Roof Zinc can protect your roof from roof fungus just like its name suggests. The theory is quite simple, attach a piece of zinc metal to the ridge of your roof and as it rains the water will pull metal ions from the zinc and the rain water will spread them down the roof. Metal ions has been used for treating mold, algae and fungus for over 100 hundred years. Pools, ponds, the boating industry and the gardeners have all used metal ions successfully to treat fungus.
Roof zinc like most metals comes plated or pure, plated zinc is much cheaper and will only be effective until the zinc washes off, where pure zinc will last the life of the roof, a much wiser choice.
Roof zinc comes in different widths, anywhere from 2 inches to 6 inches. The width of the zinc dictates the amount of protection you can expect from the metal ions runoff. There is a simple rule of thumb that states for every inch of zinc revealed one can expect 10 feet of down roof protection. 2 inches of zinc equals 20 feet of protection, 3 inches equals 30 and so forth. A roof on an average home has a run (ridge to gutter) of 24-30 feet.
Zinc Roof Defense is manufactured at .009 inches thick and 3.75 inches in width more than enough coverage for even the largest US homes. . To keep a roof clean, certainly the more zinc, the better the protection. This is not an area that you want to skimp on; we would not recommend applying any form of zinc below 3 inches wide unless you would be placing a second strip of zinc halfway down the roof.