Roof Cleaning & Soft Wash Services

Why Does North Texas Have Worse Roof Algae Than Most of the Country?

The DFW Metroplex sits in a humid subtropical climate zone with roughly 37 inches of annual rainfall and relative humidity that hovers between 60% and 80% even on 100°F summer afternoons. Those conditions are ideal for the cyanobacteria, moss, and lichen species that colonize asphalt shingles. North-facing roof slopes stay damp from dewfall well into late morning, which gives biological growth a multi-hour daily window to feed and reproduce. South-facing slopes bake under direct sun, which sounds protective but actually concentrates heat-tolerant algae strains and accelerates the bond between organic matter and the shingle surface.

Tree canopy is the second multiplier. Mature live oaks, cedar elms, and Eastern red cedars drop pollen, leaf litter, and small twigs into roof valleys every season, building a damp organic substrate that feeds growth between rain events. Older Fort Worth neighborhoods along the Trinity River corridor — Arlington Heights, Berkeley Place, Tanglewood, Mistletoe Heights, Westover Hills — have the densest tree cover and the highest rate of recurring algae complaints we see. Newer subdivisions in Haslet, Northlake, and Roanoke with younger landscaping see slower growth onset, but they catch up within 8 to 10 years as trees mature. If your neighbor's roof is streaked, your roof is the next host: spores travel on wind currents and reinfect adjacent properties season over season.

What Exactly Is Gloeocapsa Magma — and Why Does It Look Black?

The dark vertical streaks you see running from ridge to eave are not dirt, not mold, and not asphalt bleed. They are colonies of Gloeocapsa magma, a species of cyanobacteria (commonly called blue-green algae). Gloeocapsa is a photosynthetic organism that feeds on the limestone filler embedded in asphalt shingles, which is why algae growth is a shingle-specific problem and not a metal or tile problem. The "black" appearance is misleading — Gloeocapsa is actually a blue-green organism that produces a dark UV-protective pigment sheath as it matures. The pigment is the organism's sunscreen, and it is also what stains the shingle.

Gloeocapsa spreads by airborne spores released from existing colonies on tree canopies and neighboring roofs, which is why streaking often appears across entire DFW neighborhoods within the same year. It is important to distinguish algae from the two other common roof colonizers, because removal difficulty and damage profiles differ:

• Algae (Gloeocapsa magma): surface-level cyanobacteria, causes black streaking, easiest to remove, no physical penetration of the shingle mat.
• Moss (Bryophyta): a true plant with root-like rhizoids that penetrate between shingle granules. Holds moisture for days after rainfall and can lift shingle edges.
• Lichen: a symbiotic organism — fungus housing algae or cyanobacteria — that bonds to shingles with acid-secreting holdfasts. The most damaging and the hardest to fully remove.

What Does Moss Do to Shingles That Makes It More Serious Than Algae?

Moss is not a surface stain — it is a living plant whose rhizoids work their way between and underneath the shingle granules. The physical penetration is what makes moss more destructive than algae. Once a moss mat is established, it acts like a wet sponge sitting on top of your roof: shingles underneath stay damp for two to three days after a storm rather than drying within hours. Persistent moisture against the asphalt accelerates granule loss, encourages secondary fungal growth, and softens the asphalt mat itself.

In the rare North Texas freeze events — the February 2021 storm and the January 2024 cold snap — water trapped in moss mats freezes and expands, lifting shingle edges and sometimes tearing the corners. Even without freeze damage, long-term moss coverage will visibly accelerate granule shed: you will see brown sediment in your downspout splash blocks year-round. Both GAF and CertainTeed warranty documents identify "neglect" — including failure to remove moss and lichen — as a basis for warranty denial. If you let moss sit on a roof for five or more years, you have likely shortened the warranty-supported lifespan even before any visible shingle failure.

Why Is Lichen the Hardest Growth to Remove from a Roof?

Lichen is a composite organism — a fungus that hosts an algae or cyanobacteria partner — and it does not sit on the shingle, it bonds to it. Lichen produces acid-secreting holdfasts that etch into the granule-asphalt bond and physically anchor the colony to the roof. Pulling a mature lichen colony off a shingle by hand will typically take granules with it, which is why mechanical removal is not an option. The chemistry has to do the work, and the dwell time has to be long enough to kill the entire fungal-algal complex.

