Power washing your house every year with a high-pressure water spray can not only keep it looking good but can cut the need to repaint as often. Power washing aluminum, steel, vinyl or wood siding removes grit that grinds away the surface when it's agitated by wind or rain. Power washing is also a good way to prepare a house's surface for repainting, once the siding is clean you may find that you don't need to paint after all. If your house does need repainting, a thorough power washing removes dirt mildew, moss, peeling, flaking and chalking paint. You can wash a large house in a single day.

Power washers are available for rent from tool rental stores and some paint stores. Make sure someone demonstrates how the equipment works and answers all your questions before you leave the store. Power washers are rated by the pressure of their spray, measured in pounds per square inch (psi). For the average house, a rating from 1,200 to 2,500 psi, is sufficient. Less than 1,200 psi won't do the job effectively and more than 2,500 psi could do damage to your home. Power washing with clear water usually does the trick. But to remove chalking, moss or mildew, you'll probably need a general cleaning agent, available where you rent the equipment. Nozzle design and spray width are important. The recommended nozzle sizes are the 15 and 25 degree nozzles.

Power wash from the bottom up, to prevent dirt and the cleaning agent from running down and rinse from top down to wash away dirt and avoid leaving streaks.

Here are some tips: Always wear safety goggles to protect your eyes from splashback or accidental spray. Turn off the power to light fixtures and electrical outlets. Cover them with plastic bags secured with duct tape. Place drop cloths over plants and shrubs. Move lawn furniture away. Don't let children operate a power washer. Keep the nozzle 10 to 12 inches from the surface, at about 45-degree angle. Use extra caution when cleaning aluminum or steel siding. You can bend sections or blow them off the house. Windows can break if you spray directly at them. Make sure all windows are closed tightly. Don't spray under the laps of horizontal siding. And don't spray directly into crawl spaces or gable-end vents. When it's operating, never put your hand near the tip of the wand or aim it at a person or animal. Don't power wash on windy days. Keep at least 10 feet from any power lines. A telescoping wand, which you'll need to reach higher floors, can kick back up to 4 feet, each time you depress the handle. You'll be working with a lot of water pressure but with a little practice you should be able to control the wand.