Home › Recent Projects › Roof and Gutter Cleaning in Bothell, WA (Zinc Sulphate, Mossy Hips)
Squatch Roofing cleaned the roof and gutters on a home in Bothell, WA 98021 on July 27, 2026, spreading zinc sulphate powder over a tan laminate shingle roof. The July 21 inspection found moss growing along the hips and in the course lines of one facet, and a cracked, peeling block chimney that was documented but left out of scope. The job had two line items: the zinc sulphate roof cleaning and a gutter cleaning.
| Location | Bothell, WA 98021 |
|---|---|
| Service | Roof and gutter cleaning: zinc sulphate powder plus a gutter cleaning |
| Property | Hip roof with a painted block chimney, pipe vents, box vents, and a back deck below one eave |
| Existing roof | Tan laminate asphalt shingles |
| Inspection | July 21, 2026: attic and roof (12 photos) |
| Findings | Moss along the hips and in the course lines of one facet; cracked, peeling paint on the chimney block (out of scope) |
| Treatment | Zinc sulphate powder, priced per square of roof (the square count is not recorded in the job file) |
| Work date | July 27, 2026, one visit |
| Project investment range | $700 to $1,000 |
What Squatch Found on the Inspection
The inspection on July 21, 2026 started in the attic and finished on the roof.
- Moss: green moss growing along the hip lines and filling the course lines across one facet of the roof. The rest of the tan laminate field looked clean by comparison.
- Chimney: a painted concrete block chimney with a crack running through the block and the paint peeling off near the roof line, above its metal flashing.
- Attic: the underside of the plywood deck, the rafters, and a reflective foil layer laid over the attic floor.
The chimney is not on this job’s invoice. It was photographed and reported so the homeowner knew about it.
What We Recommended
The moss on this roof was concentrated on the hips and one facet, growing on top of a shingle field that the inspection photos show intact. That called for a cleaning, not a repair. Squatch quoted a zinc sulphate treatment priced per square of roof, plus a gutter cleaning, and the homeowner approved both.
How the Cleaning Was Done
July 27: one visit, six days after the inspection. The crew first photographed the roof as they found it: the vents and pipe flashings, the chimney, and the gutter running along the eave above the back deck, which was empty of debris in that frame. The next set shows zinc sulphate spread over the slopes, heaviest along the hips and ridges and down the facet that carried the moss.
The gutter cleaning is on the invoice, but the photo log has no before shot of the gutters, so this post does not describe what came out of them.
The Finished Result
By the end of the visit the hips, ridges, and the mossy facet all carried a coat of zinc sulphate. The white streaks in the after photos are the dry powder, left on the roof for rain to carry down the slopes. There is no later photo on file showing the moss after the rain, so this post does not claim how fast it cleared.
What This Roof Cleaning Cost
Project investment range: $700 to $1,000. This range reflects the scope of this completed project and is not a current quote. It is anchored on the final invoice total, which includes Washington sales tax.
The zinc sulphate line is priced per square of roof, so the roof’s size set most of the price. The gutter cleaning is the second line. No repairs or sealant were billed on this job.
What Homeowners With Similar Roofs Should Know
Moss picks its spots. On this roof it grew along the hips and on one facet, while the rest of the field stayed mostly clear. Look at the hips and the shadier facets first.
A white roof right after treatment is expected. Zinc sulphate goes on as a dry powder and stays visible until rain moves it.
The inspection covers more than the moss. The cracked chimney block was photographed and reported even though this job only covered cleaning.
Related questions
How much did this roof cleaning in Bothell cost?
The project investment range was $700 to $1,000 for a zinc sulphate roof cleaning priced per square of roof, plus a gutter cleaning. The range reflects this project’s scope and is not a current quote.
Where was the moss on this roof?
Along the hip lines and in the course lines of one facet, as the July 21 inspection photos show.
Why is the roof white after the cleaning?
The white streaks are the zinc sulphate powder. It is left on the roof for rain to carry down the slopes.
Were the gutters cleaned too?
Yes. A gutter cleaning is the job’s second line item. The photo log shows the gutter along the back deck empty on treatment day but has no before photo of the gutters.
How long did the job take?
One visit on July 27, 2026, six days after the July 21 inspection.
Have a roof with similar symptoms?
If moss is creeping along your hips or filling the course lines on one side of the roof, Squatch Roofing can run a free 21-point inspection, show you the photos, and tell you whether a roof and gutter cleaning, a SasWash, or a repair fits your roof. Squatch serves Bothell, the Eastside, and the greater Seattle area. Related projects: the Kirkland zinc sulphate and gutter cleaning and the Redmond zinc sulphate cleaning for moss in the course lines. Schedule an inspection or call (425) 292-8327.
This project documentation was prepared by Squatch Roofing from the job records and photos from our crew, October 2026. Technical review by Ben Metsker, Manager, Squatch Roofing.
