Before you repaint your house, you need to remove all loose and peeling paint. A pressure washer makes the job go faster, and you can do it yourself. Use a minimum 15 degree spray nozzle with even strokes 18 to 24 inches from the surface to avoid damaging the wood. For especially difficult areas, you can use a zero-degree nozzle, but to get the hang of it, practice first on an out-of-the-way place. Allow you siding to dry at least 24 hours before painting.