Since 1994, the International Codes, or I-Codes, have served as models for almost all state and local codes in the United States. The 2012 edition of the I-Codes includes several landmark advances to increase energy efficiency in buildings. Not only does the 2012International Energy Conservation Code (IECC) include new and higher standards for almost every component in the building envelope,but these standards are further increased in the new International Green Construction Code (IgCC), which is intended to serve as anoverlay code, or #above the code# standard for sustainable buildings.