Roof Cleaner Concentrate
DEFY® Roof Cleaning Products for Removing Black Algae Stains
The most common culprit causing the black streaks on roofs is a blue-green algae called Gloeocapsa magma. Over the past 25 years this strain of algae has become more hardy and has migrated to less humid environments.
It has now become a common sight on asphalt roofs across 80% of the United States. This unsightly growth usually occurs on the north or west side as well as shaded areas of the roof.
As the algae grows and decomposes, it holds moisture, which accelerates its growth.
Safe and Not-So-Safe Roof Cleaning Products
DEFY® Roof Cleaner is a fast, effective product for roof shingle cleaning and is the safest way to clean and restore the appearance of your roof. One gallon of roof cleaner concentrate makes 7 gallons and will cover 700-900 square feet, depending on severity of stains and roof texture. Using roofing cleaning products like chlorine bleach or sodium hydroxide will accelerate corrosion of metal gutters, downspouts, flashings, and roofing fasteners. Sodium hydroxide is the active ingredient found in many paint strippers, oven cleaners and drain cleaners. It is caustic and high concentrations may cause irreversible damage to asphalt shingle roofs.
Besides the obvious health risks of handling sodium hydroxide and chlorine bleaches, strong bleach solutions will damage almost any hard surface that comes in contact with it. Asphalt shingles are no exception.
DEFY® Roof Cleaner is the first effective roofing cleaning product that does not rely on harsh chemicals like chlorine bleach or sodium hydroxide.
It strikes a perfect balance between aggressive cleaning and not being harmful to the roof or surrounding vegetation. It’s made of an optimized blend of detergents, coupled with a unique buffered Sodium Metasilicate – a chemical made from sand and soda ash, which is recognized as a non-pollutant. For severe stains, especially on lighter colored roofs, multiple applications may be required. In some cases, complete stain removal may not be possible.
DEFY® Roof Cleaner is the first step in a 2 step system to clean and protect your roof. To find out more about the roof cleaning tools needed, go to our Roof Cleaning Tools page. Once your roof is clean, the next step is to block the black roof stains from coming back with DEFY® Stain Blocker for Roofs.
For more details on our roof cleaning system, read our report on Asphalt Roof Cleaning and Stain Prevention.
Product Data
- Available Sizes: 1 gallon concentrate
- Coverage Rate: 700 - 900 total sq. ft. per concentrated gallon when diluted 6:1. Each gallon of concentrate makes 7 gallons
- Application Method: Roof Cleaner Applicator
- Rinsing Method: Roof Rinsing Tool (80 psi recommended)
- Cleanup: Soap and water
Roof Cleaning Steps
Step 1: Clean
Wet the section of the roof down that you will be working on first. Apply the Roof Cleaner Concentrate using the Roof Cleaner Applicator tool. Spray this on the roof and allow it to set for 15 minutes. (Make sure it remains wet. If it dries out, spray more cleaner or some water on it to keep the cleaner active)
Step 2: Rinse
After attaching the Roof Rinsing Tool to the end of your hose, turn on the water, then turn on the utility water pump. Start at the peak of the roof and work your way down towards the gutters, rinsing the Roof Cleaner Concentrate off the roof.
Step 3: Block
After the entire roof has been cleaned and rinsed, apply the Stain Blocker for Roofs using a pump sprayer. This can be applied to a damp roof, and does not need to be rinsed off.