Moss removal sprays and products
Moss killers, also called mossicides, are sold at hardware and garden stores. OSU Extension's guidance is that they work on contact but are short-acting: they wash off in rain, they do not give long-term control, and you still have to remove the dead moss. Follow the product label exactly, and keep runoff away from storm drains, streams, ponds and plants you care about.
Tools
- A soft or medium long-handled scrub brush, which OSU suggests when in doubt about pressure washing
- A leaf blower for loosened, dry moss
- Gloves and eye protection when handling products
- A tarp or plastic to protect plants below
What to avoid
- High-pressure washing. OSU notes that improper pressure washing can damage shingles.
- Scraping hard. It tears granules off asphalt shingles.
- Walking a wet roof. This is the most common way people get hurt.
When DIY makes sense
A single-story house, a low pitch, light moss and a dry day. Otherwise the cost of a professional is small compared with a fall or a damaged roof. HomeAdvisor lists a Salem average of about $420 for roof cleaning. See the cost guide.
Whatever you do, change the conditions
Moss comes back where it is shady and damp. Trim branches, clear debris, and see prevention.
Prefer to leave it to someone else? Get a free quote.