Renting a pressure washer for the house: what you can do yourself and where to stop

Yes for plain concrete, no for the house itself

You can reasonably pressure wash a plain, sturdy concrete driveway or sidewalk yourself if you are careful and wear the right gear. You should not point a rented pressure washer at stone, stucco, painted siding, brick with soft mortar, wood you plan to keep, or the roof, because the force that cleans concrete pits, strips and gouges those surfaces permanently. For the house itself, the safer method is a low-pressure soft wash with a cleaning solution, which is a different tool and a different skill.

I run Park Cities Power Wash, and I am not going to pretend nobody should ever own a pressure washer. Plenty of homeowners do a fine job on their own driveway. But a good part of our work is repairing the look of surfaces that someone damaged trying to save money, and the damage is almost always on the same handful of materials. This guide tells you which jobs are fair game, which ones to leave alone, and how to stay safe if you do pick up the wand.

What a rented machine is actually putting out

Most people underestimate the force. Our soft washing article notes that rented gas pressure washers often run 2,800 to 3,400 PSI, while the soft washing we use on delicate surfaces runs under roughly 500 PSI, with the cleaning solution doing the work instead of the water. That gap is the whole story. Concrete is dense enough to take high pressure; porous stone, stucco and paint are not.

A Mississippi State University safety newsletter on pressure washers puts it vividly: some nozzles are designed to blow paint off concrete, so imagine what they do to skin. The same force that removes grime from a driveway will etch soft limestone, open hairline cracks in stucco and drive water behind siding. The marks you make in the first five minutes are often still there years later.

Jobs a careful homeowner can handle

If you want to do some of the work yourself, start with the surfaces that forgive mistakes. Plain broom-finished concrete is the obvious one. A flat surface cleaner attachment, which looks like a spinning disc on wheels, gives far more even results than a wand and avoids the striping that comes from sweeping the nozzle back and forth.

A few habits make the difference between a clean driveway and a striped one. Sweep first so you are not grinding grit into the surface. Move the cars, bins and anything you do not want soaked. Work in overlapping passes at a steady speed, keep the surface cleaner flat, and rinse toward the street rather than toward the garage or the flower beds. On a hot Dallas afternoon, any detergent you use can dry on the concrete before you rinse it, so early morning is the better time to work.

Keep your expectations realistic. Pressure alone removes the visible growth, but our soft washing article explains that the roots remain and growth returns sooner than it does after a treatment that kills it. Oil, rust and the orange tannin stains that fall from pecan and oak trees usually do not come out with water alone, and I cover what does remove them in rust, oil and tree stains on the driveway.

• Plain broom-finished concrete driveways, sidewalks and garage aprons.
• Outdoor trash can areas and plain concrete pads.
• Plastic patio furniture and garbage bins at low pressure.
• Concrete steps, curbs and the slab around an outdoor faucet.

Surfaces where DIY does lasting harm

These are the surfaces that show up in our calls after a weekend project. On each of them, the visible damage is permanent: you cannot press the surface back into place.

The limestone and Austin stone on many older homes in the Park Cities and the surrounding neighborhoods is the material we see damaged most often, because it is soft, porous and expensive. Pressure does not just remove the algae; it removes a thin layer of the stone with it. The surface that is left is rougher than before, so it holds dirt and spores faster, and the cleaned patch often looks lighter and blotchier than the rest of the wall.

If your main concern is algae on stone, read what is growing on green and black stone and how it comes off before you try anything. And if you are not sure which category a surface falls into, soft washing versus pressure washing, surface by surface goes through each one.

• Austin stone, limestone and cast stone: pitting, etching and a blotchy surface that holds dirt even faster.
• Stucco and EIFS: opened hairline cracks and water forced behind the finish.
• Painted siding and trim: stripped or lifted paint, and water pushed behind panels.
• Older brick: mortar blown out of the joints.
• Wood decks and fences: raised, furry grain and gouges from a narrow tip.
• Asphalt shingle roofs: stripped granules that shorten the roof's life.
• Windows and their seals: broken seals, water inside and damaged screens.

The roof is a hard no

Of everything on that list, the roof is the one I would underline. The Asphalt Roofing Manufacturers Association states plainly that a power washer, brush or broom should not be used to clean algae from a roof, because high-pressure systems are likely to damage asphalt roofing. ARMA also encourages using professionals for shingle cleaning and recommends that only trained people work on roofs.

Add the ladder to the picture and the risk changes from cosmetic to physical. The Mississippi State newsletter warns against using a pressure washer on a ladder or at height, because the kickback can push you off balance. A wet roof coated in cleaning solution is slick. No streak is worth that fall.

If you do it yourself, do it safely

Pressure washer injuries are more serious than they look. The Mississippi State newsletter notes that high-pressure injection injuries may appear minor at first, which leads people to delay treatment and puts them at risk of infection, disability or amputation. It names the hand as the most common injection point and recommends safety glasses, gloves and enclosed shoes, never flip-flops.

The same newsletter suggests reading the manual front to back, avoiding rain and heavy wind, covering electrical fixtures and vents, and never running a gas machine in an enclosed space because of carbon monoxide. Start with the widest spray tip about two feet from a test area and adjust from there, rather than starting close and narrow.

• Safety glasses, gloves and closed work boots.
• Never point the wand at a person, a pet or your own feet.
• No ladders and no roofs with a pressure washer.
• Widest tip first, two feet back, on a hidden test spot.
• Gas machines outdoors only, never in a garage.
• Close windows, cover outlets and keep kids and pets inside.

The bleach-from-the-hardware-store problem

Some homeowners skip the pressure washer and reach for a pump sprayer and household bleach instead. That is closer to how soft washing works, and it can lighten algae, but the details matter. Professional soft washing pairs sodium hypochlorite with a surfactant so it clings to vertical surfaces, matches the strength to the material, and manages runoff with pre-wetting and a neutralizer on plants.

Without those steps, you often get a streaky wall, dead shrubs along the foundation and faded paint or trim where the mix was too strong. Our house washing page notes that for some paints the chemical step is skipped entirely because the finish is not compatible. That is a judgment you want made before anything is sprayed.

Doing the math on DIY

A rented machine looks cheap until you add the day it takes, the attachments, the fuel, the detergent and the learning curve. Our soft washing article puts it simply: a single wrong-pressure pass can erase any money saved. Replacing a section of etched limestone, repainting a stripped wall or replacing a roof early costs far more than a professional cleaning.

There is also the time cost nobody budgets. Washing a two-story stone exterior properly, with plant protection, the right mix for each surface and a thorough rinse, is a full day for someone who does it every week. For a first-timer it can easily stretch across a weekend, and the result is rarely as even.

A sensible split for many homeowners is to clean the plain concrete themselves and leave the house, the roof and any stone or painted surfaces to a company that soft washes. If you go that route, the questions to ask a pressure washing company before hiring will help you find one that actually protects those surfaces.

When it is time to hand it over

Call a professional if the dirt is on anything other than plain concrete, if you would need a ladder to reach it, if the growth has been there for years, or if the stain did not move with water and you are tempted to go closer and narrower. That last impulse is where most damage happens.

We clean homes within about 30 miles of Dallas, and simple jobs can be quoted from photos or satellite imagery. If you have already tried a section yourself and it did not go well, send us photos anyway. We will tell you honestly what can be improved, what cannot, and how to keep the rest of the house from going the same way.

Questions people ask me