Best Exterior Cleaning
Roof Cleaning and Moss Removal King & Snohomish County
Local roof cleaning that protects your shingles and treats constant moss. Same day estimates available. Serving King County and Snohomish County, WA.
Best Exterior Cleaning
Roof Cleaning and Moss Removal in King County and Snohomish County
If you own a home on the Eastside or in south Snohomish County, your roof is dealing with the same thing every other roof out here deals with. Heavy rainfall from October through March, thick tree canopy from Douglas fir and western red cedar, and moisture that sticks around well into spring. That kind of environment is a perfect setup for moss, algae, and lichen on just about any roof material. We see it on homes near green belts, under heavy tree cover, and in older neighborhoods where the canopy has had decades to fill in. Moss doesn't just sit on the surface. It sends roots into your shingle material and holds moisture against the roof deck, which is where the real damage starts. We're based in Redmond and we've been cleaning roofs across King County and Snohomish County for years. We know what grows out here and how to deal with it properly.
Best Exterior Cleaning
Signs Your Roof Needs Professional Cleaning
If you've noticed dark streaks running down your roof, thick green patches spreading near the ridge cap, or moss growing along the drip edge and around the flashing, your roof is past due for attention. Another thing a lot of homeowners miss is dark granules collecting in the gutters or at the bottom of the downspouts. That's granule loss from your shingle surface, and it means the protective layer is wearing thin. You might also see shingle tabs starting to lift or curl at the edges, especially on the north-facing side of the house where shade keeps things damp longer. In our experience, the most common mistake is waiting until the moss is thick enough to spot from the street. By that point, the root system has already worked its way into the shingle material and the underlayment, and the damage underneath gets more expensive to deal with. If any of that sounds familiar, it's worth getting a professional look before things move further.
Best Exterior Cleaning
What Our Roof Cleaning Service Includes
Every job starts with a full inspection. We check moss coverage, debris depth, shingle condition, the pitch, and how the flashing and ridge cap are holding up. From there we clear the roof by hand, brushing off moss and applying low-pressure air tools to blow out leaves, fir needles, cedar bark, and anything else that's piled up. We don't use pressure washers on roofs. High-pressure water strips the granule layer off composition shingles and most roofing manufacturers will void the warranty if it's been pressure washed. Once the roof is clear of loose debris, we apply a liquid moss treatment that kills the remaining moss and slows down regrowth. We also clean out every gutter run, check all the downspouts for proper flow, and include downspout strainers with every roof cleaning to keep downspouts flowing free. We haul away all the debris and you'll get photos documenting the full job so you can see exactly what changed.
Best Exterior Cleaning
How We Clean Asphalt Roofs Without Causing Damage
At Best Exterior Cleaning, we clean asphalt roofs using methods that follow Asphalt Roofing Manufacturers Association guidelines, helping protect roof life, shingles, gutters, and surrounding landscaping. We never use a pressure washer on asphalt shingles because it can remove protective granules and shorten the life of the roof. Instead, we remove heavy moss carefully by hand brushing, clear debris from valleys and drip edges, and use air to remove loose material safely. On steeper or more complex homes, including multi-level properties common in Bellevue, Kirkland, and Mercer Island, we use roof harness systems, extension tools, and drone assessments when needed to plan safe access. After cleaning, we apply a rain-activated moss treatment designed for Pacific Northwest conditions. This treatment works gradually over time, reaching moss spores deep in the shingle surface without damaging the roof.
Best Exterior Cleaning
What Happens When Roof Moss Gets Ignored
We've seen what happens when roofs go 5 or 6 years without a cleaning in this climate. Moss roots work their way between and underneath shingle tabs, holding moisture flat against the roof deck. That moisture has nowhere to go, so the decking starts to soften. We've pulled up sections on homes in Woodinville and Lake Forest Park where the plywood underneath was spongy and dark from years of trapped water. At that point you're past a cleaning and into structural repairs. A cleaning runs $400 to $700. A roof replacement runs $10,000 to $30,000 or more. Getting it cleaned every couple years is a pretty straightforward way to avoid a much bigger bill down the road.
