Those black streaks on Lancaster County roofs aren't dirt — they're Gloeocapsa Magma algae, and pressure washing will damage your shingles. Our soft wash roof cleaning service kills algae, moss, and lichen at the root using a low-pressure chemical treatment that's safe for asphalt shingles and won't void your roofing warranty.
The black streaks you see on roofs throughout Lancaster County — on homes in Lititz, Ephrata, Manheim, and everywhere else — are caused by a cyanobacteria called Gloeocapsa Magma. This organism thrives in humid conditions, feeds on the limestone filler in asphalt shingles, and spreads from one shingle to the next. Left untreated, it gradually degrades your shingles and shortens your roof's lifespan.
Moss growth is a separate but related problem. Moss is most common on north-facing roof sections and under overhanging trees — common throughout Lancaster County's heavily wooded neighborhoods. Moss holds moisture against the shingles, accelerating deterioration and eventually causing shingle lifting and water infiltration.
Pressure washing an asphalt shingle roof will strip granules, void your manufacturer warranty, and accelerate shingle wear. The roofing industry standard — and the ARMA (Asphalt Roofing Manufacturers Association) recommended method — is soft washing: applying a low-pressure cleaning solution (typically sodium hypochlorite-based) that kills organisms at the root, followed by a gentle rinse.
Results aren't always immediate — the dead algae and moss flush off the roof gradually over the next few rain events, typically within four to eight weeks after treatment. The roof won't look perfect the day we leave, but it will continue to improve for weeks afterward.
Pricing is based on roof size (squares), pitch, story height, and severity of growth. Steep or multi-story roofs in communities like Lancaster city, Lititz, and Ephrata cost slightly more due to access requirements. Call 717-807-7599 for a free estimate.
Soft wash roof cleaning results typically last two to five years depending on tree coverage, roof exposure, and climate. North-facing roofs and those under significant tree canopy may see regrowth in two to three years. South-facing roofs in full sun often stay clean for four to five years after treatment.
Serving Lancaster, Lititz, Ephrata, Manheim, Mount Joy, Elizabethtown, Millersville, Columbia, and all of Lancaster County.
717-807-7599 — Free Quote