The Illinois Energy Conservation Code requires design and construction professionals to follow the latest published edition of the International Energy Conservation Code (IECC) and the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 90.1 “Energy Standard for Buildings except Low-Rise Residential Buildings” including amendments adopted by the Capital Development Board.

State Funded Facilities must comply with ASHRAE 90.1 per 20 ILCS 3105/10.09-5. See Subpart B of the Illinois Energy Conservation Code for more information.The 2010 edition of ASHRAE 90.1 went into effect on 1/11/13.

Privately Funded Commercial Facilities must comply with IECC per 20 ILCS 3125.See Subpart C of the Illinois Energy Conservation Code for more information. The 2012 edition of the IECC went into effect on 1/11/13.

Residential Buildings must comply with IECC per 20 ILCS 3125. See Subpart D of the Illinois Energy Conservation Code for more information. The 2012 edition of the IECC went into effect on 1/11/13.

Comment Period for Amending the Illinois Energy Conservation Code

The Capital Development Board (CDB), in conjunction with the Department of Commerce and Economic Opportunity, is beginning the update cycle for the Illinois Energy Conservation Code from the 2012 International Energy Conservation Code (IECC) to the 2015 IECC.   Proposed amendments will be accepted by the Illinois Energy Conservation Advisory Committee from July 1, 2014 - December 1, 2014.  For more information click here