Seattle’s wet, mild climate is great for evergreens and terrible for roofs and gutters. Fir needles, maple leaves and roof moss pile up every fall, and once the rain starts in earnest, clogged gutters overflow and moss soaks up water against your shingles. Here is a simple calendar and what each job involves.
Why moss and gutters matter here
Moss lifts the edges of shingles and holds moisture, which shortens the life of a roof. Clogged gutters send water over the edge, where it can rot fascia boards, stain siding and pool near your foundation. Shade from big trees and north-facing roof slopes make both problems worse, which is why so many Puget Sound homes deal with them every year.
A simple yearly calendar
- Late summer to early fall: roof moss removal and treatment, while the roof is dry enough to work on and before the wettest months.
- October to November: gutter cleaning after most leaves have fallen. This is the busiest time of year, so book early.
- Late winter or spring: a second gutter cleaning for homes under fir or maple trees, plus a check of downspouts after winter storms.
- Late spring to summer: pressure washing driveways, patios and decks, and window cleaning after pollen season.
What a good gutter cleaning includes
Debris removed by hand and bagged, downspouts flushed and tested, light debris cleared from roof valleys, and a quick inspection for loose brackets or leaks. Confirm the price includes downspouts, not just the troughs.
Published prices from listed companies start around $200 for a one-story home and $250 for two stories. See our gutter cleaning page for companies and current prices.
Moss removal: what to ask
- Method: hand brushing or soft washing is gentler on shingles than high-pressure washing, which can damage asphalt roofs.
- Treatment: ask what product they apply afterward and how long it keeps moss from returning.
- Gutters: moss removal fills gutters, so the job should finish with a gutter cleanout.
- Insurance: roof work is risky; confirm the company carries liability coverage.
One listed company publishes moss removal from $500 for a one-story home and moss treatment from $100. Compare more on our roof moss removal page.
Things you can do yourself
- Trim branches that overhang the roof to let in light and reduce debris.
- Check downspouts from the ground during heavy rain; water spilling over the edge usually means a clog.
- Keep an eye on north-facing slopes, where moss shows up first.
- Leave ladder and roof work to insured professionals, especially on two-story homes and steep roofs.
Bundle to save
Many exterior companies do gutters, moss, window cleaning and pressure washing. Booking several jobs in one visit often costs less than separate trips.
Need a cleaning company?
Compare Seattle gutter cleaning and moss removal companies, or request free quotes from up to 3 of them.
Frequently asked questions
When should I clean my gutters in Seattle?
At least once a year in October or November, after the leaves fall. Homes under fir or maple trees often need a second cleaning in late winter or spring.
When is the best time for roof moss removal in Seattle?
Late summer through early fall, when the roof is dry and before the wettest months, so treatments have time to work.
Is pressure washing safe for my roof?
High pressure can damage asphalt shingles. Most roof cleaners use hand removal or low-pressure soft washing.