Will soft-washing void my shingle warranty?

No — we use ARMA-approved (Asphalt Roofing Manufacturers Association) low-pressure methods. Pressure washing roofs WILL void warranties; we never do that.

How long until the black streaks disappear?

The algae dies immediately on contact. Visible lightening shows within days; full clarity typically takes 1-2 weeks as rain and weather flush the dead growth off the shingles.

How often does a roof need this?

Every 2-4 years for most central Iowa roofs, depending on tree cover and exposure. Annual members get yearly inspections and treatment only when needed.

How much does roof soft washing cost in Des Moines?

Pricing depends on roof square footage, pitch, and algae severity. The ARMA-approved soft-wash method costs more than pressure washing — but pressure washing voids most shingle warranties and ages roofs prematurely. We quote in person after the inspection.

What about tile or metal roofs?

Soft washing works on both. Tile (less common in central Iowa) needs careful chemistry to avoid surface fading; metal is straightforward. We confirm the roof type during the in-person quote and adjust approach.

Will it damage my copper flashing or aluminum gutters?

Not when done right. Standard soft-wash solutions are safe for both. We pre-rinse all flashing and gutters before application and rinse again afterward. Improper chemistry left to dwell on metals can cause staining — we never let that happen.

Why not just pressure-wash the roof? It's cheaper.

Pressure washing a roof strips the granule layer that protects asphalt shingles from UV damage. Once the granules go, the shingles age 5x faster — a roof that should last 25 years can fail in 8–10 if it's been pressure-washed. The savings are eaten by replacing the roof early. Every major shingle manufacturer explicitly warns against pressure-washing.

What time of year is best?

Spring (April–May) and fall (September–October) are ideal — consistent temperatures, no flash-drying in heat, no freeze concerns. Summer roof soft-wash works but we schedule around the hottest days. Winter we don't soft-wash roofs in central Iowa.

— Roof Soft Wash · Polk County, IA

Roof Soft Wash in Ankeny.

Name: JBL Exterior Pros
Address: By appointment, Des Moines, IA, 50309, US
Telephone: (515) 619-0117
Price range: $$ – $$$
Rating: 5

Gentle algae removal that extends shingle life.

JBL Exterior Pros provides roof soft wash for homes across Ankeny, Iowa (50021, 50023, Polk County). JBL Exterior Pros uses ARMA-approved soft washing — low-pressure biocide application — that kills the growth without damaging granules or voiding manufacturer warranties. Results show within 1–2 weeks across central Iowa.

Result timeline: Visible in days, full clarity 1–2 weeks
Treatment cycle: Every 2–4 years typical
Standard: ARMA-approved, warranty-safe

— Why Ankeny homes need this

Roof Soft Wash, the Ankeny way.

Ankeny is the newest housing stock in our service area. Prairie Trail is a planned new-urbanist development with a mix of traditional and craftsman elevations on tight lots, all built 2005–present. Heritage and Otter Creek run more conventional suburban — 1990s–2010s production homes with vinyl siding, composite trim, and standard asphalt shingles. The east-side new construction is still ongoing as Ankeny pushes toward I-35 / NE 38th Street. Older Saylor Park stock is the closest thing Ankeny has to a historic neighborhood — mostly 1950s–70s ranch homes.

Because the housing stock is so young, hard-water staining on glass is rare and original interior windows tend to be in excellent shape. The work we see most in Ankeny is soft washing — vinyl siding on north-facing walls of 5–15-year-old homes is the most reliable algae-streak surface in our service area. Roof soft-wash starts to make sense on the earliest Prairie Trail homes now (built 2005–2008, north slopes are streaking). Prairie Trail has tight neighborhood association rules but exterior cleaning is universally permitted; gutters are sometimes routed in unusual ways for the architecture, which can mean longer downspout flush time.

— Plain English

Roof Soft Wash, in plain English.

