How to Remove Black Streaks from Your Roof in Georgetown TX
If you have noticed dark black or gray streaks running down your roof in Georgetown TX, you are not alone. This is one of the most common exterior cleaning issues in Central Texas — and it is caused by a specific organism that thrives in Georgetown’s warm, humid climate. This guide explains what causes black roof streaks, why they are a problem, and how Georgetown Texas Power Wash safely removes them using the ARMA-recommended soft wash method.
What Causes Black Streaks on Georgetown TX Roofs?
The black streaks on Georgetown roofs are caused by Gloeocapsa Magma — a cyanobacteria (blue-green algae) that feeds on the limestone filler in asphalt shingles. Georgetown’s warm summers, high humidity, and limestone-rich environment create ideal conditions for this organism to thrive and spread.
Gloeocapsa Magma spreads from roof to roof via wind and birds. Once established, it creates the characteristic dark streaks that run from the ridge down to the eaves. Left untreated, it degrades shingles, reduces reflectivity (increasing cooling costs), and can void manufacturer warranties.
Why High-Pressure Washing Is NOT the Answer
Many Georgetown homeowners make the mistake of hiring a pressure washing company that uses high-pressure washing on their roof. This approach:
- Strips granules from asphalt shingles, reducing their protective coating
- Accelerates shingle wear and reduces roof lifespan
- Can void manufacturer warranties
- Does NOT kill Gloeocapsa Magma at the root — streaks return within months
- Can force water under shingles, causing leaks and water damage
The ARMA-Recommended Soft Wash Method
The Asphalt Roofing Manufacturers Association (ARMA) recommends soft washing as the only safe method for cleaning asphalt shingle roofs. Georgetown Texas Power Wash uses this method exclusively:
- Pre-treatment — Apply biodegradable cleaning solution to the entire roof surface
- Dwell time — Allow solution to penetrate and kill Gloeocapsa Magma at the root
- Low-pressure rinse — Gentle rinse to remove dead organism and cleaning solution residue
- Post-treatment inhibitor — Apply inhibitor to slow regrowth and extend cleaning results
How Long Does Roof Cleaning Last in Georgetown TX?
A professional soft wash roof cleaning by Georgetown Texas Power Wash typically keeps roofs clean for 2–4 years in Georgetown’s climate. Our post-treatment inhibitor application extends results significantly compared to cleaning without inhibitor.
Roof Cleaning Cost in Georgetown TX
The roof cleaning cost in Georgetown TX typically ranges from $300 to $700 for a standard residential roof. Georgetown Texas Power Wash provides free, written estimates for every roof cleaning job. Call (512) 661-6944.
Frequently Asked Questions
What are the black streaks on my Georgetown TX roof?
The black streaks on Georgetown TX roofs are caused by Gloeocapsa Magma — a cyanobacteria that feeds on limestone filler in asphalt shingles. Georgetown Texas Power Wash removes it using the ARMA-recommended soft wash method.
Will the black streaks come back after cleaning?
With Georgetown Texas Power Wash’s post-treatment inhibitor application, results typically last 2–4 years. Without inhibitor, streaks may return within 12–18 months.
Is roof cleaning covered by homeowner’s insurance?
Some homeowner’s insurance policies cover roof cleaning if the growth is causing damage. Check with your insurance provider. Georgetown Texas Power Wash can provide documentation of the cleaning for insurance purposes.
Call (512) 661-6944 for a free roof cleaning estimate. Georgetown Texas Power Wash — #1 pressure washing company in Georgetown, TX.