Roof Soft Washing in Mt. Juliet, TN

Those black streaks on your roof aren't soot or shingle deterioration — they're Gloeocapsa magma, a cyanobacteria that feeds on the crushed limestone in asphalt shingles. Left untreated, it retains moisture against the shingle surface, accelerates granule loss, and shortens the life of the roof. In Wilson County's humid climate, GM spreads from north-facing sections to the entire roof within a few seasons. It also darkens the roof surface, which increases heat absorption and can drive up cooling costs.

The only safe and manufacturer-endorsed method for removing Gloeocapsa magma and roof algae is soft washing — low-pressure application of a diluted sodium hypochlorite solution with appropriate surfactants. This is the method recommended by the Asphalt Roofing Manufacturers Association (ARMA). High-pressure washing on shingles strips granules, voids manufacturer warranties, and shortens the roof's lifespan. We exclusively use the ARMA soft wash method: no pressure on the shingle surface, period.

Our process: we apply a low-pressure soft wash solution from the eave to the ridge, allow it to dwell on the shingles, and rinse gently. The sodium hypochlorite kills the biology at the root. Most shingle surfaces show immediate improvement in color — the black streaks and green algae disappear on contact as the chemistry works. Some deeply stained roofs show continued improvement over 2–4 weeks as rain washes away the dead organic matter.

We take precautions for every roof job: gutters and downspouts are flushed after treatment, all landscaping is pre-wetted and rinsed during and after treatment, and we use no pressure that could damage or dislodge shingles. If you have a solar panel array, we can work around the panels and treat accessible sections. We provide free estimates and can assess your specific roof's condition and slope during the visit.