For a mature lichen colony — generally any visible patch wider than a half-dollar — a single soft wash treatment may visibly reduce the colony but not fully clear it. Realistic expectations: most lichen-heavy roofs require a second treatment 30 to 60 days after the first to clear the residual fungal anchor. We will tell you up front if your roof falls into this category and price the follow-up visit at a discounted rate. Algae-only roofs rinse clean in a single visit; lichen roofs are a different commitment.

Why Is Soft Wash the Only Method ARMA Approves for Asphalt Roofs?

The Asphalt Roofing Manufacturers Association (ARMA) Technical Bulletin on Algae Discoloration of Roofs is the industry reference document, and its position is unambiguous: the approved cleaning method for asphalt shingles is a low-pressure chemical application — never pressure washing. ARMA's stated concern is granule loss. The colored ceramic granules on the surface of your shingles are the protective layer that shields the underlying asphalt from UV, heat, and abrasion. Strip the granules and you have effectively shortened the roof's life.

A standard pressure washer outputs between 2,000 and 3,500 PSI. Soft wash, by contrast, runs at 40 to 60 PSI — about the pressure of a garden hose. The cleaning happens through chemistry, not mechanical force. GAF, CertainTeed, and Owens Corning — the three largest U.S. shingle manufacturers — all explicitly identify high-pressure cleaning as a warranty-voiding event in their installation and maintenance bulletins. Any contractor offering to "pressure wash" your roof at residential pressure-washer settings is offering to void your warranty. We will not do that work, and we will tell you so on the quote call.

What Cleaning Chemistry Does CARE Use on Roofs?

The active ingredient in ARMA-compliant roof cleaning is sodium hypochlorite (SH) — the same chemistry as household bleach, dilution-adjusted for application context. Stock SH from a chemical supplier is typically 10–12% concentration. We dilute it down to 3–6% for roof applications, which is the band that reliably kills algae, moss, and lichen at the cellular level without overloading the rinse-runoff zone. Too weak a mix means incomplete kill and faster regrowth; too strong means unnecessary load on landscaping and gutters.

We add a roof-grade surfactant to the mix to do two things: increase the dwell time of the chemistry on the shingle (so it actually penetrates lichen holdfasts and moss mats) and reduce immediate runoff during application. Plant protection is built into our process: we pre-wet every planting bed and tree within the splash zone before any chemistry hits the roof, install downspout covers to capture concentrated runoff, and post-rinse all vegetation thoroughly when the application is complete. We ask homeowners to water their landscaping the morning of the visit as a redundant safeguard. Done correctly, soft wash leaves the roof clean and the landscaping untouched. Done sloppily, it scorches azaleas and burns turf — which is why dilution calibration and rinse discipline are not optional.

What Roof Types Does CARE Clean?

Different roofing materials require different chemistry, different concentrations, and different application techniques. Here is what we clean and what we don't:

Asphalt Shingles (3-Tab and Architectural)

The primary roof cleaning application in North Texas. ARMA standards apply: low-pressure soft wash with diluted SH and surfactant. Architectural (dimensional) shingles hold algae longer than 3-tab because their stepped profile creates more shaded micro-environments. Both clean equally well with proper dwell time.

Metal Roofing (Standing Seam, Corrugated, Stone-Coated Steel)

Metal panels do not host the limestone-feeding algae that asphalt does, so the issue is usually surface oxidation, organic debris, and lichen on stone-coated steel. We use a lower SH concentration on metal and a different surfactant to avoid streaking the finish, with no acid-based chemistry that could compromise galvanization or factory paint.

Clay and Concrete Tile

Tile is the most porous roofing surface, which means lichen and moss are the most common colonizers — algae streaking is rarer. Zero pressure on tile: walking the field is also restricted to felt pads and structural high points to avoid cracking. Chemistry-only application, longer dwell time, and a careful rinse from above.

Cedar Shake

Cedar shake develops a combination of UV oxidation, biological growth, and embedded debris. We use specialized biodegradable chemistry calibrated for wood and inspect every job for rot before accepting it. If a cedar roof is structurally compromised, we will refuse the cleaning and refer you to a roofer — soft wash on rotted cedar is not a fix, it is a cosmetic delay.

