Roof washing clears dark streaks and green growth from asphalt shingles by applying a cleaner gently and rinsing, not by blasting. In Richmond, IL the streaks usually trace to damp, shaded slopes under mature trees. Rob performs it himself in Richmond, IL, from $250. Text a photo of your roof to (815) 451-0106 for a free quote.
From the street, a dark roof looks like age. Look closer and the dark is often a living film sitting on top of the shingles. The common cause is Gloeocapsa magna, an algae that spreads along roof slopes in long vertical streaks, usually starting on the side that sees the least sun. In Richmond, with its older streets of tall trees and a creek that keeps the air damp, a lot of roofs get that treatment.
Many owners assume the only fix is a new roof. Sometimes that is true. Often it is not, and cleaning is a sensible way to improve how a roof looks and to stop a growth film from holding moisture against the shingles. This page covers how Rob decides, what he does, what he refuses to do, and when to call a roofer instead.
Reading a Richmond roof from the ground
Before he gets near a ladder, Rob looks at the roof from the street and the yard. The pattern of the stain tells him a lot. Streaks on the north and east faces point to algae. Fuzzy green patches in the valleys and under tree limbs may be moss, which is a different problem and grips harder. Bare, shiny, shedding patches mean granule loss, and that is not something cleaning can restore.
Richmond homes vary a great deal in roof age and type. Older village houses sometimes have been reroofed several times, with a combination of pitch changes, dormers and porch roofs. Newer homes have simpler gable roofs with architectural shingles. Each stain pattern comes from the same few causes, but the right approach depends on what the shingles can take.
Send a photo from the yard that shows the whole roof face, and a closer one of the worst area. That is usually enough for Rob to say whether it looks like a good candidate.
- Long dark streaks, north and east slopes: usually algae
- Thick green or brown cushions in valleys: likely moss
- Bare patches and loose granules in gutters: aging shingles
- Curling or cracked edges: a roofer's call, not a cleaner's
Why low pressure is the only way Rob washes a shingle roof
Asphalt shingles are a layer of granules stuck to asphalt. High pressure can blast the granules loose, expose the asphalt and shorten the roof's life. Roofing makers and trade groups point owners to gentle cleaning and warn off high-pressure spray, so for Rob a roof wash is always a soft wash. The Is Roof Washing Safe for Asphalt Shingles? guide covers the reasoning.
Rob applies a cleaning solution that kills the algae at the root, then rinses gently from the ridge downward. The streaks often fade over days or weeks rather than vanishing the moment the water stops, since the solution keeps working. He is careful not to flush water up under the shingle edges and keeps runoff away from shrubs and any garden beds below the eave.
He also does not stand on a wet roof where it is unsafe. If a slope is too steep or too slick, he will tell you, and the job may be limited to what he can do safely.
When to wash and when to call a roofer instead
A roof wash is for a roof with life left in it. Once shingles curl, crack, vanish or shed granules in quantity, cleaning has little to offer, and a wash could simply show you where the next leak will start. A roofer should look first. If you are within a year or two of replacing the roof, washing it is usually money better spent elsewhere.
Moss is a gray area. Light moss can be treated and rinsed. Heavy moss has roots that lift shingle tabs, and pulling it can damage them. Rob will be straight with you about what he can do and what would cause more harm.
Do not use a leaf blower and a ladder to chip at streaks, and do not use bleach from a garden sprayer. Both can harm shingles, plants and your gutters, and the stains return.
Shade, trees and the creek: where Richmond roofs go dark
Algae wants moisture and a bit of food. A roof under old maples and oaks gets both, as leaf litter and pollen sit in the valleys and drip lines stay damp. Houses close to Nippersink Creek tend to see slightly higher humidity, and the open farmland around the village means wind-blown dust and spores settle on roofs year-round.
Roofs with a steep north face and a big tree over them are the usual suspects. A south-facing slope with full sun may stay clean for years while the opposite face turns black, and that mismatch gives it away.
You can slow regrowth. Trim branches that overhang the roof, keep gutters clear so water moves off the edge, and clear leaf piles from valleys. Some roofs have zinc or copper strips near the ridge that help slow growth; those are installed by roofers and do not clean anything, but they can extend the time between washes.
What the day looks like
Rob checks the weather, since wind and rain affect how a roof wash goes. He protects plants and moves anything fragile out of the splash zone, then applies solution slope by slope. The roof edge, the gutters and the area below get rinsed afterward. Ask about clearing the gutters on the same trip.
Plan for streaks to continue fading after he leaves. Check the roof a couple of weeks later, and text him a photo if something looks off.
Roof Washing through the year in Richmond
Early spring
Snow melt shows which slopes stayed damp all winter. A look at the roof in April tells you if streaks have spread since fall.
Late spring
A dry, calm stretch after pollen settles is a good window for washing. Rob avoids windy days that carry runoff onto plants.
Summer
Roofs are hot, so cleaning solution works quickly, and Rob schedules around the heat of the day for safety.
Fall
Clear valleys of leaves before the first freeze. A roof that goes into winter clean has less trapped moisture to freeze and thaw.
Getting a quote
Nothing on a house costs more to replace than the roof, and little is harder to judge from the yard. Rob would rather tell you your roof is done than wash it and watch the shingles wear out early. If you are curious what the dark patches on your Richmond roof really are, text a picture to (815) 451-0106 and he will give you a straight answer about cleaning, timing and when it is time to bring in a roofer.