The first step in paint surface preparation is to remove the loose paint. One method used to do this and clean the house at the same time is called "power washing." Some people love these tools and some don't. A power washer uses water from your hose and increases the water pressure as it leaves the wand to between 2,200 to 3,500 psi. In the hands of an experienced painting professional this tool can be useful. However in the hands of the inexperienced it can damage your home:
- At high pressures the water jet can etch wood, even brick and blast mortar from joints.
- Power washer will remove loose paint but may also lift or weaken the bond of good paint surrounding the removed loose paint.
Other issues with power washing include:
- The high pressure water can soak the wall and requires time to dry out before painting.
- Since the power washer does not fully remove all loose paint, the wall still needs hand scraping after the power washing and drying period.
- In the end, power washing is no substitute for hand scraping.
I don't mean to sound down on this tool because I'm not, I use them for a lot of cleaning chores. I've just seen them improperly used in paint removal and an entire house started to peel a few months after it was power washed and painted because of aggressive power wash pressure and painting too soon.
My preferred use of this tool for painting is at a lower pressure just to wash the dirt from the wall, not at high pressure to blast paint from the wall.
Power Washers:
