a building insulation system for roofs and walls supported from the interior side of the building , which eliminates thermal bridges and bottom side ceiling fasteners to support the insulation system materials during the insulation and exterior sheeting process of the building construction . the insulation system creates an air gap space layer in roofs and in walls between the exterior wall and roof sheeting panels and the interior sheet material , which supports the insulation material layer . an air gap space enables active solar energy collection and its use to reduce the overall purchased energy for operation of the building . the insulation system preferably includes a support sheet material , a sheet material tensioning devices , an insulation material layer , insulation hanger retention devices , heat and air collection and distribution ducts , dampers , louvers , pipes , dehumidification and condensate collection devices used in the air gap layers of the building to improve the building energy efficiency .