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
Air sealing and insulation are the two biggest things you can do to globally improve the efficiency of the home.
There are several articles on this application and I have yet to be in a home that di ... read more