Los Angeles Roof Soft Washing Service
Dark streaks, black stains, and green patches on roofs in Los Angeles are almost always caused by algae (Gloeocapsa magma), moss, or lichen — not dirt. These organisms feed on limestone filler in asphalt shingles, gradually degrading them and shortening roof life. Soft washing — low-pressure cleaning combined with specialized biocidal solutions — kills these organisms at the root and restores the roof's appearance without the granule loss and shingle damage caused by high-pressure washing.
Roof soft washing in Los Angeles costs $250–$450 for a 1,500 sq ft roof and $350–$600 for a 2,500 sq ft roof. 30 of 30 verified providers in Los Angeles offer roof soft washing as a standalone service or bundled with house exterior cleaning. Service covers the Los Angeles metro area including Los Angeles County, Pasadena, Southern California. Never allow any provider to pressure wash an asphalt shingle roof — the Asphalt Roofing Manufacturers Association (ARMA) explicitly recommends against it. Only soft wash is appropriate.
After soft washing, treated algae and moss may not disappear immediately — biological material dies and washes away gradually over the next few weeks of rain. This is normal and expected. The roof will continue to lighten for 4–8 weeks following treatment. A second visit is rarely needed. Many Los Angeles homeowners schedule roof soft washing every 3–5 years or as soon as dark streaks reappear.
Los Angeles Providers Offering Roof soft washing
gutter cleaning · gutter repair · window washing · solar panel cleaning
gutter cleaning
gutter cleaning · window cleaning · sealing/staining after wash · solar panel cleaning
gutter cleaning · window cleaning · solar panel cleaning · auto detailing · paver sealing +2 more
gutter cleaning · downspout cleaning
window cleaning · fence cleaning · patio furniture cleaning
gutter cleaning · window cleaning · mold and mildew removal · moss removal
gutter cleaning · window cleaning · sealing/staining after wash · rust removal · solar panel cleaning +3 more
gutter cleaning · window cleaning · solar panel cleaning · bird proofing/bird control · algae removal +2 more
window cleaning · rust removal · graffiti removal
gutter cleaning · window cleaning · solar panel cleaning · roof cleaning · turf cleaning and sanitation
hydrocarbon removal · water treatment and recycling · environmental compliance consultation · toxic waste handling
bird proofing · bird dropping removal · solar panel maintenance
spiderweb removal
gutter cleaning · solar panel cleaning · bird proofing · Christmas light installation
gutter cleaning · oil and stain removal · graffiti removal
awning repair · water-repellant coating · UV protection coating · mildew removal · mold removal +2 more
concrete sealing · paver sealing · window washing · solar panel cleaning · drain cleaning +3 more
gutter brightening · sealing/staining after wash · solar panel cleaning · window cleaning
gutter cleaning · roof cleaning · concrete sealing · rust removal · mold removal +2 more
gutter cleaning · window cleaning · sealing/staining after wash · bird netting installation
gutter cleaning · solar panel washing
gutter cleaning · window cleaning · solar panel cleaning
solar panel cleaning
clay bar treatment · hand waxing · polishing · interior sanitizing
stain removal · efflorescence removal · restoration
gutter cleaning · solar panel cleaning · window cleaning
Roof Soft Washing FAQ — Los Angeles
How much does roof soft washing cost in Los Angeles?
Roof soft washing in Los Angeles costs $250–$450 for a 1,500 sq ft roof and $350–$600 for a 2,500 sq ft roof. Larger or steeper roofs run higher. Bundling with house exterior washing usually saves $50–$100. Compare quotes from 30 providers in Los Angeles for your specific roof size and pitch.
Is pressure washing safe for my roof in Los Angeles?
No — high-pressure washing on asphalt shingles strips protective granules, voids manufacturer warranties, and can force water under shingles causing leaks. The Asphalt Roofing Manufacturers Association (ARMA) recommends against pressure washing shingle roofs. Soft washing is the only appropriate method. If a Los Angeles company recommends pressure washing your shingle roof, it's a significant red flag.
What causes dark streaks on my roof in Los Angeles?
Dark streaks on Los Angeles roofs are almost always caused by Gloeocapsa magma — a blue-green algae that feeds on the limestone filler in asphalt shingles. Green patches are typically moss. Black or dark areas with texture are often lichen. All three are killed by soft washing solutions. Left untreated, they can significantly reduce shingle lifespan by degrading the granule layer.
How often should I have my roof soft washed in Los Angeles?
Most Los Angeles roofs benefit from soft washing every 3–5 years, or sooner if significant algae streaking appears. Homes in shaded, humid, or heavily treed areas may need cleaning every 2–3 years. After soft washing, results typically last 2–4 years before biological growth visibly returns. Some Los Angeles companies apply preventive zinc or copper strips after washing to slow regrowth.