I purchased my currently home about a year ago. Recently I have noticed black stains, algae, and Moss on certain parts of the roof. These were not present when I purchased the home. I assume the prior owner had these problems cleaned up.
I have read you can apply Zinc or Copper strips to the roof to prevent the black stains and Moss from coming back once they are removed with a non-chlorine based solution.
My question is what is the best way to attach these strips to the roof. Most articles talk about nailing the stripes to the roof. I am hesitant about nailing the strip. Any other ideas?
The zinc strips are intended to be installed below the ridge cap shingles, exposed to any water flow. Cost is less than $1 per linear foot, and should protect up to five years. Trace amounts of zinc are oxidized from the strip and run down the roof and are toxic to algae. Generally focus on north facing slopes and any roof areas where trees may overhang.
Don’t use copper as you will have green staining. Install using a nail with a neoprene rubber washer. These are often used in metal roofing, and will seal out any water from the penetration. Roofing cement could be used on the back-side, as you roll out the strip, but that is pretty messy. If you use it, I would confine it to just a dab at the attachment points.