Asphalt Shingle Roof Cleaning
Those dark streaks on an asphalt shingle roof are usually algae, not dirt — and they need a soft, non-pressure wash to remove safely.
What's actually causing the streaks
The dark streaking common on asphalt roofs is typically a blue-green algae that feeds on limestone filler in the shingles. It spreads fastest on shaded, north-facing sections and in humid conditions.
Why pressure washing is the wrong tool
Asphalt shingles are coated with protective granules that shield the underlying material from UV. High pressure strips these granules, shortening the roof's life rather than extending it — and it's typically what voids a shingle warranty.
Our process
Low-pressure application of a roof-safe cleaning solution that kills algae at the root, an appropriate dwell time, then a gentle rinse. No scrubbing, no blasting.
Signs you need it
Dark streaking, moss in the valleys where roof planes meet, and green-tinted patches on shaded sections.
Frequently asked
Does roof cleaning void my shingle warranty?
Non-pressure soft washing is generally what manufacturers require to keep a warranty valid; high-pressure cleaning is usually what voids it. Check your manufacturer documentation.
How long does the result last?
Typically two to three years, depending on tree cover and shade.
Other roof cleaning surfaces
Where we work
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