Why Should I Be Concerned About Moss on My Roof?

Brad GordonCleaning, Roof Maintenance


There are a lot of advantage to living in Vancouver and the Lower Mainland, but one of the things we do have to contend with is the constant rain and damp. Unfortunately, a constant companion in the temperate rainforest where we live is moss. Green roofs are totally in these days, but you should be concerned about of you see moss on your roof.

Some people like the rustic look of moss. While it may look romantic in a garden, a thick layer of moss can have some devastating effects on the health of your roof.

Moss grows perennially, meaning that it is a plant that lives beyond two years. You will find it on spots of your roof that are cool, damp, and deprived of steady, direct sunlight.

You’ll first notice moss growth appearing as a thin green layer overtop your shingles. You’ll probably see more of it between and underneath the edges of your shingles since that provides an even damper, shadier environment where it can flourish.

Moss Roof Damage

As the moss grows and thickens, moss will force the shingle apart and away from the roof, causing unprotected areas where water is able to seep. Loosened shingles can easily blow away during a storm, exposing even larger unprotected areas to the elements.

Once you have some thick, lush moss taking hold on your roof, it can act like a sponge, storing water. This will thoroughly saturate the roof underlay and eventually reach the sheathing below. Once this damp enters your attic and home, mold and further damage can occur.

Moss can drastically shorten the lifespan of a roof. When you spot moss growth, contact a roofing company for their opinion on how best to deal with the hazard. If left untreated, severe and expensive repairs may need to be undertaken. As you’ve heard a million times, an ounce of prevention is worth a pound of cure.