This is a good map to show where the problem areas are for roof algae growth in the United States.
The Very Serious and Serious areas are the parts of the country that have moisture and humity in the air. This moisture and humidity provides a great environment for the algae to live and thrive.
Algae loves moisture, that is why areas marked Minimal Problem are marked as such. They do not have the moisture content to sustain the algae and it's growth.
This is also the reason that you typically find roof algae growing on the northern or western facing surfaces of your house roof. These areas receive the least amount of sunlight, and stay damp longer.
Getting a roof cleaning will remove this destructive algae from your roof before it destroys your shingles and they need to be replaced before they shound need to be.
FOY
PROPERTY MAINTENENCE
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