COHOES, N.Y. – Aug. 24, 2026 – Near Me Exteriors, a roof cleaning and soft washing company based in Cohoes, is warning Capital Region homeowners that the black streaks appearing on asphalt shingles this month are a living algae, not dirt.
The streaks are showing up on roofs across Albany, Saratoga, Schenectady, Rensselaer and Warren counties, and late summer is when a full season of humid-weather growth becomes most visible from the street. The organism, Gloeocapsa magma, is a blue-green algae that consumes the crushed limestone filler used in most asphalt shingles. It spreads in humid conditions and appears as dark vertical streaks, usually worst on north-facing slopes and roof sections shaded by the heavy tree cover common across the region.
Once algae is established, moss and lichen often follow. Moss is the more destructive of the two. Its root-like structures work under shingle edges and lift them, and the mat of growth traps moisture against the roof long after the rain has stopped, where it can corrode nails and flashing.
“Most homeowners assume the streaks are just cosmetic,” said Forest Ward, owner of Near Me Exteriors. “By the time a roof looks bad from the street, the algae has been feeding on the shingles for a while. And if moss has taken hold, it is holding water against your roof every time it rains.”
Ward also cautioned homeowners against the most common do-it-yourself response: renting a pressure washer. High pressure strips the protective mineral granules off asphalt shingles. Those granules are the layer that shields shingles from sun and weather, and once they are gone the damage is permanent. Damage from pressure washing is also generally excluded from shingle manufacturer warranties.
“A pressure washer will make a roof look clean for a season, but it takes years off its life,” Ward said. “The right way to clean a roof is low pressure: a biodegradable solution is applied to kill the algae, moss and lichen at the root, then rinsed gently. That is the soft wash method, and it is the only method we will put on a roof.”
The company points to late summer and early fall as the practical window for roof cleaning in upstate New York. Summer growth is at its peak, roofs are dry enough to treat safely, and clearing moss now keeps it from trapping moisture against the roof through the wet fall and winter months ahead.
Homeowners can check their own roofs for three warning signs: dark streaks running down the slopes, green moss along shingle edges or in shaded sections and crusty gray-green lichen patches. Any of the three is a sign the roof is due for a professional cleaning rather than a coat of paint over the problem or a pass with a rented machine.
Near Me Exteriors performs low-pressure roof cleaning on asphalt shingle, metal and cedar roofs, along with house washing, gutter cleaning, window cleaning and other exterior cleaning services for homes across the Capital Region and the Glens Falls and Lake George area. The company offers free estimates and can usually assess a roof from photographs and a ground-level walk-around, with no one on the shingles until cleaning day.
About Near Me Exteriors
Near Me Exteriors is a locally owned exterior cleaning company based in Cohoes, New York, serving homeowners across Albany, Saratoga, Schenectady, Rensselaer and Warren counties. Founded in 2024, the company offers roof cleaning, soft washing, house washing, pressure washing, gutter cleaning, window cleaning, fence cleaning and exterior lighting installation. The company holds a 5.0 rating on Google with more than 50 reviews.
For a free estimate, call (518) 313-5082 or visit https://nearmeexteriors.com, and follow the company on Facebook.
Near Me Exteriors, 13 Green Mountain Rd, Cohoes, NY, (518) 313-5082
Media Contact
Company Name: Near Me Exteriors
Contact Person: Forest Ward
Email: Send Email
Phone: (518) 313-5082
Address:13 Green Mountain Rd
City: Cohoes
State: NY
Country: United States
Website: https://nearmeexteriors.com
Press Release Distributed by ABNewswire.com
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