| Roof type | How moss behaves | Handle with care |
|---|---|---|
| Asphalt / composition shingle | Clings to the surface and shingle edges and can lift shingles | Avoid high pressure, which can strip granules |
| Cedar shake or shingle | Holds moisture and can degrade the wood | Gentle brushing and low-pressure methods |
| Metal | Rarely takes root; metal is slippery for moss | Slick when wet, so safety first |
| Tile or concrete | Collects in textured surfaces and between tiles | Tiles can crack if walked on carelessly |
If you are replacing the roof
OSU Extension notes that a metal roof is a way to avoid moss, as it does not take root easily. Algae-resistant shingles with copper granules are another commonly recommended choice in damp climates.
Not sure what you have?
Just say so in the quote form. A local company can identify it when they look at the roof.