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San Juan Islands roofing

Moss Treatment & Roof Cleaning in the San Juan Islands

Kill the moss, protect the roof — the PNW way, without a pressure washer.

Moss Treatment & Roof Cleaning in the San Juan Islands, Washington

Moss is the number-one roof killer on shaded island roofs. It holds moisture against the shingles, lifts them, and rots the deck underneath. Our damp, tree-covered north slopes on Orcas and San Juan grow it fast.

We treat moss with the right products and gentle low-pressure methods — never a high-pressure washer, which strips granules and voids shingle warranties. To keep it from coming back, we install zinc or copper strips near the ridge; every rain releases ions that inhibit new moss and algae growth.

The island difference

Under Orcas’ firs, moss is a when-not-if problem. A yearly treatment costs a fraction of the deck rot it prevents.

What’s included

  • Low-pressure, granule-safe cleaning (no pressure-washing shingles)
  • Targeted moss & algae treatment
  • Zinc / copper ridge strips to prevent regrowth
  • Gutter clearing & debris removal
  • Annual maintenance plans for shaded roofs

Typical island range

$400–$1,600

Gentle treatment + cleaning for an average roof. Heavy moss, steep pitch, and multi-story access raise the range.

General estimate for a typical island home — not a quote. Inspections & written estimates are free.

Where we do it

Moss Treatment & Roof Cleaning across San Juan, Orcas, Lopez & Shaw Islands — plus the outer islands of San Juan County.

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