Roof washing removes the black streaks, algae and moss on asphalt shingles using low-pressure application and a careful rinse, not a blast. Barrington, IL roofs sit under heavy tree cover, which keeps slopes damp and streaked. Rob, owner of the Woodstock-based family business Rob's Exterior Services, handles it himself from $250. Text a photo of the roof to (815) 451-0106 for a free quote.
The dark streaks fanning down many shingle roofs are not soot, and they are not ordinary dirt. They are most often Gloeocapsa magna, a type of algae that colonizes asphalt shingles, and it spreads fastest where a roof stays damp. A lot of Barrington roofs fit that description.
The tricky part is that the roof you see from the street is often the better side. The shaded back slope, the one over a porch, the one tucked beside a chimney, tends to look much worse. Rob uses that as the starting point: he wants photos of every slope before he quotes, and he tells you honestly whether washing makes sense or whether the roof is nearing replacement.
Why Barrington roofs streak on the shady side first
Algae and moss thrive wherever moisture and a thin layer of settled debris sit on the shingles. North-facing and shaded slopes stay wet longer, which is why the pattern is so consistent: lots of dark streaking on one side, cleaner shingles on the other. The village describes Lake Street as tree-shaded, and big canopies are typical of the older neighborhoods.
Overhanging branches add leaves, twigs and pollen to the mix, and the debris traps even more moisture against the roof. Moss tends to take hold in the creases where debris collects, at the base of valleys, around chimneys, and along the lower edges. Trimming back branches is the single best long-term step, and Rob will say so if he sees limbs sitting right on the shingles.
Low pressure only, and why that matters for shingles
Manufacturers and trade groups tend to favor gentle cleaning for asphalt shingles, and caution that forceful spray can knock off the granules that protect the shingle. Those granules are not decoration; they shield the asphalt from sun. Once they are gone, the roof ages faster.
That is why Rob sprays a mild solution, gives it time on the algae, and rinses softly from the top. He does not scrub or blast. Our guide on whether roof washing is safe for shingles walks through what to ask any contractor. If a roof is already shedding granules heavily, he will tell you washing will not help.
- Low-pressure solution application, not high-pressure blasting
- Rinse from the ridge down so runoff sheds naturally
- Gutters and landscaping protected during the work
- Honest word on granule loss before anything is cleaned
Steep, tall and complicated: what Barrington rooflines ask for
Older Barrington houses can have steep pitches, multiple gables, dormers and porch roofs at different heights. A simple ranch roof is one job and a three-story Queen Anne with a tower roof is another. Rob looks at pitch, height, access and what is beneath the eave before quoting, because some roofs take much longer than others.
If a roof is too steep or too fragile to walk safely, he will say it plainly, and may suggest cleaning only the accessible slopes. Safety is not negotiable. The quote reflects the real conditions, which is why he asks for photos from the ground and, if you have them, from an upstairs window.
When to call a roofer instead of a roof washer
A wash cleans a roof and nothing more. Where shingles are curled, cracked, missing or bald in spots, cleaning will not bring them back and may expose problems you would rather know about. Likewise, any soft decking, sagging, or interior leaks need a roofer, not a washer.
Rob would rather tell you that than sell a wash. A roof on its last legs can look cleaner after a wash, but it has not become newer. If your home is going on the market, a clean roof helps first impressions. If the roof needs replacing, a buyer's inspector will find that anyway. Photos of the whole roof help him give a straight answer.
- Curled, cracked or missing shingles
- Bald patches where granules have worn away
- Soft spots or sagging along the ridge
- Water stains on ceilings below
Moss, lichen and what a second visit looks like
Moss grows in thick mats and holds water against the shingle. Lichen clings tightly and can take more than one treatment. Rob treats moss gently, since pulling it up by force tears at shingles. Often the biological growth continues to die back over several weeks after treatment, so the roof keeps improving after he leaves.
Stubborn lichen sometimes needs a repeat visit, and he will tell you if that looks likely. Preventive steps help: trimming branches, keeping gutters clear, and checking the shady slopes each year. A clean, open roof dries faster, and that slows regrowth.
Planning the trip from Woodstock
Rob makes the trip from Woodstock, a drive of about thirty miles that seldom takes less than forty minutes. Roof work pairs naturally with gutter cleaning, since runoff from the roof washes grit into the troughs, and it makes sense to clean in that order. A soft wash of the siding is another common companion.
Roof washing goes smoothest in mild, dry weather. Expect the work to be scheduled for spring through fall. Text photos to (815) 451-0106 and Rob will tell you which slopes concern him most.
Roof Washing through the year in Barrington
Spring
Check the shady slopes for new moss after winter. Cleaning now keeps the growth from spreading through summer humidity.
Summer
Good conditions for roof work: warm, dry days. Streaking spreads quickest in humid stretches, so shaded slopes may darken noticeably.
Fall
Clear leaves from valleys before they mat. A wash in early fall lets the roof dry before cold weather and leaf drop.
Winter
Washing waits for warmer weather. Meanwhile, scan from the ground for ice dams, icicles and damaged shingles, and line up spring work.
Getting a quote
Few parts of a house cost more to replace and get less attention than the roof, so keeping it clean and dry pays off. Send Rob photos of your Barrington roof from the ground, including the shady side, by texting (815) 451-0106. He will tell you what the streaks are, whether washing helps, and, if it does, how he would go about it.