Family-owned since 1997Licensed & insured in WashingtonTacoma office · 3818 S 66th St
Family-owned since 1997 · 10% off for veterans & military
Family-owned since 1997Licensed & insured in WashingtonTacoma office · 3818 S 66th St
Family-owned since 1997 · 10% off for veterans & military
Tacoma, Washington · Roof care
Moss holds water against your shingles, lifts their edges and sheds grit into the gutters. All Season Continuous Gutters & Roof Care clears it from shingles and roof valleys, treats the roof to slow regrowth, then flushes the gutters and downspouts below. One visit, from our South Tacoma office.
Estimates within 24 hours, from your photos or on site · Family‑owned since 1997
One visit, three jobs
What a Tacoma moss visit covers
Roof moss removal in Tacoma
Roof moss removal in Tacoma means clearing moss from the shingles and roof valleys, treating the roof to slow regrowth, and flushing the gutters and downspouts the moss was feeding. Order matters. Moss sheds grit as it comes off, so the roof goes first and the gutters after, or you pay for a cleaning the roof refills.
The thickest growth is usually in the valleys and on the lower courses of shaded planes, where water, needles and cedar sprays collect and stay wet.
A treatment goes on once the moss is off. It slows new growth. It can’t stop new spores from landing, which is why shaded roofs need a regular check.
Moss and loose granules wash straight into the gutter. We flush the gutters and downspouts below the roof so that grit doesn’t settle into a sludge that blocks the outlet.
Both photos are real before‑and‑after shots from our Washington moss jobs.
Tacoma conditions
Moss needs steady moisture and shade, and Tacoma supplies both. NOAA’s 1991–2020 normals put Tacoma’s rain at 40.81 inches a year, about 76% of it from October through March, on roughly 155 wet days. Under Douglas firs and western red cedars, a north‑facing roof plane can stay damp for most of that season.
40.81″ Average rain a year in Tacoma
76% Falls October through March
~155 Days a year with measurable rain
Monthly rain in inches. Teal marks the October–March moss season; November is the wettest month.
Tall evergreens block the low winter sun and keep dripping after the rain stops. Fir needles and cedar sprays settle on the roof and hold water.
They get the least direct sun and dry last, so moss usually starts there and comes back there first.
Needles and big‑leaf maple leaves pile up where roof planes meet. That damp mat gives moss a place to start.
Photo: JamesDeMers via Pixabay.
Cleaning methods
No. The Asphalt Roofing Manufacturers Association says never to pressure wash an asphalt shingle roof, because it causes granule loss and very likely premature failure. OSU Extension gives the same advice for moss: remove it with a brush or broom, skip high‑pressure devices, then apply a product to slow regrowth.
High‑pressure washing
Gentle removal and treatment
Roof type matters. Cedar shakes, tile and metal each need their own approach. Tell us what’s on your roof when you book, and ask how it will be cleaned. Any roof cleaner should be able to explain that in plain words.
Sources: ARMA, Algae & Moss Prevention and Cleaning · OSU Extension, How to remove moss from my roof
Signs to watch for
Moss rarely shows up all at once. It starts as green along the shingle edges on the shady side and works its way down to the gutters. Here’s what to look for from the yard, and the fix for each.
What it meansMoss is rooting where shingles overlap and water lingers longest.
The fixClear and treat it now, before the edges start to lift.
What it meansMoss is growing under the leading edge. ARMA warns that raises the risk of shingles blowing off in wind.
The fixClear the moss, then have a roofer check any shingle that won’t lie flat.
What it meansMoss and loose granules are washing off the roof with every rain.
The fixClear the roof first, then flush the gutters and downspouts.
What it meansThe roof above is still shedding moss and needles into them.
The fixBook moss removal with gutter cleaning, or ask about gutter guards.
What it meansUsually algae, not moss. ARMA says there’s no scientific evidence algae damages shingles, though it stains them.
The fixMostly a looks issue. Mention it when you book so it’s part of the same visit.
Timing
For most Tacoma roofs, spring is the window. Rain eases from 4.38 inches in March to 2.00 in May, and the dry months are ahead. Clear the roof before your fall gutter cleaning too, so the moss it sheds doesn’t refill clean gutters the first time November’s rain arrives.
SpringMarch – May
Best window
Rain tapers off. Clear and treat the roof, then flush the gutters before summer.
SummerJune – September
The driest stretch: July averages 0.55 inches. A good time to wash the moss off patios and walkways below.
FallOctober – November
Rain returns and big‑leaf maples drop. If the roof still has moss, do the roof first and the gutters after.
WinterDecember – February
Moss grows on wet, shaded planes. Watch for green along the shingle edges and book the spring visit early.
How long it lasts
A treatment slows regrowth, but it doesn’t change the conditions moss likes. An open, sunny roof stays clear much longer than a north‑facing plane under firs, which is where moss comes back first. OSU Extension notes moss products may only work for a short time and need reapplication.
