Power Wash Exterior

If your home exterior can use a refresh, it's time to get out the power washer. While you can do this yourself, to make sure it's done correctly without damages, consider hiring a professional. The average cost to hire a power washing service is around $250.

Follow these simple steps to power wash your home's siding.

• Cover nearby plantings with a plastic drop cloth. Wet down plants that can't be covered and try to keep them wet.
• Mildew spots usually require a weak bleach solution. Wipe it on lightly, then rinse the area with clean water.
• To add detergent to the flow, hook the siphon tube to the pump with the filter end in the detergent container.
• Apply the detergent at low pressure. Work from the bottom up and allow the solution to stand several minutes.

Getting Started

In most cases, you'll want to soap your siding before washing it. All general-purpose washers have detergent attachments. Electric models usually have internal reservoirs, while gas models generally have siphon tubes that you insert directly into a container of detergent. As the detergent is pulled through the system, it mixes with water to make an approximately 12% solution, suitable for most applications. Because detergent needs extended contact to work effectively, it can be applied only when the machine is in its low-pressure mode. High pressure would blast it off as fast as it was blown on. We chose Campbell Hausfeld's General Purpose Cleaner (No. PW0051.) Detergents can pose a problem, however, especially if they contain bleach. Houses are surrounded by grass and landscape plantings, which can be damaged by such chemicals. Root systems can survive quite a bit, but the foliage is another story. To prevent leaf damage, choose a general-purpose cleaner that does not contain bleach. Then, cover landscape plantings with inexpensive plastic drop cloths. Thoroughly wet any plants you can't cover with plastic. Of course, if your siding is only a little dusty, it may not need a detergent.

If some of your siding has begun to grow mildew, however, a little bleach is required. Mix one part household bleach with 10 parts water and wipe it on the affected area. Then, rinse it away with a sponge and clean water. Using bleach on siding is tricky, so start with as little as possible, for as short a time as possible.

For a larger mildew problem, you might try Jomax, available in paint stores This mildewcide concentrate requires you to add bleach to the solution, but it deactivates the bleach after it's applied. Therefore, Jomax is said to be harmless to plants and paints. Spray it on sparingly with a garden sprayer.

With the mildew problem handled, you're ready to wash the rest of the siding. Begin by connecting a garden hose to the washer's pump. Then, turn the water on full bore. Next, set the detergent container next to the washer and slide the open end of the plastic siphon tube over the brass nipple on the underside of the pump. Feed the filtered end of the tube into the detergent container. Finally, slide the spray nozzle forward on the gun, switching from high to low pressure for the soap application. The nozzle can also be rotated to adjust the width of the pattern in the high-pressure mode.

With the water to the pump turned on, start the gas motor and, within a minute of starting, begin to spray an area of the house with detergent, working from the bottom up. The size of the area will depend on weather conditions, especially high winds. You won't want the detergent to dry on the siding before you can wash it off, it's best to keep the size of the area manageable. Allow the detergent to work on the siding for at least 2 to 3 minutes. While the solution works on the grime, remove the siphon tube from the pump. Switch the nozzle to high pressure and rinse the soap from the siding, using a wide spray pattern and holding the nozzle about 18 in. away from the siding. Again, work from the bottom up, without actually spraying upward.

Finally, working from the top down, rinse the siding thoroughly. This time hold the gun about 10 in. from the siding and spray at a downward angle. If you see spots that won't come clean, try moving the nozzle a little closer to focus the pressure. Watch the siding closely, however. Too much pressure can do real damage. Remember to avoid spraying electrical components directly. Spray carefully around doors and windows, angling the nozzle down and away. Move around the house in this fashion until you've finished the job.