Is It Bad If Moss Grows On Your Roof?

Moss grows on rooftops in some climates. This is especially true in moist, shady parts of the country. If you live in an area where moss is prone to growing on rooftops, then it's important to know why moss grows on the roof, what it can do to your roof, and how you can stop it.

Is it bad if moss grows on your roof?

Moss that grows on a roof will hold moisture against the roofing material. During freeze/thaw cycles, this can cause the quick deterioration of the roofing material and the sheathing underneath. This cycle is especially problematic on wood shingle roofs, because it causes wood to crack and rot very quickly. If moss is allowed to continue to grow on the roof, it may eventually damage the roof so badly that it necessitates roof repair.

What's the difference between roof moss and roof algae?

Roof moss is thick, fuzzy, and plant-like and can easily absorb and trap moisture against the roof shingles. Algae is thin and doesn't hold moisture against the surface of the roof. Roof algae is more of a cosmetic problem than a maintenance issue.

What causes moss to grow on a roof?

Moss is especially prone to growing in areas that lack direct sunlight and in areas where the temperatures are generally cool and mild. Moss is commonly found in wooded areas with a lot of trees and plant life already growing.

How can you remove moss from a roof once the moss is growing on it?

Moss can cause roofing materials to deteriorate, which means that any homeowner trying to remove moss from the roof should do so carefully. Power washers can wash away deteriorated shingles, doing more damage than good. Harsh chemicals can also help speed the deterioration process. The best way to remove moss that's growing on the roof is to use a rake or a soft brush to gently push the moss off the roof. If possible, you should sweep off the moss from a ladder, instead of doing so while standing on the roof. This is the best way to remove the moss and protect the roofing material.

How can you prevent moss from growing back?

If you would like to prevent moss from growing on the roof in the future, remove branches of trees nearby that put the roof in shade. Moss occurs naturally in some environments and will be difficult to completely eliminate, but making the environment more unpleasant for moss will help stop it from growing back.

For more information about how you can protect your roof from moss, speak with a roofing contractor from a company like A-1 Roofing & Siding.