How To Protect Asphalt Roofs From Mold Growth

Moss, mold, algae, and mildew are all things that can begin to grow on the exterior of your home after an extended period of water exposure, and if left untreated, can cause damage to your home's roof. If the roof of your home becomes damaged, water can leak inside, allowing the growth of moss and mold to spread into the interior of your home, which can be a serious health hazard. Thankfully, there are a few fairly simple things that you can do to protect your asphalt shingled roof from mold and mildew growth.

Clean Gutters and Roof

A buildup of organic debris, like leaves and sticks, in your gutter system and roof can help trap water on your roof, and create the ideal environment for mold and moss to grow in. You should regularly clean out your gutter system to ensure the proper drainage of water and use a leaf blower or a similar method to remove any debris that may be stuck somewhere on the slope of your roof. Avoid using abrasive methods of cleaning, like scrubbing with a brush, as this can deteriorate your shingles at a greater rate and make leaks in your roof more likely.

Trim Surrounding Trees

Trim back any surrounding trees and plants that overhang your roof. On one hand, this reduces the amount of organic debris that builds up on your roof over time, reducing the amount of water that becomes trapped on your roof. On the other hand, it also increases the amount of sun that reaches your roof, which will in turn cause any water that does become trapped on your roof to evaporate faster, before mold can begin to grow.

Zinc Strips

If you live in an area with a climate of heavy rain, you may want to install zinc strips on your roof. These are thin metal strips that are hammered into your shingles just below the peak of your roof. Zinc is naturally inhibitive to plant growth, and as rainwater passes over the strip, it will carry a small amount of zinc with it down the shingles below the strip. This prevents moss and other plants from beginning to grow on your roof.

Bleach Treatment

If moss or mold does begin to grow on your roof, you can use a bleach treatment to remove it. Mix one part chlorine bleach with four parts warm water, and apply it to the affected area. Allow it to sit for five minutes, and then rinse it away with a garden hose. The bleach will kill any existing mold, and the residue will be enough to prevent further growth in the short term. Just be sure not to let the bleach sit for longer than five minutes, as it can begin to degrade your shingles.