I borrowed a 3,500 PSI machine once and it etched the surface like coarse sandpaper. Now the driveway looks like it has road rash. Concrete is tough, but it's not bulletproof.

Wood Decks: Once a Year, No Exceptions

Decks are the most maintenance-heavy job on this list. I pressure wash my cedar deck every spring, right after the pollen settles. That's 12 months between washes. If you live in a humid area like the Southeast, you might need two washes a year. My sister in Florida does hers in March and August because the mildew grows that fast.

Here's the mistake I made on my first deck: I used a 0-degree nozzle. Don't do that. It gouged grooves into the wood that looked like a bear clawed it. I had to sand the whole 300-square-foot deck. Took me a whole Saturday and I was sore for two days.

Use a 40-degree nozzle at 600 to 800 PSI. Hold the wand about 12 inches from the wood. You want to remove the dirt, not the wood fibers. Spray with the grain. I know it's boring, but if you go cross-grain, you'll leave permanent scratch marks.

Let the deck dry for 48 hours before you stain or seal it. I rushed once and sealed in moisture. The stain peeled within three months, and I had to strip and redo the whole thing. A quart of stain is $30, but my time is worth more than that.

For composite decks (like Trex), you can go 2 to 3 years. But use even lower pressure — around 500 PSI. I saw a neighbor blast a groove into his composite board at 1,500 PSI. That board was ruined. He had to replace it.

Three Things I'll Never Do Again

• Pressure wash a roof. Even at low pressure, you can lift shingles. Water gets under them and you get leaks. I did this once and it cost me $1,200 in repairs. Use a soft wash system or pay a pro.
• Use bleach on painted surfaces. It'll strip the paint faster than a sandblaster. I tried it on my garage door and it looked like a zebra. Use a dedicated house wash detergent instead.
• Work from a ladder with a pressure washer. The kickback is real. I fell off the second rung of a stepladder chasing a stubborn spot. Broke my wrist. Now I use an extension wand from Amazon — $35 and it keeps my feet on the ground.

Frequently Asked Questions

What PSI do I need for most jobs?

For houses and decks, 1,200 to 1,500 PSI is plenty. For driveways, 2,000 to 2,500 PSI works. Anything over that is overkill for a homeowner. I use a 2,500 PSI electric washer from Sun Joe. It cost $130 and has lasted five years. Gas machines are more powerful, but they're heavier and louder. I don't think they're worth it unless you're cleaning a full concrete parking lot.

Should I hire a pro or do it myself?

If you have a single-story house with standard siding and a small driveway, do it yourself. You'll spend maybe $50 on a machine rental and $15 on detergent. You'll finish in half a day. But if your house is two stories or more, hire a pro. The risk of falling is real, and a pro's liability insurance covers any damage to your property. My friend's neighbor hired a guy who blasted a hole through his vinyl siding and the guy just drove away. So get a signed estimate and check their insurance.

What time of year is best?

Spring or fall, when temps are between 50 and 80°F. Direct summer sun dries the detergent too fast and leaves streaks. Winter freezing is dangerous because water left in the machine will crack the pump. I store mine indoors during winter with RV antifreeze run through the pump. Blew up two pumps before I figured that out.

Can I use just water or do I need soap?

For driveways, water is fine if you're just doing maintenance. But for houses and decks, use a detergent. Without it, you're just moving dirt around. I use Zep's Pressure Wash House Cleaner for siding and Thompson's WaterSeal Deck Cleaner for wood. Both are under $20. Don't use dish soap — it foams like crazy and can leave a sticky residue. I tried it once and my deck was slippery for a week.

How do I know when it's time to wash?

Look at your siding. If you see a green or black tint from algae, it's past time. Decks should be washed when the wood feels fuzzy or slimy to the touch. Driveways are ready when a water hose doesn't make them look cleaner. The real test is this: if you rub a finger on the surface and your finger gets dirty, grab your washer. That simple.

I keep a calendar reminder on my phone for each property. House in April, deck in May, driveway in October. I've been doing it that way for four years now and haven't had a single rot issue, a paint peel, or a stained surface. And more importantly, I haven't fallen off a ladder or ruined another piece of siding. Pressure washing is one of those rare jobs where a little planning actually saves you money. Most people skip it until the problem is obvious. By then, you're either scrubbing twice as hard or paying a pro to fix damage. A $20 bottle of cleaner and two hours on a Saturday is a lot cheaper than a new deck board.