Roof soft washing is the only safe method for cleaning algae, moss, and lichen growth from asphalt-shingle roofs. The black streaks visible on most American roofs aren't dirt — they're Gloeocapsa magma, an algae species that feeds on the limestone filler in asphalt shingles. Power washing would strip the granule layer that protects the shingles from UV degradation, voiding most manufacturer warranties and shortening roof life by years. Soft washing applies a low-pressure biocide that kills the algae at the root; rain and weather then carry the dead growth off the shingles over 1–3 weeks. ARMA (the Asphalt Roofing Manufacturers Association) certifies this method as warranty-safe.

— Local conditions

Central Iowa roof soft wash is its own thing.

Central Iowa's humid summers, mature tree canopy, and asphalt-shingle dominance create near-universal algae growth on north- and east-facing slopes. Roofs typically show first algae streaks within 5–7 years of installation, regardless of brand. Lichen — the green-grey patches — appears in the second decade, particularly in heavily-treed neighborhoods like Beaverdale, Drake, Sherman Hill, and older Urbandale. Moss shows in valleys and under tree drip-lines on the most shaded slopes. Most asphalt shingle warranties (Owens Corning, GAF, CertainTeed, Atlas) require ARMA-approved cleaning methods to remain valid. Iowa weather windows for roof soft-wash are spring (April–May) and fall (September–October); we don't soft-wash roofs in summer heat or winter freeze.

— Signs to call

When roof soft wash is overdue.

Black streaks running down north- or east-facing slopes
Green or grey patches (lichen) on shaded sections
Moss growth in roof valleys or under tree drip lines
Granule loss visible (dark staining where granules have washed off)
Insurance adjuster, HOA, or realtor noted roof condition
Approaching 3–5 years since last roof treatment
Adjacent neighbors recently re-roofed and you can now see the contrast

— How a visit goes

How a Ankeny roof soft wash visit goes.

01
Roof inspection and quote
We inspect from the ground and ladder — checking pitch, shingle condition, and growth severity. The written quote is precise to your roof.
02
Pre-rinse and soft-wash application
Landscaping gets pre-rinsed. We apply the biocide at low pressure across affected areas. It works on contact — most algae visibly lighten the same day.
03
Final rinse and confirmation
Roof and surroundings get a final rinse. Most full results show within 1-2 weeks as the dead growth weathers off.

— Spec sheet

What we use, what shapes the work.

Method: Low-pressure biocide application from ground or roof-edge — no walking on shingles unnecessarily
Cleaning solution: Sodium hypochlorite (2–4% for roof), surfactants, copper-based additive for moss
Pressure: 50–100 PSI (less than a garden hose) — chemistry does the work, pressure is irrelevant
Equipment: Long-pole low-pressure applicators, downstream injectors, harness for steep pitches
Standard: ARMA-approved methods only — never high-pressure, never scraping or brushing

— What to watch for

Roof Soft Wash mistakes other contractors make.

01
Power-washing the roof
The single worst thing a homeowner can do to an asphalt-shingle roof. High pressure strips the granule layer that protects the shingles from UV — once they're gone, the asphalt cures hard, cracks, and the roof fails years early. Every major shingle warranty explicitly excludes damage from pressure washing.
02
Walking the roof more than necessary
Asphalt shingles are softer in summer heat and brittle in winter cold. Excessive foot traffic on a roof — even by careful contractors — damages shingles. Our soft-wash technique applies biocide from the roof edge with long-pole equipment, walking only where access requires it.
03
Using the wrong chemistry near copper flashing or aluminum gutters
Strong sodium hypochlorite left to dwell on metals can cause staining or pitting. Proper soft-wash technique includes pre-rinsing flashing and gutters before application and rinsing again after — so chemistry never sits on metal long enough to react.
04
Single application without rinse plan
Some contractors apply the biocide and leave, expecting rain to handle the rinse. In central Iowa's variable summer weather, that can leave chemistry residue on the roof for days, eventually causing streaking. We rinse before we leave.
05
Cleaning in direct sun above 85°F
Hot shingles flash-dry the solution before it can work, leaving streaks and uneven results. We schedule roof work for cooler parts of the day, north-facing slopes in morning, south-facing in late afternoon — or reschedule entirely on extreme-heat days.

— Frequently Asked