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Steve G
How to remove moss on roof shingles

I have a North facing upper and lower roof.After I had the the trees trimed back I noticed a large area of green on both roof shingles.I have asked my local Home Depot if they had anything to remove this, and they looked at me like I had two heads.I tried spraying a 10% bleach solution on it but that didn't work.I was also affraid I would bleach out the color of the shingles.Any ideas?
Thnaks
Steve G

Debra
Re: How to remove moss on roof shingles

I found this
http://www.thisoldhouse.com/toh/asktoh/question/0,,401167,00.html

I know there was an ATOH segment where Tom installed some metal strips on the roof to act as an algicide I think it was zinc like the article recommends.

goldhiller
Re: How to remove moss on roof shingles

You could try dissolving some copper sulfate granules in water and spraying that on the stuff. Leave set for a few hours/half a day. Not sure you'd even have to rinse it off, but the runoff when it rains could very well damage the plants beneath.....so taking control of that by purposely rinsing might be the way to go.

Copper sulfate granules should be available at either a well-stocked greenhouse,ag supply store or ag fertilizer biz.

We use it to kill the algae that grows in galvanized livestock water tanks. Yes, the stuff will grow in there despite the zinc in the galvy coating. The CS whacks it dead in fairly short order. Turns brown and floats to the top in about a day or two. (That's at a concentration of a couple handfuls to 400 gallons of water. Higher concentration should kill much faster) Drain tank and refill with clean water for the livestock. No scrubbing and clean as a whistle.

If in doubt about potential for color shift to the shingles.....try a test first on a spare shingle. I think it'll be fine, but better safe than sorry.

I would think that salt/salt water..... would also do the deed. Would/could likely have some corrosive effects on metal gutters and such though.......and of course the runoff would also harm plants below. Controlled rinse and capture would be necessary.

Have seen moss-killer sprayable concentrates in a bottle at a greenhouse and at lawn/garden supply section of big-box. Don't know what's in it........didn't look.

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