black spots on the roof. can you tell me what is the cause of this? have lived in this house 12 years and have had no problems. what can you do to clean this?
This type of staining (algae as the other posters have said) will usually only happen on the North facing surface of the roof. Same with condensation on your car glass. Suprisingly, the North facing ... read more
There are two options available for reroofing installations. One would be to tear off the old roof before applying the new one (tear off). The second would be to lay new shingles over the existing roo ... read more