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Kleen Roof and Exterior Cleaning wrote:

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I have seen 4-5 roofs that look like this this summer.  I don't think it is some kind of infestation, I think it is some type of roof treatment.  They have all been in higher end neighborhoods.

I noticed them while cleaning roofs in the same area. The houses are all the same age, and most have black streaks, moss and lichen. These roofs have nothing. Except the white substance on them. I have checked back on the houses during the summer, and most of them are loosing the white "stuff"

 

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 Hard to say w/o being there to see it.  It does not look good on the shingles

This is an update to what is on the roof. I have seen a couple of them this year. I stopped and asked one of the home owners what was up with the roof.
What it is is Tide laundry soap. They go up on the roof and sprinkle it all over. They were told it will remove the black streaks, moss and lichen. They found it on the internet, so it has to be true.