Do Not Use a Power Washing Machine to Wash a Shingle Roof

We had to get our roof cleaned because it had black stains and moss all over it. We called a power washing guy to see what he could do. Now we did not look into cleaning roofs or what methods were recommended we just went with what this power washing guy said. He said he could get up there and power wash the roof and get rid of the streaks.

He took his power washing sprayer up on the roof and started to wash the shingles. At first it didn’t look like anything was happening. The black stains were pretty stubborn but he said he could turn up the pressure on his power washing unit. I thought man, isn’t that going to hurt the shingles, but he said it was okay.

Well I did some searching on the Internet has he was power washing the roof. I found that the major shingle manufacturers warn against the use of a power washer on the roof. It says it can lessen the longevity of the roof by blasting off the shingle granules. I almost came out of my chair.

I continued to read that they recommend a low pressure chemical application that will both kill and remove the black roof stains. I ran outside and yelled up to the power washing guy. I showed him the information and he did not know what to say. I ran him off and later found a professional power washing company that used the low pressure roof cleaning methods. Now our roof is completey restored. I hope the power washing didn’t do too much damage.