Remove the black streaks, algae and mildew that are shortening your roof's life — safely, without high pressure.
Those dark streaks on your Florida roof aren't dirt. They're a living algae called Gloeocapsa magma — a cyanobacteria that feeds on the limestone filler in asphalt shingles. Left alone, it shortens your roof's usable life by up to 10 years, reduces energy efficiency (dark streaks absorb heat, attics run hotter, AC bills go up), and tells buyers "this house has been neglected" before they even walk inside.
Pressure washing a roof is never the answer. High pressure blows off the granules that protect asphalt from UV, cracks tile, voids manufacturer warranties, and makes the problem worse long-term. The only safe way to clean a roof is a professional soft wash — and that's what we do at Krystal Klean.
Our soft-wash roof cleaning process: we pre-soak landscaping around the house, often tarping delicate plants. We apply a professional algaecide solution to the entire roof at very low pressure (garden-hose level). The chemistry does the work — killing Gloeocapsa magma at the root, along with moss, lichen, and any other organic growth. After a short dwell time we gently rinse with low pressure. Landscaping gets rinsed and double-checked. Results often continue to improve over the following 1-2 weeks as dead algae fully releases from the shingles.
Every major shingle manufacturer endorses this approach. Our process meets the ARMA (Asphalt Roofing Manufacturers Association) standard. GAF, Owens Corning, CertainTeed — all explicitly require soft washing, not pressure washing, to keep warranties intact.
Every roof type: asphalt shingle (most common — soft wash with algaecide), tile (never pressure washed — cracks tiles and dislodges mortar — soft wash only), metal (gentle surfactant wash), flat roofs, slate, wood shake. Each requires specific chemistry and technique. Our technicians are trained on every roof type in Florida.
How long results last: typically 3 to 5 years on shingle roofs. We offer a 2-year spot-clean warranty. For coastal homes and homes under heavy tree cover, schedule every 3 years; everyone else, every 4-5.
Dunedin's historic downtown cottages and the coastal homes along the Causeway each have their own cleaning needs — we soft-wash the cottages, power-wash the newer concrete pool decks, and seal the pavers that cook under the sun.
Or see our full Dunedin service page for every exterior cleaning service we provide.
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Real jobs, real Tampa Bay properties.
422 verified Google reviews · 4.9★ average rating
"I couldn't be more impressed with the outstanding job Krystal Klean Exterior did on my house roof. Ben and his assistant were professional, efficient, and incredibly thorough from start to finish. They treated my home with care and delivered results that exceeded expectations. The roof looks fantastic—clean, refreshed, and better than ever."
"Absolutely fantastic! Staff very efficient and pleasant"
"Great company. Very polite and helpful workers that clearly knew what they were doing with excellent equipment. They did a fantastic job and made certain that we were totally satisfied with the job before leaving. I will definitely recommend them and seek them out next time I need to clean our tile roof."
"Excellent job done by the workers!"
4.9★ · 422 Google reviews · Fully insured · Same-day quotes
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