Allow the bleach to remain on for 15 to 20 minutes then rinse it off with a hose.
Roof discoloration cleaning.
They re likely to damage the shingles.
How to clean roof stains wash your shingles where the sun doesn t shine.
Tiles are also very fragile and can crack easily under pressure.
Do shingles on your north west or other shaded roofs have streaky moldy stains.
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.
Other cleaning chemicals or methods should not be used without approval of the shingle manufacturer.
Roof cleaning in such abrasive ways makes it necessary to re coat the seal and paint to protect the roof from dirt and moss infestation.
To keep your roof safe and sightly choose a cool overcast day mix a cleaning solution spray it onto your roof then rinse after 20 minutes.
A typical solution should be one part chlorine bleach and one part water.
The less expensive solution is to spray wash the roof with a 50 percent mix of water and bleach to get rid of the algae.
Black streaks on the north and west facing and shaded.
Part 1 making preparations for chemical cleaning.
Algae can be killed and the stains removed using chemical cleaners though they usually return over time.
Make your shingles last longer.
Avoid using such measures when possible.
Here s how to clean the.
Some of this growth including the stains from algae spores are cosmetic but others such as moss cause costly damage to your roof.