Just wanted to share some pics of how zinc strips do not work! Occassionally people will ask me if zinc strips are an option. All I have to do is show them these pictures. This roof is only 8 years old and has had zinc strips since day one. How are the zinc strips performing? NOT GOOD!
Its 12/12 and we are still cleaning in Cincinnati!
I see this all the time, the only way they work is if they are installed every few feet or so in rows traveling across the roof. Copper works a little better, but nothing is guaranteed to work. Nice photos!
Am i seeing the third picture right....the zinc looks to have worked for the first foot or so and then its infested? maybe its just the shadows. would you mind if i borrowed these to educate my customers in Iowa about the failure of zinc strips?
My take is that they did work a little, but working a little is not what people expect. My guess is they "might" have created a greater concentration of algae in the lower area of the roof, maybe the same effect of spaying a ridge cap only. I know this topic has been presented in prior post, but I thought it was worth a rehash. I have never seen them installed every two inches. How much would that cost?