What CARE Does NOT Clean

We decline slate roofs (too brittle — slates chip under any pressure or even foot traffic), flat TPO/EPDM commercial membrane roofs (see our commercial pressure washing page for those jobs), and modified bitumen flat roofs. If you call us about one of these, we will tell you up front and refer you to a specialist rather than take the job.

What Are the Warning Signs Your Roof Needs Cleaning?

Most homeowners notice the problem only once the streaking is severe enough to be visible from the curb. A trained eye catches it earlier. Watch for:

• Dark vertical streaks running ridge-to-eave — the classic Gloeocapsa magma signature, usually appearing first on the north slope.
• Green or fuzzy patches in roof valleys and shaded sections — early-stage moss colonies, often where leaf debris collects.
• Black mottling on south-facing slopes — heat-concentrated algae, often appearing as a uniform dark band rather than streaks.
• Visible moss tufts or gray-white lichen patches — established colonies, indicate growth has been present for 2+ years.
• Recurring staining within 12–24 months of last cleaning — signals an active reinfection source (overhanging tree canopy, neighbor's untreated roof).
• HOA citation letter or insurance reinspection notice — a fixed remediation window starts the moment that letter is dated.
• Granule sediment in gutter beds and downspout splash blocks — early shingle degradation, accelerated by biological growth.

How Do You Know Whether Your Roof Needs Cleaning or Replacement?

Cleaning a roof that should be replaced is wasted money. Replacing a roof that just needs cleaning is wasted thousands. The diagnostic line runs through three checks:

Granule loss assessment. Walk to your downspouts and look at the splash blocks and gutter beds. A light dusting of granules is normal — heavy sediment with visible bare spots on shingles when viewed from the ground is not. If the gutter beds are full of granules and the south-facing slope looks patchy from below, get a roofer's opinion before you pay for cleaning.

Curling vs. staining. Curled, cupped, or lifted shingle edges are a structural problem that cleaning cannot reverse. Staining without curling is a biological problem that cleaning fixes completely. If your shingles are flat but stained, you have a cleaning candidate. If they are curling, you have a replacement candidate — regardless of how the surface looks.

Roof age. Most asphalt shingles are warranted 25 to 30 years but functionally last 18 to 22 years in North Texas heat. Under 10 years with growth: clean, you are protecting a long-life asset. 10 to 18 years with growth and no curling: clean, you are extending remaining life. 20+ years with growth plus curling or lifting: get a roofer's assessment before spending on cleaning. The cost gap is consequential — a roof clean in Fort Worth runs $299 to $599, while a full replacement on an average-sized home runs $12,000 to $18,000+. We will tell you on the quote call if we see signs that suggest a roofer should look first.

How Long Does a Roof Cleaning Take?

A single-story home is typically a 2-to-3 hour visit, including setup, application, rinse, and walkthrough. A two-story home runs 3 to 5 hours. Several factors push the upper end of those ranges:

• Roof pitch above 8/12. Steep pitches require harness and rope work, which slows the application without changing the cleaning result.
• Heavy tree canopy. Significant leaf debris in valleys and on flat sections requires pre-cleaning before chemistry applies cleanly.
• Lichen severity. Lichen needs longer dwell time and sometimes a sectional re-application, which extends total visit length.
• Skylight and solar panel proximity. Each obstacle requires a measured workaround rather than a continuous spray pattern.

One important detail to set expectations: your roof keeps improving after we leave. Black algae streaks rinse off during the visit, but moss mats and lichen colonies continue to die back and weather away over the following 2 to 4 weeks of normal rainfall. The roof you see at the end of our walkthrough is not the final result — it is the starting point of a 30-day rinse-off period.

How Should You Prepare Your Home for Roof Cleaning?

Five steps from the homeowner make the visit faster and lower-risk:

1. Close all windows and doors before we arrive — including attic vents you can access. Soft wash droplets travel further than people expect.
2. Move outdoor furniture, grills, and decorative items at least 6 feet from the home perimeter, or under cover. Cushions and fabrics in particular should be relocated.
3. Water all landscaping and garden beds thoroughly the morning of the visit. Pre-saturated plants are far less susceptible to chemistry contact.
4. Tell us at booking about solar panels, skylights, attic fans, and exterior outlets — each has a specific precaution we plan for in advance, not on arrival.
5. Remove bird feeders and hummingbird feeders for the day. SH chemistry is harmful to birds; we want them away from the splash zone during the application window.

