Black Streak Removal in Columbus, Ohio

Black streaks are caused by Gloeocapsa magma, a cyanobacterium that grows on the crushed limestone filler in asphalt shingles. It produces a dark pigmented sheath to protect itself from UV radiation — that's the black color you see. It's not dirt, mold, or tree sap. It's a living organism that spreads across your roof over time.

Yes. The algae feed on the limestone in your shingles, gradually breaking down the granule layer that protects against UV damage. As the protective layer thins, shingles become brittle, crack, and fail prematurely. Left untreated, algae can reduce your roof's lifespan by 5-10 years. Read our detailed breakdown.

No — and doing so will cause more damage than the algae. Pressure washing physically blasts away the protective granule layer on your shingles and can affect manufacturer warranty coverage. ARMA warns against pressure washing and recommends a non-pressure chemical treatment approach. See what manufacturers actually say.

Black streak removal in Columbus typically ranges from $600 to $1,600+ depending on roof size and pitch. Compare that to a roof replacement at $8,000–$20,000+ — treatment is a fraction of the cost. See our full pricing guide.

The algae begin dying immediately upon treatment. Homeowners see dramatic transformations by the time we leave. After treatment, the algae will be gone. Moss and lichen will be dead, but they may remain rooted around the granules. Forcing the dead growth off can pull granules from your roof. The gentlest approach is to let it dry and flake away through several sun-and-rain cycles. Before long, it will be gone without damaging the roof. Our 3-Year Bio-Free Guarantee covers you if streaks return.

Black streaks alone do not prove that a roof needs replacement. The roof's age, condition, leaks, and shingle damage all matter. Our free drone assessment will show you what's visible on your roof — algae or signs of actual damage — so you can make an informed decision. Read: Could cleaning save you $15,000?