Roof cleaning in Charleston, SC should remove black streaks and green growth without harming shingles or metal. We soft wash roofs at low pressure, so the roof looks cleaner and its surface stays intact.
The dark streaks running down so many Lowcountry roofs aren’t dirt, and they aren’t a sign of a leak. They are usually a hardy airborne algae, often identified as Gloeocapsa magma, that thrives in warm, humid climates. It travels from roof to roof on the wind and darkens over time as it builds a protective coating against the sun.
Left alone, the algae — and the moss or lichen that can follow it — holds moisture against the roof surface, which can shorten the life of the shingles. Shaded roofs under live oaks and roofs on marsh-front homes, where humidity barely lets up, tend to streak first.
The answer isn’t pressure. Asphalt shingles are protected by a layer of mineral granules, and high-pressure water can strip them away; roofing manufacturers broadly caution against it. Instead, we soft wash: a cleaning solution applied at low pressure kills the algae, and a gentle rinse carries it off. It’s the same principle behind our soft washing for siding, applied to the most exposed surface on your home.
Metal roofs, a familiar sight on island and beach homes, need care of a different kind: mildew, pollen and salt film rather than algae streaks, on painted finishes that shouldn’t be scrubbed. Roof cleaning is part of our complete Charleston pressure washing service, and it pairs well with window cleaning, since runoff inevitably reaches the glass below.
Every roof receives a method matched to its material, pitch and condition.
We soft wash architectural and three-tab shingles at low pressure, letting the solution kill the algae rather than forcing it off. Granules stay where they belong, and any faint staining that remains continues to fade over the following weeks as rain rinses away the dead growth.
Standing-seam and other metal roofs collect mildew, pollen and salt residue, especially within sight of the ocean. We clean them gently to avoid scratching painted finishes, paying attention to seams, fasteners and flashing as we work across each panel.
Moss and lichen hold moisture against roofing and can creep beneath shingle edges. Our treatment kills the growth so it releases gradually with the weather. We don't scrape or pry it off, which risks tearing or lifting the shingles underneath.
Roof runoff lands on plants, siding and windows. We pre-wet and rinse landscaping throughout the job, and rinse the siding, trim and glass beneath the eaves so cleaning solution doesn't sit on them once the roof is done.
Because our crew is on and around your roof, we note loose shingles, lifted flashing or soft spots we come across. When repairs are needed, our home repair team handles roof and gutter repairs as well, so you don't need to find another contractor.
Learn moreFree estimates · Licensed & insured · Trusted across the Lowcountry since 2008
We identify the roofing material, pitch and condition, look for damage, and decide whether the work is best done from ladders, the roof or the ground.
Plants are soaked, outdoor furniture is moved, and we plan how runoff will travel off the roof and away from sensitive areas.
The solution is applied evenly across the roof at low pressure and given time to kill algae, moss and mildew.
We rinse the roof where appropriate, then the landscaping, siding and windows below, and review the result with you before we leave.
Replacing a roof is a major expense, and a careless cleaning can bring that day closer. We approach roof cleaning conservatively: low pressure, careful footing and close attention to what's happening on the ground below. It's the same patience that has earned the trust of more than 4,000 clients since 2008.
Low pressure leaves the protective mineral granules on your shingles, and those granules matter for both the roof's appearance and its lifespan.
Roof work means height and wet surfaces. Our licensed and insured crews take that seriously on every pitch and every story of your home.
If a roof is close to the end of its life, we'll tell you plainly rather than recommend a cleaning that won't truly help.
Yes, when it is done at low pressure. High-pressure washing can strip the granules that protect shingles from sun and weather, which is why roofing manufacturers generally caution against it. Soft washing relies on a cleaning solution to kill algae and moss, followed by only a gentle rinse, so the shingle surface is left intact.
In humid climates like Charleston's, black streaks are usually caused by airborne algae that feed on the limestone filler found in many asphalt shingles. The streaks typically appear first on shadier, north-facing slopes and darken as the colony grows. They don't indicate a leak, but the growth holds moisture and is worth removing.
Many Lowcountry roofs benefit from cleaning every two to three years, though heavily shaded roofs and homes near the marsh can streak sooner. The best guide is appearance: when streaks or green growth return, it's time. Cleaning before the growth becomes heavy is easier on the roof and usually quicker.
Yes. Metal roofs don't develop algae streaks the way shingles do, but they do collect mildew, pollen and salt residue, particularly on homes close to the ocean. We clean them at low pressure with solutions suited to painted metal finishes, taking care around seams, fasteners and flashing.
We take several steps to protect them. Plants beneath the roofline are soaked with water before work begins, kept wet during application and rinsed thoroughly afterward, so runoff is diluted along the way. If you have delicate or prized plantings close to the house, point them out at the estimate and we'll cover them.
Most of the discoloration lifts on the day of cleaning. Heavier or older staining can take a few weeks to fade completely, as rainfall rinses away dead algae left in the texture of the shingles. This is normal with soft washing, and it's far better for the roof than forcing the staining off with pressure.
Call (843) 926-6554 or send a photo of your roof through our estimate form, and we'll recommend the safest way to clean it.
