Modesto, CA
Roof Cleaning in Modesto, CA
We clean Modesto roofs with a no-pressure soft wash: a sodium-hypochlorite-based solution applied gently that kills the algae causing black streaks, then a controlled rinse. High pressure never touches a roof, because it strips shingle granules and cracks tile. Call (209) 624-6249 for a free written quote.
Why Modesto roofs streak and grow moss
The black streaks on Modesto roofs are Gloeocapsa magma, an algae that feeds on the limestone filler inside asphalt shingles. Tule fog gives it months of damp mornings to spread, and orchard dust settling on the roof gives it extra nutrients. Shaded roofs under the mature trees around downtown and Graceada Park also grow moss, which holds moisture against the roof and shortens its life. None of this washes off in the rain, because the organism is rooted into the surface.
Soft wash only, no exceptions
A pressure washer on a roof is a roofing bill waiting to happen. High pressure strips the protective granules off asphalt shingles, cracks concrete and clay tile, and drives water under the roofing where it rots decking. Our soft wash applies the cleaning solution at little more than rain pressure, lets the chemistry kill the growth, and rinses gently. The streaks disappear and the algae is dead at the root, so it stays gone far longer.
Shingle and tile, older and newer
Modesto housing splits between composition shingle on much of the older stock and concrete tile across the newer northeast subdivisions. We soft wash both, with foot traffic kept off tile wherever possible since walking tile is what cracks it. Gutters get flushed as part of the job so the loosened debris does not sit in your drainage.
Protect the roof you have
A roof is the most expensive surface on the house, and algae and moss genuinely shorten its service life by holding moisture and eating filler. Cleaning every few years costs a fraction of early replacement. It also matters at sale time, because streaked roofs get flagged in inspections and drag down curb appeal photos.
Questions We Actually Get
What are the black streaks on my roof?
Gloeocapsa magma algae feeding on the limestone filler in your shingles. It spreads during Modesto's damp, foggy winters and will keep growing until it is killed with a proper soft wash treatment.
Do you pressure wash roofs?
Never. High pressure strips shingle granules and cracks tile. We use a no-pressure soft wash that kills the growth chemically and rinses clean.
How long does a roof cleaning last?
Typically several years. Because the soft wash kills algae at the root rather than rinsing the surface, regrowth is slow even with Modesto's foggy winters. Shaded roofs may need attention a bit sooner.
Can you clean the tile roofs in northeast Modesto?
Yes. Concrete tile is common in the newer subdivisions off Highway 99, and we soft wash it with methods that keep foot traffic and pressure off the tile, since both cause cracking.
Ready to make it look new again?
Fast scheduling. Photo-documented results. A written quote before any work starts.