Before and after: black streaks removed from an asphalt shingle roof in Frankfort, IL. No pressure was used on the shingles.
Short version: a Frankfort homeowner found us through our Google reviews, told us about dark streaks on the roof and green growth on the siding, and got a quote the same week. We treated the roof and soft washed the house the following week. The streaks are gone, the siding is clean, and the homeowner is now looking at a Clean Club plan so it stays that way.
The Call
How the Frankfort homeowner found us
This one started the way a lot of our jobs start. The homeowner searched for a roof cleaning company near Frankfort, read through our Google reviews, and picked up the phone. They were not shopping five companies. They read what other homeowners in the area said about our crew and decided we were the ones to call.
The description was simple. Dark streaks running down the roof, worse on the north facing side, and a bit of green showing up on the siding. Both of those are extremely common on homes in Frankfort and the rest of Will County, and both have the same root cause.
The Diagnosis
What those black roof streaks actually are
Homeowners usually call them dirt, soot, or worn out shingles. They are none of those. Black roof streaks are a living algae called Gloeocapsa magma. It feeds on the limestone filler in asphalt shingles and it holds moisture against the roof surface. The north and shaded sides stay damp longer, which is why the streaking almost always shows up there first.
The green on the siding is the same story in a different spot. Algae and mildew settle on the north and shaded elevations of the house, especially near landscaping, gutters, and anywhere the sun does not reach for long.
- Streaks were heaviest on the shaded roof planes
- Light green film across the lower siding on two elevations
- Shingles were in solid shape with plenty of life left
- No pressure washing was appropriate on either surface
The Quote
Quoted in a day, booked for the following week
We measured the home using satellite imagery and sent the homeowner a written quote without needing to schedule a walkthrough. That saves everybody a trip and it is one of the reasons our customers in Frankfort, Mokena, and New Lenox get an answer the same day they call.
The quote covered a full roof treatment plus a house wash on all four sides. The homeowner approved it and we put them on the schedule for the following week, which was this week.
The Work
Soft washing the roof and the siding
Roof cleaning is not pressure washing. Running a pressure washer across asphalt shingles strips the granules off the surface and takes years off the life of the roof. It is one of the fastest ways to turn a cleaning job into a roof replacement.
Instead we apply a cleaning solution at low pressure that kills the algae at the root. The roof is treated, the solution does the work, and rain finishes rinsing the dead growth off over the following days. Landscaping and plantings get saturated with water before, during, and after the treatment so nothing around the house takes a hit.
The house wash used the same soft wash approach at a strength suited to vinyl siding. We cleaned the siding, trim, soffits, and gutter faces, then rinsed the whole house down from top to bottom.
- Roof treated with a low pressure soft wash application, no walking damage, no granule loss
- All plantings and grass pre soaked and rinsed after
- Siding, trim, and gutter faces washed and rinsed
- Windows and doors checked and protected before the wash started
The Result
Streaks gone, siding clean, homeowner happy
The difference on the roof is the part everybody notices first. The dark streaking is gone and the shingles read as one even color again from the street. The siding came back to its original shade with no green left along the bottom courses or in the shaded corners.
The homeowner was happy enough with the job that they are now considering the Green Pro Clean Club so the house never gets to that point again. That is the whole idea behind the program. Instead of waiting until the algae is visible from the road, members get their exterior handled on a schedule.
- One annual house wash
- Spring and fall gutter cleaning
- Bi annual window cleaning, one full interior and exterior visit plus one exterior visit
- All concrete and patio flatwork cleaned once a year
- 15% off everything else, including roof cleaning and Christmas light installation
- Priority scheduling ahead of one time customers
Local Service
Roof cleaning and house washing in Frankfort, IL
Frankfort has a lot of mature trees, shaded lots, and homes that hold moisture on the north side well into the afternoon. That combination is exactly what algae wants. Most homes here need a roof treatment every three to five years and a house wash about once a year to stay ahead of it.
If your roof has the same streaking, you can see the rest of what we do in the area on our Frankfort power washing page, or call us at (815) 650-0397 and we will get you a number.
Common Questions
Roof cleaning questions from Frankfort homeowners
Not the way we do it. We soft wash, which means the cleaning solution does the work at low pressure. Pressure washing a shingle roof strips granules and shortens the life of the roof, so we never do it. Soft washing is the method recommended by asphalt shingle manufacturers.
A lot of the change shows up right away. The rest continues to lighten over the next few weeks as rain rinses the dead algae off the shingles. On heavily streaked roofs the final result usually settles in within a month.
Yes, when the crew takes the right steps. We saturate all plants, shrubs, and grass with water before we start, keep them wet during the job, and rinse everything again when we finish. Dilution is what protects the landscaping and we plan for it on every roof.
About once a year for most homes. Houses with heavy shade, nearby trees, or a north facing wall that stays damp may show growth sooner. Roof treatments generally last three to five years depending on shade and tree cover.
Usually not. We measure your home from satellite imagery and send a written quote, often the same day you call. If the property has something unusual going on we will come take a look before we give you a number.
We do. Green Pro Services covers Kankakee County and Will County, including Mokena, New Lenox, Monee, Manteno, Bourbonnais, Bradley, Orland Park, and Olympia Fields.
Got Streaks On Your Roof?
Get a written quote for roof cleaning and house washing in Frankfort and across Will County. Most quotes go out the same day.
Exterior cleaning and holiday lighting for homes and businesses across Kankakee County and Will County, Illinois.
407 S. Yates Ave
Kankakee, IL 60901
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