Does anyone have an opinion regarding zinc strip installation to deter moss?
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I have read pros and cons on installing zinc strips to deter moss and lichen. My House is surrounded with pine trees and I have a good amount growing on the north side of my house. Im hoping Martin will chime in with his opinion on this. Is it worth the expense? Will it do more harm than good? Thanks all
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Katherine,
I'm not sure about moss and lichen, but zinc, copper, and lead are all effective at deterring roof algae.
All you need to do is install a metal ridge cap. Galvanized steel is cheap and it works. (Galvanization is simply zinc coating.)
For more information on roof algae, see an article I wrote on the topic for the Journal of Light Construction: Algae on Asphalt Shingles.
Zinc strips rely on the zinc being carried by the rain to the affected areas, which doesn't always occur reliably or consistently. The most effective,benign and easy to apply treatment, which many shingle manufacturers recommend is Tide with Bleach. Sprinkle the granules on the roof during a period when they won't get rained on for at least three days. The moss will die. The remains of larger areas that have been allowed to grow for an extended period may need brushing off with a gloved hand.
How close are the pines? Best not to allow trees to grow large too close to the house - pollen, mold and root damage to the foundation are all common problems. Not to mention storm damage, leaf litter clogging gutters etc. etc. Best to keep a good protective clearing around the home. We all love trees but it's not very green to allow premature deterioration of our buildings, I think?
Thank you for your answers. I had heard bleach would kill the moss but I was reluctant to use liquid bleach. The tide powder with bleach sounds like a great, cheap solution that won't put any additional holes in the roof. It sounds more friendly to the environment and to me.
. The trees are about 20 feet away and they are on my neighbors property. I do love them too so they won't be going anywhere. I do curse them when I clean the gutters, which has to be done quite often! Thanks again!
Following is a link to a product that's supposed to work well ... for cleanup and prevention, and environmentally friendly to its surroundings.
http://wetandforget.com/product_wet_and_forget_outdoor.html
I had lichen and black stains but didn't like the looks of a zinc strip. So I bought powdered brass (ie, copper and zinc) and sprinkled some on the ridge. Worked well and is apparently still working 18 months later. My theory is that the powder gets down among the asphalt shingle granules and doesn't disappear with the first rain.
I can vouch for the Wet & Forget. It takes a few months to work, hence "Forget". We sprayed 1/4inch thick moss on shaded area of asphalt shingles, a few months later shingles looked like new. Two years later, moss has not returned.