Hard to tell for sure without a close look, but the roofing / waterproofing material looks like TPO, a single-ply roofing membrance. It is not made for direct traffic, so appears someone has installe ... read more
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