Roof washing in Southwest Florida.

Those dark streaks running down a Southwest Florida roof aren't dirt, and they won't rinse away in a storm. They're gloeocapsa magma, a hardy blue-green algae that feeds on the limestone filler in shingles and thrives in the heat and humidity this close to the Gulf. Left alone it spreads into full black staining, and moss and mold move in behind it.

Roof washing is how we clear it, and the pressure is the whole point. A roof should never be blasted with a pressure washer. High pressure strips the protective granules off asphalt shingles, cracks the glaze on tile, and voids most roofing warranties. We soft wash instead, laying down a cleaning solution at low pressure that kills the algae at the surface, then rinsing gently. It's the same low-pressure approach we use for soft washing stucco, painted siding, and screen cages.

The solution does the work, not force. It kills the growth on contact, and over the next couple of weeks the rain carries the dead algae off while the roof keeps lightening back toward its real color. Because the organism is killed at the root rather than just knocked loose, a soft-washed roof stays clean far longer than one that was simply blasted.

Most homeowners pair the roof with a gutter cleaning on the same visit, since the algae and debris that stain the roof end up in the gutters anyway. Roof washing works as a one-time restoration or on a light recurring plan that keeps the growth from ever building back, and either way it starts with a straightforward instant quote.