Vinyl siding can safely be washed with a pressure washer, provided the washer's manufacturer recommends doing so, according to Bob Vila. When washing this type of siding with a pressure washer, it is important to point the washer's nozzle straight instead of at an angle and to keep the stream at eye level. This keeps the water from being driven behind the siding.
Some pressure washer manufacturers advise against using their pressure washers on vinyl siding. Others recommend using the pressure washer, but limiting the amount of pressure used during washing. Homeowners should defer to the owner's manual when deciding whether or not to use a pressure washer on their home's vinyl siding, notes Bob Vila.