
Gentle on Stucco, Tough on Stains: House Washing in Powell, Ohio
September 25, 2026Those dark streaks running down a roof are one of the most common sights on Ohio homes, and one of the most misunderstood. Most people assume it’s dirt or aging shingles. It’s actually algae, and it keeps spreading until it’s treated. At a home in Columbus, Ohio, Clean Life Exterior Cleaning cleared the black streaks off a shingle roof and brought back an even, uniform surface.
What Those Black Streaks Really Are
The dark streaking you see on so many roofs isn’t dirt, and it won’t rinse off on its own. It’s algae that feeds on the shingles and spreads across the surface over time, leaving behind the blotchy, streaked look that ages a home. This roof had developed exactly that: dark patches and streaks spreading unevenly across the shingles, standing out sharply against the lighter trim and siding.
Left untreated, the algae keeps growing. Beyond the look, that kind of buildup can hold moisture against the shingles and contribute to wear over time.
A Safe Soft Wash, Never High Pressure
Here’s what matters most with roof cleaning: you can’t blast it clean. High pressure tears up shingles, strips the protective granules, and shortens the life of the roof. The streaks might come off, but so does the surface you’re trying to protect.
We cleaned this roof with a soft wash method, the industry-standard approach for shingles. It starts with clearing loose debris, followed by a biodegradable algaecidal treatment applied at no pressure. The treatment breaks down the algae and other growth at the source, then a light rinse finishes the job. The roof gets clean without any of the damage high pressure would cause.
An Even Roof Again
The difference speaks for itself. With the algae treated, the streaks are gone and the shingles read even and uniform across the whole roof. One thing worth knowing: black streaks fade quickly after the first rain, while heavier moss or algae can take a few months to fully release. Either way, the home already looks dramatically sharper from the street.
Why Roof Cleaning Is Worth It
Treating a roof does more than clear the streaks:
- Removes the algae that causes black streaking, at the source
- Uses no-pressure soft washing that protects the shingles
- Helps extend the lifespan of the roofing by clearing buildup
- Restores an even, uniform look that lifts the whole home’s curb appeal
Ready to Clear Your Roof?
If black streaks have taken over your roof, a professional soft wash clears them safely, without the damage high pressure causes. Clean Life Exterior Cleaning handles roof cleaning across Columbus and the surrounding area with a method built for shingles.
A clean roof does more than look good. It protects one of the biggest investments in your home.