“You can clean all you want but to keep moss at bay, the environment needs to change. You’ve got to let the sun in or it will return.”Jay Pscheidt, OSU Extension plant pathologist
Make it last longer
Cost
We don’t publish a flat price, because two Tacoma roofs of the same size can take very different work. Roof size and pitch, story height, how thick the moss is, the roofing material and the gutters to flush below all change the number. The instant estimator prices your roof from your address and a few answers.
More planes, valleys and dormers mean more edges and corners to clear.
A steep two‑story roof takes more setup and safety gear than a low ranch.
A light film comes off faster than thick cushions packed into every course.
Composition shingles, cedar shakes and tile are each cleaned differently.
Flushing out the grit is part of the job, so the gutter footage counts.
Overhanging firs, tight side yards and planting beds below add time.
Price it now
See a price range for your roof in about two minutes
Enter your address and answer a few questions. No sales visit needed to get a first number.
Schedule online or call (425) 828-3000
Estimates aren’t quotes. The range is preliminary and non‑binding. Our local team reviews every request before any price is final. Need the gutters cleaned too? Ask about bundle pricing on your estimate.
Licensed & insured in Washington
Check us on L&I Verify a Contractor
Estimates within 24 hours
From your photos or an on‑site visit
Family‑owned since 1997
Run from our South Tacoma office
Runoff & Puget Sound
Everything that comes off a roof lands in the gutters, then the yard or the storm system. Washington’s Department of Ecology estimated moss control is the biggest potential source of zinc in a study area it used to stand in for Puget Sound cities, and zinc is toxic to fish. What happens below the roof matters as much as the roof itself.
Sources: WA Department of Ecology, copper and zinc in runoff · OSU Extension, controlling roof moss
Honest limits
It isn’t roof repair.
We don’t replace shingles, flashing or underlayment. If clearing the moss shows damaged or missing shingles, we point it out so you can have a roofer look at it.
It won’t stop a roof leak.
Water inside the house or stains on the ceiling need a roofer, not a cleaning.
It can’t put granules back.
Shingles that are already bald, brittle or curled stay that way once the moss is gone.
It won’t keep moss away for good.
Shade and rain bring it back. Treatment slows it; sun and regular upkeep do the rest.
It won’t fix leaking or sagging gutters.
That’s gutter repair in Tacoma, and you can ask for both on one estimate.
Zinc strips aren’t a quick add‑on.
ARMA doesn’t recommend adding them to an existing roof, because it takes exposed nails or breaking the shingle seal.
Where we work
Our Washington office is in South Tacoma, so most of the city is a short drive. Moss looks different by neighborhood: big street trees over older North End roofs, firs above the West End, long low ranch roofs in the South End.
Tacoma office
All Season Continuous Gutters & Roof Care
3818 S 66th St, Tacoma, WA 98409
(425) 828-3000Seattle homeowners: see roof moss removal on our services page. Everything else is on the Tacoma gutter company page.
North End & Proctor
Older roofs under big street trees
Stadium & North Slope
Tall historic homes, steep pitches
West End & Point Defiance
Douglas firs shading the roof all year
Old Town & Ruston
Hillside roofs above Commencement Bay
Central & Hilltop
Century‑old homes on tight lots
South Tacoma & South End
Our home base, mid‑century ranches
Also near Tacoma
Often booked with moss removal
Questions & answers
What Tacoma homeowners ask before they book a moss visit. Still unsure? Send us a photo of the roof.
It depends on roof size and pitch, story height, how heavy the moss is, the roofing material and the gutters to flush below. We don’t publish a flat price. The instant estimator gives a preliminary range for your roof, and our local team confirms it before anything is final.
Not an asphalt shingle roof. The Asphalt Roofing Manufacturers Association says pressure washing causes granule loss and very likely premature failure. OSU Extension recommends a brush or broom and no high-pressure devices. Save the pressure washer for concrete.
Spring is the usual window, as the rain eases and the dry months start. Clear the roof before your fall gutter cleaning, too, so the moss it sheds doesn’t refill clean gutters.
It depends on shade more than anything. A treatment slows regrowth, but OSU Extension notes moss products may need reapplication, and shaded north-facing planes under firs come back first. Trimming branches so sun reaches the roof makes the results last longer.
It can. Moss holds water against the shingles and can lift their leading edges, which ARMA says raises the risk of shingles blowing off in wind. In severe cases, moss build-up can push water sideways under the shingles and damage the roof deck or cause leaks.
Moss sheds grit and granules as it comes off the roof, and it all lands in the gutters. Flushing the gutters and downspouts after the roof keeps that sludge from blocking the outlets in the next storm, so you don’t pay for a cleaning the roof refills.
They can be. Washington’s Department of Ecology says zinc is toxic to fish and estimated moss control as the biggest potential zinc source in its Puget Sound–area study. Ask what goes on your roof, and mention copper gutters or flashing, since zinc corrodes copper.
No. Roof moss removal is cleaning, not roof repair. If we see damaged or missing shingles while clearing the moss, we point them out so you can have a roofer take a look. We do repair gutters and downspouts.
Every request goes to our South Tacoma office, and estimates are free.
All Season Continuous Gutters & Roof Care · 3818 S 66th St, Tacoma, WA 98409 · (425) 828‑3000 · Family‑owned since 1997