How to Deal with Roof Moss and Algae Growth
Expert Roof Care by ASAP Roofing and Exteriors
Understanding the Threat: Moss and Algae on Your Roof
Moss and algae growth on your roof isn’t just unsightly—it’s a silent destroyer. These invaders retain moisture, damage shingles, and accelerate roof decay, especially in humid or shaded environments. Left unchecked, this growth can cut the life of your roofing system in half and even void your manufacturer’s warranty.
At ASAP Roofing and Exteriors, we’ve helped hundreds of Utah homeowners restore their roofs to a clean, damage-free condition—preserving their investment and boosting curb appeal.
Why Moss and Algae Grow on Roofs
Moss and algae thrive under very specific conditions:
- Shaded roof sections, especially under trees
- North-facing slopes with less sun exposure
- Excess debris like leaves and branches that trap moisture
- Humid climates or regions with frequent rain and morning dew
These conditions allow Gloeocapsa magma (the blue-green algae causing black streaks) and moss spores to colonize your roof. The result? A roof that looks neglected—and performs even worse.
The Hidden Damage They Cause
- Shingle decay – Moss lifts shingles, allowing water intrusion.
- Granule loss – Algae degrade asphalt granules, weakening shingles.
- Wood rot – Persistent moisture invites rot in decking and rafters.
- Ice dams – Moss impedes runoff, contributing to ice buildup in winter.
- Energy inefficiency – A darkened roof absorbs more heat, raising A/C costs.
That’s why ASAP Roofing and Exteriors takes a proactive approach to roof maintenance, targeting both the visible symptoms and root causes.
How ASAP Roofing and Exteriors Eliminates Moss and Algae Growth
We follow a professional multi-step process to fully clean and restore your roof without voiding warranties or damaging shingles.
1. Roof Inspection and Diagnosis
Every home is different. We begin with a comprehensive roof inspection, identifying high-risk areas and the type of biological growth present. Our team also checks for:
- Underlying moisture damage
- Lifted or deteriorating shingles
- Ventilation issues contributing to excess humidity
2. Safe, Eco-Friendly Roof Cleaning
We apply a non-pressure soft wash system that uses biodegradable cleaning agents to kill algae and moss without damaging your roof.
High-pressure washing can severely shorten your roof’s lifespan. Our gentle chemical treatments are safe for asphalt, tile, and metal roofing.
3. Manual Moss Removal (If Needed)
If moss has developed thick patches, we gently remove it by hand using specialized roofing tools, ensuring no granules are lost in the process.
4. Preventive Treatments
To keep your roof protected, we can install zinc or copper strips near the ridge. When it rains, these metals create an environment toxic to moss and algae—preventing regrowth for years.
Ongoing Maintenance: Your Best Defense
To avoid costly repairs and replacements, we recommend:
- Annual roof inspections by our certified team
- Regular gutter cleaning to ensure proper drainage
- Tree trimming to minimize shade and debris
- Installation of zinc strips on vulnerable roof areas
Let ASAP Roofing and Exteriors build you a roof care plan that prevents algae before it starts.
DIY Roof Moss and Algae Cleaning: What to Avoid
While DIY solutions may be tempting, most homeowners do more harm than good. Avoid:
- Bleach or harsh chemicals – These can corrode roofing materials and kill nearby landscaping.
- Power washing – This strips granules and voids warranties.
- Walking on the roof – Improper weight distribution leads to cracked or weakened shingles.
Call ASAP Roofing and Exteriors—we’ll treat and protect your roof safely, without putting your home or health at risk.
Frequently Asked Questions
How often should I clean moss off my roof?
We recommend treatment every 2–3 years, or annually in shaded, high-moisture areas.
Can moss really shorten my roof’s lifespan?
Yes. Moss traps moisture and degrades shingles, which accelerates roof aging and leads to leaks.
Does insurance cover moss-related damage?
Most homeowner policies do not cover damage from negligence or biological growth. Routine maintenance is key.
Will roof algae harm my family’s health?
Roof algae is not toxic, but mold spores from untreated growth can enter attics and contribute to air quality issues.
Customer Testimonials
“Our roof looked like a swamp—moss everywhere. ASAP Roofing and Exteriors cleaned it up in one afternoon. Looks brand new again!”
— Kelli T., Sandy, UT
“I thought I needed a new roof. These guys cleaned it and added zinc strips, now it drains better and hasn’t had moss return in 2 years.”
— Daniel P., Provo, UT
“The black streaks were ruining our curb appeal. ASAP Roofing came out, explained everything clearly, and had it spotless the same week.”
— Michelle R., Ogden, UT
Why Utah Homeowners Trust ASAP Roofing and Exteriors
We’re a locally owned and operated roofing contractor serving all of Utah, from St. George to Salt Lake City. We specialize in:
- Roof cleaning and restoration
- New roof installation and repair
- Gutter systems and drainage upgrades
- Winter weather prep and inspections
Ready to protect your roof and your home’s value? Contact ASAP Roofing and Exteriors today.