We will not pressure wash your roof. Moss gets swept by hand with a soft bristle brush and treated instead, because a pressure washer damages roofing material even when a competitor calls it "soft wash."
Pressure washing a roof strips granules and shortens its life, even when a competitor markets the same equipment as gentle "soft washing." Speaks removes moss by hand with a soft bristle brush, then treats what remains with zinc sulfate monohydrate to kill the rest. Some low-profile moss stays visible right after the visit (we tell homeowners that upfront), and the treatment finishes the job over the following weeks. In the Pacific Northwest, moss is a recurring maintenance item, not a one-time fix; we're upfront about that too.
"Soft washing" is a real term in this industry, and it's also a sales pitch. It still runs a pressure washer over the roof, just at a claimed lower setting, and it still compromises the surface. Composition shingles lose granules under pressure, cedar shakes lose their weatherproofing layer, and either way, water starts finding its way in faster than it should.
We don't do it. Not as an upsell, not as an option if a customer really wants it. If a pressure-washed roof is non-negotiable for you, we'll tell you upfront that we're not the right fit, and we mean it. (Driveways and decks are a different story, that's what pressure washing is actually built for.)
A soft bristle brush clears heavy moss without disturbing shingles or shakes.
Zinc sulfate monohydrate kills the low-profile moss the brush can't fully remove.
Some visible moss remains right after the visit. That's expected, not a miss.
PNW moss doesn't fully go away. Think maintenance, not a fix nobody can deliver.
Moss traps moisture against the roofing material. A roof that never fully dries out stays damp longer after every rain, and composition shingles or cedar shakes both deteriorate faster under sustained moisture than they would in normal wear.
Left unmanaged for years, moss-driven moisture damage is a real path to replacing a roof early, often well before it would have otherwise worn out. Moss maintenance, done consistently, is a fraction of that cost, spread out over years instead of paid all at once early. A moss-heavy roof also sheds debris straight into the gutters below it, so most roof jobs make sense to pair with a gutter cleaning.
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"No streaks from Speaks! Speaks Window cleaning did such an amazing job with my windows. It was a big job..."
"John and his guys are great! They just cleaned all of our windows inside and out. Very pleased with the quality and attention to detail. Fair price and great work!"
"Great job (roof, gutter and window cleaning)! Good value. Highly recommend."
The questions we hear most about roof moss and why we won't pressure wash, answered straight.
Call (206) 228-5069 or request a free estimate. John usually calls back the same day.