ConsumerReports article.
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How to choose
Last reviewed: August 2011
Today's pressure washers cost as little as $90 for corded electric models and $300 for gas-powered machines, making both a tempting alternative to the $50 to $90 per day you'll spend to rent one.
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 kind of power blasts away deck mildew, driveway stains, and other grunge a hose couldn't touch. Lower prices and less upkeep are why 60 percent of buyers choose washers with an electric motor. But gas models have roughly twice the cleaning power-a key reason you'll see fewer plug-ins at the big-box stores that account for the most sales.
What's available
Models from Black & Decker, Campbell Hausfeld, Craftsman, Excell, Honda, Husky, Karcher, and Troy-Bilt are among the brands you'll find.
Gas-powered washers
These are 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. 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.
Electric washers
These are 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.