
Portions of ducts systems that pass through unconditioned space need to be better insulated than portions that pass through conditioned space. Unconditioned spaces include attics, crawl spaces, and other places in the home that are not fully insulated from outdoor temperatures. If ducts are not properly insulated, they can absorb or emit heat from these spaces, which causes the air traveling through your home to come out of different ducts at different temperatures. This is one of several causes of room-to-room temperature differences that homeowners experience and complain about. In addition, this loss of conditioning wastes energy and in some cases can result in water condensation.