If you have cracked or loose gutters, mention them at the quote call. Soft wash rinse volume is low compared to pressure washing, but a structurally compromised gutter run can fail under any added water weight.

How Often Should You Clean Your Roof in North Texas?

The general guideline is every 2 to 4 years, with frequency driven by shade, tree proximity, and HOA or insurance pressure. Specifics:

• Heavily shaded roofs — north slopes, lots under live oaks or cedar elms — every 2 years.
• Mixed sun-shade roofs — typical for Keller, Southlake, Trophy Club homes — every 3 years.
• Open-exposure roofs with full sun and no significant tree canopy — every 4 years is usually enough.

Insurance is increasingly forcing the timeline. Several DFW carriers — State Farm and Allstate among them — have begun issuing reinspection notices that require visible roof cleaning as a condition of policy renewal. If you receive a notice citing roof condition, you typically have 30 to 60 days to remediate. HOA enforcement is the other accelerant: Southlake, Trophy Club, and Colleyville boards are now actively citing visible streaking and lichen on dues-paying members. A formal citation triggers a fixed remediation window with fines beyond it.

Waiting longer than the recommended window costs more, not less. A 2-year algae cleaning is a single-visit job. A 5-year lichen cleaning may require two visits and 50% more chemistry. The compound interest works against you.

What Does Roof Cleaning Cost in Fort Worth?

Pricing is driven by roof surface area, pitch, growth severity, and any bundled services. Here is the working breakdown:

• Single-story homes: starting at $299 — includes full soft wash, valley cleaning, and post-job walkthrough.
• Two-story homes: $399 to $599 — depending on size and access.
• Steep-pitch surcharge: +$50 to +$100 for pitches above 8/12 due to harness work and slower application.
• Lichen severity adjustment — lichen-heavy roofs requiring extended dwell time or second-visit pricing are quoted explicitly, not surprise-billed.
• Square footage matters more than home footprint — a one-story sprawl can have more roof than a two-story compact home.
• Bundled gutter clean discount — adding gutter cleaning to a roof visit is significantly cheaper than booking it standalone, since the tech is already on the roof.
• No travel surcharge within the 19-city service area — Fort Worth, Keller, Southlake, and the surrounding cities all price the same.
• Free quote includes a roof condition note — visible damage, flashing issues, valley concerns — at no charge whether you book the cleaning or not.

For a complete flat-rate pricing breakdown across all services, our pricing page lists roof cleaning, house washing, gutter cleaning, and bundled discounts in one place.

Can You Combine Roof Cleaning with Gutter Cleaning or House Washing?

Bundling is the most cost-effective way to use a single CARE visit. Two combinations dominate the booking sheet:

Roof + gutter cleaning. The technician is already on the roof or the ladder. Adding gutter clean-out and flush takes minimal additional time and the bundled rate reflects that. This is the most common pairing — about 6 of every 10 roof cleaning bookings add gutters.

Roof + house washing. The sequencing matters: house wash first, roof clean second, or roof clean with the rinse fully captured. Soft wash rinse running off a freshly cleaned roof down freshly cleaned siding will not stain a clean exterior, but the reverse — rinse from a dirty roof onto clean siding — re-deposits algae residue. Most homeowners book soft-wash siding cleaning together with the roof for a full exterior reset.

The full-package combination — roof, gutters, house wash, and driveway — is also offered as a single-visit reset. Roof and gutters typically run a morning; house wash and driveway can fit the same day or be split across a return visit, depending on weather and crew scheduling. All four services fall under our soft-wash and pressure washing services.

What Cities Does CARE Serve for Roof Cleaning?

CARE provides roof cleaning and soft wash across 19 cities in Tarrant and Denton counties: Fort Worth, Keller, Southlake, Trophy Club, North Richland Hills, Grapevine, Colleyville, Hurst, Euless, Bedford, Haltom City, Watauga, Roanoke, Northlake, Haslet, Argyle, Flower Mound, Lake Worth, and Saginaw. There is no travel surcharge anywhere in the service area — a roof clean in Saginaw is priced the same as a roof clean in our home Fort Worth service area. Same crew, same equipment, same pricing. If you are outside this 19-city footprint and still want a quote, call us — we occasionally accept jobs in adjacent cities like Mansfield, Burleson, or Justin when crew routing allows.