Professional cleaning at a do-it-yourself price has helped move pressure washers beyond the tool-rental shop and into your local home center. Lower prices and less upkeep explain why 60 percent of buyers choose an electric pressure washer. But gas machines have roughly twice the cleaning power, which is the main reason you'll see fewer plug-in models at the big-box stores, where most pressure washers are sold.
Pressure washers use a gas engine or electric motor, pump, and concentrating nozzle to boost water pressure from your garden hose as much as 60 times. That lets them blast away deck mildew, driveway stains, and other grunge a hose can't touch while cleaning chairs, siding, and other items more quickly and easily than you could with a scrub brush. For as little as $90 for electric machines and $300 for gas, owning one is a tempting alternative to renting one for $50 to $90 per day.
Consumer Reports' previous tests of pressure washers on an array of outdoor surfaces confirmed that gas-powered machines have a clear performance edge over electrics. But more pressure also means more chance of injury with any pressure washer. Especially with gas models, it's easy to damage what you're cleaning. We're bringing in a new batch of pressure washers for testing to see if performance has changed.
Water pressure is typically measured in pounds per square inch (psi). Gas-powered models typically put out 2,000 to 2,800 psi of pressure compared with 1,300 to 1,700 psi for electric models. Much higher pressure allowed the top-performing gas machines to clean a grimy concrete patio three times faster than the fastest electrics. Gas models were up to 10 times faster at stripping paint off vinyl siding, a test we used to simulate tough stains.
On the downside, all of the gas models required more caution and control than the electrics to avoid splintering and etching wooden tables and other surfaces.
All the gas pressure washers produced at least 85 decibels (dBA), the threshold at which we recommend hearing protection. Electric models averaged 78 dBA when running and are silent with their triggers released, since doing so stops the motor.
Injuries involving pressure washers are estimated to affect more than 6,000, according to the Consumer Product Safety Commission. Typical mishaps include chemical burns to the eyes and skin abrasions. You can also be injured by material shot back at you. To protect yourself and what you're cleaning:
• Wear safety glasses or goggles, shoes, and, with gas models, hearing protection.
• Start with the nozzle 2 feet away from the cleaning surface and move closer as needed, but no closer than 6 inches.
• Set the nozzle to the widest spray angle that removes the stain.
• Practice first by cleaning a hidden area.
• Point the nozzle away from legs, feet, people, and pets, as well as lights, air conditioners, and other electrical devices.
• Be wary of using solid-stream nozzles and settings, which can cause the most harm.
You'll find models from Black & Decker, Briggs & Stratton, Craftsman, Excell, Homelite Husky, Karcher, and Troy-Bilt at home centers and dealers.
Best for: Quickly cleaning decks, siding, and other large areas as well as whisking away gum, sap, and tough stains. They pump out 2,000 to 2,800 pounds per square inch (psi) of water pressure vs. 1,000 to 1,800 psi for electrics, allowing gas models to clean a grimy concrete patio three times faster than the fastest electrics.
But: Downsides include added noise and weight, and the need for pull-starting, fuel-mixing, and tuneups. Pumps must be winterized with anti-freeze in colder areas, since gas machines shouldn't be stored inside a home. Gas models also require more caution and control than the electrics to avoid injuries and damaging wood and other soft surfaces. Price: $200 to $500.
Best for: Small decks and patios, furniture, and other lighter-duty jobs that emphasize cleaning over stain removal. They're relatively light and quiet, require little upkeep, and create no exhaust emissions. They start and stop with a trigger and are small enough to be stored indoors without winterizing.
But: Less pressure means slower cleaning. Wands and nozzles are less-sturdy plastic, not metal. And you need to be near an outlet. Price: $90 to $180.
A soap tank saves you the hassle of using separate containers. Tool and cord storage is a plus, as are wheels for heavier models. Adjustable nozzles are more convenient than replaceable nozzles; a twist changes spray width or pressure. But replaceable nozzles allow specific spray angles, broadening your options.
Practically any pressure washer can handle decks, walks, and other typical cleaning tasks. They're also forceful enough to harm a car's paint, which is why we suggest using a hose for cars.
Retailers and manufacturers often push lofty numbers for water pressure and volume. Some talk about "cleaning units," which are simply pressure multiplied by volume.
—Ed Perratore (@EdPerratore on Twitter)