Best Exterior Cleaning
Roof Types We Clean Across King County and Snohomish County
Most homes in King County and Snohomish County feature durable composition or asphalt shingle roofs. However, the protective granule layer on these shingles can wear down over time, a process often accelerated when persistent moss or debris is left sitting on the surface. We also clean metal roofs and adjust our process and treatment products based on your roof's material. Most homes around here do well with a cleaning every 1 to 2 years. If you've got heavy tree canopy or a lot of north-facing roof area, you might need it every 6 months. Spring and early fall are the best windows to book because the seasonal rain helps the treatment spread and do its job.
Best Exterior Cleaning
Why Homeowners Choose Us
We're owner-operated and based in Redmond. Fully licensed, bonded, and insured in Washington state, BBB accredited with an A+ rating, and 4.9 stars across 91 Google reviews. Homeowners across King County and Snohomish County keep calling us back because we respond fast, show up when we say we will, and give a clear price with nothing tacked on after. We send before-and-after photos with every job so you can see exactly what changed. If your gutters clog within 3 months of our service, we come back and clear them at no charge.
OUR REVIEWS
Checkout what our customers say about us!
Best Exterior Cleaning
Bundle Roof Cleaning With Gutter Cleaning, Pressure Washing, and More
If you're already getting the roof taken care of, it's a good time to knock out a few other things while we're there. We handle gutter cleaning, driveway and sidewalk pressure washing, deck and patio cleaning, siding wash, window cleaning, skylight cleaning, and solar panel cleaning. Bundling saves you money compared to booking each one separately. A lot of homeowners schedule a full exterior cleaning when they're prepping to sell, wrapping up after the rainy season, or just want the whole place cleaned up at once.
Best Exterior Cleaning
From First Call to Final Walkthrough
You call or fill out the form on our website. In some cases, we can give an estimate over the phone in minutes, then email it to you. Or we set up a time to come look at the roof. We walk the property, check everything, and give you one flat number on the spot. Once you're good to go, we schedule the work, usually within a couple of weeks during the busy months or within a few days the rest of the year. On the day of, we show up on time, work through the full job, bag and haul everything, and walk you through the results before we leave.
Pricing
Roof Cleaning Cost in King County and Snohomish County
We give you one flat price based on your roof. No per-square-foot surprises. Every tier includes moss removal, treatment, gutter clearing, and a 3-month guarantee.
Small One-Story Home
$400 to $600
Standard pitch, under 2,000 sq ft of roof area
- Moss and debris removal
- Moss treatment application
- Gutter clearing and downspout check
- All debris bagged and removed
- Before and after photos
- 3-month gutter guarantee
Medium Two-Story Home
$500 to $800
Moderate pitch, 2,000 to 3,500 sq ft of roof area
- Everything in Small tier
- Multi-level access setup
- Extended treatment coverage
- Detailed roof condition notes
- Priority scheduling available
Large or Complex Roof
Custom Quote
Steep pitch, 3,500+ sq ft, or heavy moss coverage
- Everything in Medium tier
- Drone assessment for planning
- Harness and safety rigging
- Phased cleaning if needed
- Full written condition report
What moves the price? Roof square footage, pitch, moss severity, and access difficulty. Minimum service is $450. Bundle with gutter cleaning, pressure washing, or window cleaning for combined pricing.
Frequently Asked Questions
Roof Cleaning FAQs for King County and Snohomish County
Cost, Timing, and Scheduling
Methods, Safety, and What to Expect
Moss, Damage, and Long-Term Roof Care
Pricing Transparency, HOAs, and Guarantees
Service Areas
Where We Work
We're based in Redmond and clean roofs throughout King County and Snohomish County. Most of our work is on the Eastside and south Snohomish County. We can typically reach any job site within 30 minutes.
King County
Redmond, Kirkland, Bellevue, Sammamish, Woodinville, Bothell, Kenmore, Mercer Island, Issaquah, Newcastle, Renton, Shoreline, Medina, Clyde Hill, and surrounding areas.
Snohomish County
Edmonds, Lynnwood, Mountlake Terrace, Mill Creek, Mukilteo, Everett, Marysville, Snohomish, Lake Stevens, Monroe, Brier, Maltby, and surrounding areas.
Don't see your area listed? Contact us and we'll let you know if we can get to your area.