The short answer
Those black streaks aren't dirt
The dark stains creeping down South Florida roofs are a living organism — Gloeocapsa magma algae — thriving in our heat and humidity. Left alone it spreads, holds moisture against the roof, and on shingle roofs actually consumes the granules, shortening the roof's life.
- Removes black algae streaks, mold, mildew and moss.
- Soft-wash (low pressure) — safe for tile, shingle and metal.
- Restores curb appeal and helps with HOA appearance standards.
- Reflective, clean surfaces run cooler than algae-darkened ones.
- A cleaning is also a chance to spot developing roof problems early.
Why never to pressure-wash a roof
High-pressure washing strips the protective granules off shingles and can crack or dislodge tile and force water under it — turning a cosmetic job into roof damage. We only soft-wash: a low-pressure treatment that kills the algae at the root so it stays gone longer, without harming the roof you're trying to protect.
The shingle industry says the same. The Asphalt Roofing Manufacturers Association warns that high-pressure washing systems are likely to damage asphalt roofing and should not be used to remove algae, and that brushes and brooms shouldn't be used either. It describes lightening the stains with a diluted household bleach (sodium hypochlorite) solution rinsed off with a gentle spray, says other chemicals or methods need the shingle manufacturer's approval, and encourages using professionals because the process makes the roof slippery.
When code enforcement can require a cleaning
Roof stains aren't only an HOA issue. Some Broward cities write roof appearance into their property maintenance codes, so a code officer can cite a streaked roof the same way they cite a mildewed wall.
In Coconut Creek, Code of Ordinances Section 6-36(a)(2) requires roofs, gutters and fascia to be cleaned or repainted and restored when 25% or more of any single sight view shows dirt, grime, stains, mildew, peeling or other deterioration. Margate's home maintenance standards require any exposed roof surface that becomes discolored or is scaling to be cleaned, repainted or re-covered with like material. If you've received a notice, a soft-wash cleaning is usually the fastest way to bring a tile or shingle roof back into compliance. We can also tell you whether the roof needs repair rather than cleaning.
Protecting your landscaping from soft-wash runoff
The cleaning solution that kills algae can also burn plants if it runs off the roof undiluted. We protect the yard as part of the job, not as an afterthought.
- Pre-wet the beds, shrubs and lawn along the drip line so the leaves and soil absorb clean water first.
- Cover delicate plants, koi ponds and outdoor furniture, and keep pets and kids inside while we work.
- Point downspout outlets away from planting beds while the solution is on the roof.
- Rinse plants thoroughly again once the roof is rinsed, so no residue sits on the foliage in the afternoon sun.
Official sources
Use these official sources to check current rules and requirements. What applies depends on your property, permitting authority and policy; cost ranges on this page are editorial planning estimates.
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Your questions, answered.
How much does roof cleaning cost in Coconut Creek?
Soft-wash roof cleaning typically runs $350–$900 for most homes — roughly $0.20–$0.60 per square foot — depending on roof size, pitch, material and how heavy the algae growth is. We give a free quote after a quick look at the roof.
Will cleaning damage my tile or shingle roof?
Not the way we do it. We use a low-pressure soft-wash method, never high-pressure blasting. Pressure-washing strips shingle granules and can crack tile or drive water underneath — soft-washing cleans safely and keeps the algae from returning as quickly.
Can the city make me clean my roof?
In some Broward cities, yes. Coconut Creek's Code Section 6-36(a)(2) requires roofs to be cleaned or restored when 25% or more of any single sight view shows dirt, stains, mildew or deterioration, and Margate's maintenance standards cover discolored or scaling roofs. HOAs often set their own appearance rules on top of that.