Preventing Roof Algae & Black Streaks on Commercial Buildings: Why Professional Roof Washing Matters
Introduction: The Overlooked Top of Your Building
When business owners think of property maintenance, they usually focus on the ground level — storefronts, sidewalks, parking lots, and windows. But there’s one area that often gets overlooked: the roof.
Commercial roofs are massive investments, and yet many facilities allow them to become discolored by black streaks, algae, moss, and lichen. In addition to looking unprofessional, these growths can shorten the life of your roof, increase energy bills, and even damage structural integrity.
For businesses in Northeast Indiana and Northwest Ohio, where humidity and seasonal weather fluctuations are common, roof washing is not just cosmetic — it’s preventative maintenance.
What Are Those Black Streaks?
The dark streaks you see on commercial roofing aren’t just dirt. They’re usually caused by Gloeocapsa magma, a type of algae that thrives in humid climates. This airborne organism travels from building to building and feeds on the limestone filler found in many asphalt shingles.
Other roof invaders include:
Moss – Retains moisture, accelerating shingle deterioration.
Lichen – Creates root-like anchors that penetrate roofing surfaces.
Mold & mildew – Discolor surfaces and increase water retention.
These organisms don’t just stain roofs; they actively damage them.
Why Dirty Roofs Hurt Businesses
A stained, streaky roof creates problems far beyond looks.
Poor First Impressions
Customers, tenants, and clients notice roofs — especially on larger buildings. Black streaks and green growths give the impression of neglect, which can affect how people view your business.Reduced Roof Lifespan
Algae and moss feed on roofing materials. Over time, they loosen shingles or create cracks in flat-roof membranes. Left untreated, you may face early roof replacement.Higher Energy Bills
Black streaks absorb more heat. This increases indoor cooling costs, especially in summer, making dirty roofs an ongoing drain on your operating budget.Potential Liability
Heavy moss and lichen hold water, adding weight and moisture damage to roofing structures. In extreme cases, this can lead to leaks or unsafe conditions.
The Financial Cost of Ignoring Roof Cleaning
Replacing a commercial roof is one of the most expensive building repairs a business can face. Depending on size and materials, costs can range from tens of thousands to hundreds of thousands of dollars.
Routine roof washing prevents premature replacement and provides a massive return on investment. For a fraction of replacement costs, regular maintenance preserves your roof for years longer while keeping your building looking sharp.
How Roof Washing Works
Professional roof washing is a specialized process. Unlike sidewalks or parking lots, roofs require low-pressure techniques to avoid damage.
At TLC: Making It Easy, our roof washing process includes:
Inspection – Identifying algae, moss, and lichen growth.
Soft washing – A low-pressure method combined with safe cleaning solutions that remove organic growth without damaging roofing materials.
Rinse & protection – Ensures black streaks and algae are gone while reducing the chance of fast regrowth.
This approach not only restores the roof’s appearance but also safeguards its long-term performance.
Industries That Benefit Most From Roof Washing
While every commercial building can benefit, some industries see the biggest advantages:
Retail stores & shopping centers – Roof visibility from parking lots means streaks are always noticed.
Healthcare facilities – Patients expect cleanliness and care in every aspect of the property.
Restaurants – Outdoor diners or drive-thru customers notice rooflines up close.
Schools & universities – Roof longevity is essential for large, high-use facilities.
Auto dealerships – Large roofs and clean branding demand spotless appearances.
For these industries, roof washing isn’t optional — it’s an essential part of facility management.
How Often Should Commercial Roofs Be Washed?
The frequency depends on building type, location, and roofing material:
Every 2–3 years – Standard schedule for most commercial roofs.
More often if – Building is surrounded by trees, in high-humidity areas, or has visible algae growth.
Immediate attention if – Black streaks or moss are already visible.
The earlier algae and streaks are treated, the less damage occurs and the easier the wash.
Why Professional Roof Washing Is Essential
Roof cleaning is not a DIY project. Attempting to pressure wash or scrub a roof without experience can cause:
Shingle damage
Membrane tearing
Voided manufacturer warranties
Safety hazards for staff or untrained workers
Professional crews have the right equipment, cleaning solutions, and safety procedures to clean roofs effectively without causing damage.
The TLC Advantage in Roof Washing
At TLC: Making It Easy, we bring commercial clients a proven system for roof care:
Soft washing technology – No high-pressure damage.
Algae and streak removal – Restores roofing to a like-new appearance.
Preventative maintenance plans – Customized schedules for your facility.
Local expertise – We understand the unique weather and humidity patterns of Indiana and Ohio.
Our teams have experience cleaning roofs on everything from single-story restaurants to large office complexes, ensuring safe, professional results every time.
Case Example: Office Building in Fort Wayne
A property manager in Fort Wayne noticed black streaks covering much of their office building roof. Tenants were complaining about the building’s neglected appearance, and the manager worried about long-term damage.
We performed a soft wash roof cleaning, removing algae and streaks across the entire structure. Afterward, the roof looked years newer, and tenants immediately noticed the difference. The property manager reported increased tenant satisfaction and lower complaints about building upkeep.
Long-Term ROI of Roof Washing
When comparing the cost of routine roof washing versus neglect, the numbers are clear:
Without cleaning: Roof replacement costs can reach six figures.
With cleaning: Routine maintenance every 2–3 years keeps roofs in good condition, extending their lifespan significantly.
Additionally, the energy savings from removing heat-trapping black streaks can reduce operating costs month after month.
Conclusion: Protect Your Roof, Protect Your Business
Your roof may be out of sight, but it should never be out of mind. Black streaks and algae growth aren’t just ugly — they’re signs of damage that can shorten your roof’s life, increase bills, and undermine your professional image.
✅ The bottom line: Routine roof washing is one of the smartest investments a commercial property can make.