Opaque Envelope for Building Code Officials

The Opaque Envelope includes all the elements of a building that separate heated or cooled space from exterior space. The energy code includes requirements for walls, floors, and ceilings, as well as for slab foundation edges. These requirements promote thermal effi-ciency in constructing the building envelope. A poorly insulated build-ing envelope wastes significant amounts of energy and prevents the building components from working together as an integrated system. Without a tight, well insulated building envelope, many other energy efficient measures will not function effectively.