Customers often call in and ask us “Do Zinc strips work to prevent roof moss? Or “Are Zinc strips effective at controlling moss growth?”
We’ll answer two questions in this article. First, we’ll look at whether Zinc strips actually do work, and second, we’ll look at how they compare to other methods of controlling or inhibiting roof moss.
Zinc strips can be somewhat effective at controlling moss growth. Zinc strips work by slowly releasing zinc particles when rain water hits the strips. That rain water then runs off and inhibits moss and other organic growth on your roof.
However, studies have shown that zinc strips are only mildly effective and that their effectiveness wears off relatively shortly. Different studies show zinc strips being effective for 5-15 feet below the zinc strip, meaning many roofs would require multiple layers for effective control. For the average homeowner, the negative appearance of multiple layers of zinc strips make them a non starter for moss control.
Further, studies have also shown that zinc strips lose their effectiveness after just 5 years. This means zinc strips are not a permanent solution to roof moss, and need to maintained themselves.
Yes. Installing zinc strips to prevent moss growth is a leak liability, says the Asphalt Roofing Manufacturers Association. In order to install zinc strips, you must either nail them in over the asphalt shingles or break the seal and install them under a strip of shingles. Both methods of installation open the roof up to potential leaks, and therefore are not recommended.
Yes, there are different methods of moss control, which we covered more extensively here. They consist of choosing metal roof types, pruning nearby trees, and regular (every 4-6 years) chemical treatments.
The most cost-effective, safe, and aesthetically pleasing method for moss control is a combination of tree pruning and roof cleaning treatments.
Pruning should be done regularly to prevent any trees from overhanging your roof. West Coast Moss Removal can help you with your pruning at the time of your roof cleaning, and make suggestions for how far back you should prune in the future. As a rule of thumb, it’s best to keep six feet distance between trees and your roofline.
Finally, periodic roof treatment will keep your roof in like-new condition. The average homeowner will only need to apply these treatments every 4-6 years.
To learn more about how we approach roof cleaning and maintenance, click here.