The use of air barriers in buildings is a relatively new activity in the United States. Air barrier requirements were included in energy codes in 2006 and are proposed to the IRC/IBC to deal with moisture. Design professionals, contractors and installers are acquiring the expertise for the proper installation of air and water-restive barriers. There has been a lot of discussion on how tight a building should be, how effective air barriers are, and what the energy savings will be when an air barrier is used in the building envelope.
For years, the U.S. Department of Energy advised consumers that 30 to 40 percent of the energy used in a building was due to air leaking in and out of a building. People generally accepted that air leakage did result in heat loss and that the gaps and cracks needed to be sealed to provide comfort for the occupants.