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.
Seminole's tree canopy is a blessing and a curse — beautiful shade means constant mildew pressure on the north side of every home. Annual soft washing is the right move for most Seminole exteriors.
Or see our full Seminole service page for every exterior cleaning service we provide.
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422 verified Google reviews · 4.9★ average rating
"I had moved to South Carolina and the team came over and did a spectacular job making sure that everything was exactly as it needed to be. Work was exemplary I'm very happy thank you"
"Showed up quick and did the job fast and perfect. I am an estimator and did some math. Their prices are great!!"
"Our experience with Travis and Darrell was excellent. The job was completed to our satisfaction in such a short amount of time. We are impressed with the quality and professionalism of your company and it's employees. We will definitely recommend you to others and will be calling you for other services in the future."
"Very pleased. They did a great job! The guys were really pleasant to work with...smiling and friendly. I will have them back."
4.9★ · 422 Google reviews · Fully insured · Same-day quotes
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