Funny how most of these articles, are written by people that have never painted a house. This article suggests 1500 psi is starting low. If your painting Rinse your home down with a pressure nozzle attached to the garden hose. Their way will be removing stucco along with airborne dirt. If you think its necessary have at it, but common sense and a little look see around the base of your home, will likely show where stucco popped off from a sprinkler. In extreme cases it may be necessary , but most times it causes more harm than good. Gently rinse the house……Power washers are great for concrete cleaning, test a hidden spot with 1500-2000 psi and notice how it etched your concrete…..done sporadically this will leave lines all over the your $ and time And rinse your house down a day before you paint.