Most people who search for roof pressure washing want the dark streaks gone. We get that. On asphalt shingles the streaks are usually a cyanobacterium called Gloeocapsa magma, which feeds on the limestone filler in the shingle and spreads on the wind, as the Asphalt Roofing Manufacturers Association explains. Tile, flat, and metal roofs grow algae and mildew of their own.
High pressure takes the protective surface off and can push water under the roof. We use a soft wash instead: low pressure, and a roof-safe cleaner that does the actual work.
High-pressure blasting compared with low-pressure soft wash on a roof| On your roof | High-pressure blasting | Our low-pressure soft wash |
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| Shingles | Knocks off protective granules. | Granules stay in place. |
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| Algae and mildew | Roots stay and streaks return sooner. | Cleaner kills growth at its base. |
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| Water intrusion | Can force water under the roof surface. | Gentle flow that follows the way rain runs. |
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| Tile, flat, and metal | Can chip tile and scar coatings and membranes. | Safe on tile, flat roofs, metal, and shingle. |
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Kendall roofs are mostly concrete tile, with shingle on older single-family streets and flat roofs on condo and townhome buildings. Heat and humidity grow algae and mildew on all of them. On tile we stay far below the 1,200 psi ceiling tile care guides set, use a concrete-compatible cleaner, and step only where tiles overlap. On flat sections we use a membrane-safe cleaner and clear the drains and scuppers so water actually leaves the roof.
Kendall is inside Miami-Dade County's High-Velocity Hurricane Zone, and roofing products installed here need a Miami-Dade Notice of Acceptance. We clean roofs. Repairs, re-roofing, and any work an HOA needs to approve belong to a licensed roofer and the association's process. The age spread matters for roof washing too: a 1970s single-family roof and a 2000s townhome roof installed thirty years apart can sit on the same street, and we check the installation era before picking a cleaner, since older roofing materials sometimes need a gentler approach than current products do.
Most roofs do well with a wash every two to three years. Shaded slopes and roofs under trees grow algae faster and may need it sooner. A damp, algae-covered roof also sheds more grit into the gutters below, which is one more reason we handle both in a single visit.
See how our roof washing works in Kendall