Commercial Building Energy Codes establish a minimum level of energy efficiency for commercial buildings. Generally, codes specify requirements for "thermal resistance" of the building shell and windows, and minimum heating and cooling equipment efficiencies. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards introduced before 1999 do not meet the requirements of the federal Energy Conservation and Production Act (ECPA).
Updated: June 3rd, 2009