I'm sure AC can give you some good info on it. I was a little worried when i read about algae resistant shingles also. if you go on the manufactures web sight you can read all the info. the difference is they have copper granulars spread out through the shingle. So when you get a morning dew that dew will possess enough mineral to keep the shingles clean. They say this shingle is garrenteed to keep shingles free from black algae for about 10 years i think. it also said that any moss and lichen would void the 10 year warrente. If you got bleach on them i dont think it would cause a problem but i would call the manufacture to double check. they also cost a lot more then normal shingles so most people don't pay for them. maybe we are talking about a different shingle. let me know

safe roof cleaning hartford wrote:

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I'm sure AC can give you some good info on it. I was a little worried when i read about algae resistant shingles also. if you go on the manufactures web sight you can read all the info. the difference is they have copper granulars spread out through the shingle. So when you get a morning dew that dew will possess enough mineral to keep the shingles clean. They say this shingle is garrenteed to keep shingles free from black algae for about 10 years i think. it also said that any moss and lichen would void the 10 year warrente. If you got bleach on them i dont think it would cause a problem but i would call the manufacture to double check. they also cost a lot more then normal shingles so most people don't pay for them. maybe we are talking about a different shingle. let me know

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 It all sounds good in theory from the manufacturers, but once the copper content in the shingles patinas/oxidizes it is rendered useless. Yes you probably get a roof that last just a little longer without algae, but it will grow.

 

Chris