How to Power Wash Your House

Your home's exterior is exposed to sun, wind, pollutants, dirt, and even bugs and animals. These elements take their toll: Over time, you'll notice that your siding, deck, or driveway has become discolored or damaged. Luckily, there's a solution. Power washing your house is an easy way to boost its curb appeal, prime surfaces for painting, prevent damage, and bring the façade back to its original glory. To help you do just that, we asked Lowes Project Expert Hunter Macfarlane and Brian Manke, the product manager at Stihl, to share exactly how to power wash your house.

Understand how to choose the correct power-washer.

Few household tasks are as satisfying as brandishing a powerful spray nozzle to quickly blast away dirt and deep-clean your exterior walls, deck, and driveway. Start by considering the project at hand, says Manke. If there's minimal buildup—or you're washing wood, which can get etched by a jet that's too strong—choose an electric model with a PSI (pounds per square inch) of around 2,000. To remove more set-in stains or mold, or tackle an entire house, go with a gas-fueled type with a PSI of 2,500 to 3,000.

Purchase your tools.

You may think that you need to hire a professional to power wash your house—and depending on the size of the job, you might want to do so—but Macfarlane assures us that this is a task most homeowners can tackle. To get started, here's what you'll need: a pressure washer, a hose, detergent, and drop cloths. Protective gear is critical, too, says Manke, who advises wearing nonslip work boots and safety goggles (debris can ricochet); if your machine is gas-powered, pop in earplugs to muffle the noise. Whether you decide to purchase or rent the necessary equipment (that's an option, too!), carefully read the documentation that comes with your machinery. "Take the time to learn how to set up your machine and how to select the correct spray pattern," Macfarlane says. "Settings often vary by detergent application or high-pressure cleaning."

Check your paint type.

Before you begin power washing, avoid a potential health risk by checking that your exterior is not covered in lead paint; applying forceful pressure can break up and spread pieces of this paint, which would be be harmful to your family. If you think your home might have a lead-based paint, Macfarlane recommends buying a test kit or working hiring a professional for an inspection.

Do the prep work.

Prep your work area by making sure all doors and windows are closed; it's also important to turn off the power to external electrical outlets, which should be covered with tape and plastic. Trim back plants and shrubbery that might get in the way, too. "Once you've prepped the area, start by testing the high-pressure spray on an inconspicuous spot to make sure the setting does not damage the exterior surface," Macfarlane suggests. Manke agrees, noting to first check the water supply by connecting an unkinked three-quarter-inch garden hose to ensure your unit receives sufficient flow to do its job right.

"Cleaning tough stains and grime on your home exterior may first require a detergent—you'll use a low-pressure spray pattern to apply this," Macfarlane continues. If you use a detergent, let it sit on the surface for a few minutes and then work the pressure washer from top to bottom in small sections. If you have a two-story home, he recommends getting spray tips and extensions to make sure you can reach the areas that are higher up.

Work the angles.

The widest nozzle draws detergent from the receptacle; if you're washing a vertical surface (like a wall), go from bottom to top. To power-rinse, switch to the 25-degree nozzle (green) and sweep it from the top down in overlapping passes, avoiding windows and frames. Use the more forceful 15-degree (yellow) one for stub-born regions, and the gentler 40-degree (white) one for soft materials like wood.

Aim high.

To reach places over-head, plug a lance extension into your machine rather than using a ladder. "The kickback could easily knock you right off of it," Manke explains. If you still can't hit the mark, hire a pro, who can do the job safely with scaffolding.

Take a different approach with lower-to-the-ground details.

To power-wash your porch, deck, driveway, or sidewalk, use a rotary surface-cleaner attachment—which looks like a frisbee and sprays water in a spinning motion—for fast and even cleaning.

Avoid windows and vents.

Keep in mind there are some areas you'll want to avoid when power washing your house. "Regardless of the type of exterior you're cleaning, avoid getting detergent or water behind the outer surface," Macfarlane explains. "Keep the high-pressure spray away from windows and exterior vents." He also advises standing on a stable surface and wearing safety protection equipment; never leave the spray gun unattended while the power washer is running, he adds.

Get yourself on a schedule.

How often should you give your home's exterior a deep clean? According to Macfarlane, you shouldn't need to power wash your house more than twice a year—but there is one spot in particular to keep a close eye on. "The northern exposure of a home is more prone to a buildup of moss and lichens because the area receives less direct sunlight, which may need more frequent power washing," he says.