Step 1. Know the Requirements

Current national model energy codes and standards are limited to the design and construction of buildings. That is, the operation and maintenance of the building, however important that might be to the overall energy usage of the building, is not considered in current national model energy codes and standards.1

This toolkit is focused on the codes and standards called out in the American Recovery and Reinvestment Act of 2009 (ARRA), but most of the principles apply to any code.

For the residential build community, ARRA requires states to meet or exceed the 2009 International Energy Conservation Code (IECC) or achieve equivalent or greater energy savings. For the commercial build community, states must meet or exceed ANSI/ASHRAE/IESNA Standard 90.1-2007 (ASHRAE Standard 90.1-2007) or achieve equivalent or greater energy savings to qualify to receive federal funding. Many adopting authorities do not adopt ASHRAE Standard 90.1 directly but instead adopt the IECC. The 2009 IECC contains two options for commercial buildings: (1) ASHRAE Standard 90.1-2007 by reference, or (2) a set of requirements directly in the IECC. The commercial requirements in ASHRAE Standard 90.1-2007 and the 2009 IECC are similar but not identical. This toolkit will discuss some of those differences.

Both ASHRAE Standard 90.1-2007 and the 2009 IECC have been superseded by newer versions that require higher levels of energy efficiency. ASHRAE Standard 90.1-2010 was published in August of 2010 and the 2012 IECC was published in May of 2011. This toolkit also addresses enforcement issues that may arise in ASHRAE Standard 90.1-2010 and the 2012 IECC. The first step in effective enforcement of energy codes is to know the requirements of the applicable code.

However, be aware that codes are adopted at the state, county, or city level and these entities may make modifications or amendments to the IECC and/or ASHRAE Standard 90.1.

It is also important to know if different codes are in force for different building types, including residential, commercial, state, or federal. If it is necessary to look up which code is in effect, there are a number of resources available, including BECP’s Status of State Codes Database, the International Code Council’s (ICC) adoption database, and the Building Codes Assistance Project (BCAP) Status of Codes Database.

Most energy codes make reference to other codes and standards.

  • The IECC references ASHRAE Standard 90.1.
  • The 2009 IECC also makes references to the International Mechanical Code or International Residential Code for items such as residential heating, ventilating, and air-conditioning (HVAC) load calculations, HVAC sizing, and duct sealing.
  • Both the IECC and ASHRAE Standard 90.1 refer to other standards organizations for testing and certification of materials and equipment.

These organizations include the American Society of Mechanical Engineers (ASTM), ASTM International, the Illuminating Engineering Society (IES), the National Fenestration Rating Council (NFRC), Sheet Metal and Air Conditioning Contractors’ National Association, and Underwriters Laboratories, among others.


  1. Building Energy Codes
  2. Building Energy Software Tools Directory
  3. ASHRAE Standard 90.1-2010
  4. ASHRAE Standard 189.1-2011
  5. ASHRAE eLearning
  6. ASHRAE Learning Institute
  7. ICC IECC and International Green Construction Code (IgCC) Online Learning
  8. ICC Bookstore
  9. ASHRAE Bookstore
  1. Current model energy codes cover design, construction, and testing up to and including commissioning for some buildings.