Those Dark Streaks Are More Than Ugly
You have seen them. Dark black or greenish streaks running down your roof, usually starting on the north-facing slopes where moisture lingers longest. Maybe you have noticed them getting worse each year, creeping a little further across the shingles every season. You might have assumed they are just dirt or normal aging, something you have to live with until it is time to replace the roof.
Here is what those streaks actually are: a type of algae called Gloeocapsa magma. It feeds on the limestone filler in asphalt shingles, and it is literally eating your roof. Left unchecked, it shortens the lifespan of your shingles, reduces your home's energy efficiency by darkening the roof surface, and makes your entire home look neglected. In Green Bay, where lake effect moisture and humid summers create ideal growing conditions, roof algae is an extremely common problem.
Moss is another frequent issue, especially on shaded roof sections. Unlike algae, moss has a root system that works its way under shingle edges, lifting them and creating entry points for water. During Wisconsin's freeze-thaw cycles, that trapped water expands and contracts, accelerating damage with every temperature swing.
Your first instinct might be to get up there with a pressure washer and blast it all off. This is one of the worst things you can do to a roof. High-pressure water strips the protective granules from asphalt shingles, voids most manufacturer warranties, and can force water under the shingles and into your home. It turns a cosmetic problem into a structural one.
Why Soft Washing Is the Right Approach
Soft washing is fundamentally different from pressure washing. Instead of relying on high-pressure water to physically remove contaminants, soft washing uses specialized biodegradable cleaning solutions applied at very low pressure, no more force than a garden hose. The cleaning solution does the work, not the water pressure.
Our roof-safe cleaning solutions kill algae, moss, lichen, and mildew at the cellular level. This means the organisms are not just knocked off the surface where they can quickly regrow. They are eliminated entirely. The result lasts significantly longer than a high-pressure blast, and your shingles are left completely intact with all their protective granules in place.
The Asphalt Roofing Manufacturers Association (ARMA) specifically recommends soft washing as the only approved method for cleaning asphalt shingle roofs. Using high pressure can void your shingle warranty and your homeowner's insurance coverage for roof damage.
What We Remove from Your Roof
- Black streaks caused by Gloeocapsa magma algae
- Green algae and biological growth
- Moss and its root systems
- Lichen colonies
- Mildew and fungal growth
- Accumulated dirt and debris
Our Roof Soft Washing Process
1. Roof Inspection
We examine your roof from the ground and, when safe to do so, up close. We identify the types of growth present, assess the condition of your shingles, and note any areas that need special attention or repair.
2. Property Protection
Before we apply any cleaning solution, we thoroughly wet and protect your landscaping, cover sensitive outdoor items, and ensure that runoff is managed properly. Our solutions are biodegradable, but we take every precaution to protect your plants and property.
3. Soft Wash Application
We apply our cleaning solution evenly across the roof surface using low-pressure spray equipment. The solution begins working immediately, breaking down algae, moss, and other organisms on contact. Dwell time varies based on the severity of growth.
4. Gentle Rinse and Review
We rinse the roof with low-pressure water, removing the cleaning solution and dead organic material. Most results are visible immediately, though some heavily stained areas may continue to improve over the following days as rain naturally rinses away remaining residue.
Benefits of Professional Roof Cleaning
Extended Roof Life
Removing algae and moss stops them from degrading your shingles. Regular cleaning can add years to your roof's lifespan, delaying the significant expense of a full roof replacement.
Lower Energy Bills
Algae-darkened roofs absorb more heat, forcing your air conditioning to work harder in summer. A clean roof reflects sunlight more effectively and helps keep your home cooler.
Warranty Protection
Our soft wash method is the only cleaning approach recommended by shingle manufacturers. We clean your roof without voiding your warranty or your insurance coverage.
Protect Your Roof Today
Your roof is one of the most expensive components of your home. Do not let algae and moss shorten its lifespan when a professional soft wash can eliminate the problem safely and affordably. Contact Green Bay Pressure Washer for a free roof inspection and estimate.