Algae can be killed and the stains removed using chemical cleaners though they usually return over time.
How to remove roof stains.
Make your shingles last longer.
Do shingles on your north west or other shaded roofs have streaky moldy stains.
Next position your ladder against your home and make sure it s secure.
Black streaks on the north and west facing and shaded.
After that mix one part cleaner with six parts water in a pump sprayer.
Step 2 take safety precautions.
Allow the oxygen bleach to sit on the shingles for 20 minutes.
How to remove roof stains.
Since you ll be working with a bleach mixture make sure that any greenery in the vicinity is covered up to avoid.
Allow the bleach to remain on for 15 to 20 minutes then rinse it off with a hose.
Use a cleaner specially made for killing algae or by spraying a mixture of one part bleach to four parts water with tsp trisodium phosphate or other detergent added in a garden pump up sprayer.
Step 3 mix cleaning solution.
Cleaning the shingles first choose a non corrosive roof cleaner from your local home improvement store.
Step 1 cover foliage.
Here s how to clean the.
Use your garden hose to soak the affected area.
Step 4 apply solution.
Rinse from the top of the roof down to avoid re staining the shingles with the dirty water.