Depending on how dirty the wood siding is, you might decide to have wood siding professionally cleaned. Typically, a professional cleaning company will offer to either pressure wash or steam clean wood siding. Pressure washing wood siding can remove paint, so you most likely will be repainting once the job is done. Choose the right professional company, as too much pressure can damage the wood siding.
You can also clean wood siding on your own. The best bet is to rent a power washer from a local home improvement store. Shut off the power to all outdoor lights that might get wet and cover landscaping plants and shrubs so cleaning solution does not drip on them. Start at the top of the house and work down when power washing wood siding. Rinse cleaning solution off the siding before it dries.
When you clean vinyl siding yourself, use a soft cloth or a soft bristled brush. If the siding is textured, use a soft bristled brush so stains are not worked into the texture. For vinyl siding, begin washing at the bottom of the siding and work your way up. This prevents streaking from soap and water running down the siding. Rinse all cleaning solution off the siding before it dries.
It also is possible to clean vinyl siding with a power washer. You can rent a power washer at a home improvement store, but it's important to read the instructions carefully before using it. Hold the power washer straight ahead at eye level. If you point the power washer upward, water may collect behind the vinyl siding, which could cause streaking or decay.