Roof Cleaning
Kill Moss at the Root, Without Damaging the Shingles.
Standard pressure washing strips the protective granules off asphalt shingles. We use low-pressure treatment methods instead.
Overview
What Is Roof Cleaning & Moss Removal?
Roof cleaning removes moss, algae, and organic debris from the roof surface using low-pressure treatment methods rather than a pressure washer. It's for a roof that's structurally sound but has visible growth or buildup, restoring the surface without stripping the protective granules off asphalt shingles.
Why Clean
Moss holds moisture and can lift shingle edges over time.
What We Remove
Moss, algae streaking, and general organic buildup.
When Cleaning Isn't Enough
If damage has already reached the decking, that's a repair.
Signs To Watch For
Why Does Moss Grow On Washington Roofs?
Moss needs shade and consistent moisture to establish itself, and Western Washington roofs get plenty of both. North-facing slopes, roofs under heavy tree cover, and areas that stay damp between rain events are the most common places it takes hold, especially on asphalt shingles, which give it a rougher surface to grip than metal or tile.
Visible moss on shingles or in valleys
Black algae streaking
Roofs that have never been treated or cleaned
What You Get
Why work with JBA on this.
No high-pressure washing
High-pressure equipment strips granules and can void manufacturer warranties. We don't use it on asphalt shingle roofs.
Root-level treatment
Treatment targets moss at the root, not just the visible surface growth.
Process
How it works
- 01
Assess
Check the extent of moss or algae growth and any shingle lifting it's caused.
- 02
Treat
Apply low-pressure treatment to kill growth at the root.
- 03
Clear
Remove debris and treated growth from the roof surface and gutters.
What We Address
What Does Professional Roof Cleaning Address?
A few things account for most of what a cleaning visit needs to handle.
Moss buildup
The most common issue on shaded or tree-covered roofs, especially on north-facing slopes.
Organic growth
Algae streaking and other growth that develops on the roof surface over time.
Loose debris
Leaves, needles, and small branches that collect in valleys and along edges.
Valleys
Where debris and moisture concentrate most, and where buildup is often worst.
Roof surface condition
General dirt and grime that accumulate gradually and hold moisture against the surface.
Drainage visibility
Making sure water has a clear path off the roof instead of pooling behind buildup.
Before The Rain
Why Check Your Roof Before The Rainy Season?
Moss and debris that build up over the dry months hold even more water once the rain starts, which is exactly when a small amount of buildup turns into a bigger problem. Clearing it beforehand gives the roof a clean start heading into wet weather.
Compare Your Options
What's The Difference Between Cleaning And Repair?
Cleaning removes moss, algae, and buildup from a roof that's otherwise structurally sound. Repair fixes actual damage, like a compromised shingle, deck, or flashing. If growth has already caused damage underneath it, that's a repair conversation, not just a cleaning.
The Risk
Can Moss Damage A Roof?
Yes, over time. Moss doesn't just sit on top of shingles. As it grows, it can lift shingle edges and work its way underneath them, which gives water a path it wouldn't otherwise have. Left long enough, that moisture held against the roof deck can lead to the kind of decking damage that turns a cleaning job into a repair.
Visible moss, black streaking, or a roof that hasn't been cleaned in several years are the usual signs it's time to look at cleaning. Heavier tree cover generally means more frequent attention.
A Common Question
Why Shouldn't I Just Pressure Wash My Roof?
High-pressure cleaning can strip the protective granules off asphalt shingles and damage the surface underneath, which is why we don't use it. Cleaning methods should match the roofing material and the manufacturer's guidance, not whatever equipment happens to be on the truck.
We use low-pressure treatment methods on asphalt shingle roofs instead, which kill moss and organic growth without stripping the surface.
Know The Limits
When Cleaning Isn't Enough
If moss has already caused shingle damage or water has reached the decking, cleaning alone won't fix that. At that point, a repair (or in some cases replacement) addresses the underlying damage, with cleaning as part of getting the roof back to a maintainable condition.
Between cleanings, keeping gutters clear and trimming back overhanging branches where practical both help slow how quickly moss and debris build back up.
If you’re comparing quotes and one of them mentions a pressure washer for your asphalt shingle roof, ask about it directly. It’s one of the more common ways a roof cleaning job accidentally shortens the life of the roof it was meant to help.
Real JBA Work
See This Service In Action.
See more of our completed roofing projects on the Our Work page.
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Reviews
What customers say about roof cleaning & moss removal.
Excellent quality work! Crew came on time and without wasting anytime they started working. Cleaned up my gutter, roof put moss treatment, cleaned up backyard deck, driveway, porch. Crew was focused and attention to details. Highly recommend them 10/10!
I am very impressed by awesome work Jhony's team has done! Our gutter and roof look like new ones after the cleaning. Highly recommended to everyone who needs gutter and roof cleaning!
Homeowner Questions
Roof Cleaning Questions
Does roof cleaning guarantee my roof won't need repairs?
How often should I have my gutters cleaned in the Pacific Northwest?
Can moss damage shingles?
How often should a roof be cleaned?
Is roof cleaning safe for asphalt shingles?
How is roof maintenance different from roof cleaning?
Will pressure washing damage my roof or void the warranty?
Why does moss grow on my roof?
Service Areas
Serving King, Snohomish & Skagit Counties
Ready To Talk About Your Roof?
Free estimates for homeowners across King County, Snohomish County, and Skagit County.
24-Hour Service · Financing Available