Power Washing

QUESTION: When I had my aluminum-sided house power-washed, it came out streaky. Do I have to paint it, or will power-washing it again get rid of the streak? If I paint, how?

ANSWER: Those streaks are probably indelible. If the power-washer started from the top down, he washed over a dry, dirty surface. That is why washing should be done from the bottom up, so that water will run down a wet surface, preventing the streaks. If you decide to paint this the way to go: Sand the finish heavily enough to roughen it and reduce gloss, if any. Wash with a strong detergent solution and rinse. Apply two think coats of solid color latex stain or latex house paint. You might be able to find a latex paint specifically for aluminum siding.

*****

QUESTION
Should vinyl siding be power washed?

ANSWER
No. The strong stream from power washing is likely to get behind
the vinyl, causing decay and other odious things. The same goes for
aluminum siding. Another reason for the taboo is the direction of that
powerful flow: usually upward (and under the vinyl). How to get a power
washer to aim downward is a good question. One reader, however, said he
safely pressure washed siding by reducing the pressure of the power washer.
And, he said, aiming the power stream correctly helps keep water from
getting under the siding.

********************************************

Question
Is there any cleaner to use when power washing a house? And what kind of power washer do I need to do form concrete?

Answer
For power washing the house, use your favorite cleaner. As for power washing the concrete, try one with maximum power if the concrete is spalling or loose. My favorite is spic and span, the liquid. One caveat: Do not power wash aluminum or vinyl siding. If the high power is used, and the stream of water is aimed upward, water can get behind the siding and will never dry out. A power washer in New Orleans called some time ago to tell me that if you reduce the power of the water, and force the flow downward, there will be no problem with water getting behind the siding. Not all power washers can or will do that, but if you can find one who does, you're home free.

Return to the "Crusader Q&A Topics" page!

---