How Moss Damages Roofs
- Loosen shingles. As moss underneath shingles grows thicker, it lifts the shingles and causes them to become loose.
- Strip protective oils. Asphalt shingles have oils that hold the top layer of granules in place. Moss strips these oils, which causes the granules to erode.
- Cause wood rot. Moss absorbs and retains water, causing the wet moss underneath the shingles to rest on the roof’s wood frame.
- Add additional weight. The water that moss retains when it rains can add a lot of additional weight to your roof and will eventually need reinforcing or repairing.
- Block gutters. Like other debris, moss can grow thick enough to clog your gutters, preventing them from carrying water off your roof as they should.
