Energy Codes were first implemented in the late 1980’s. In 1992, the first nationwide energy code, known as 1992 MEC (for Model Energy Code) was published. In 2000, this code was picked up as part of the I -Code series. It has been published since 2003 as an Energy Code, with both commercial and residential sections. The commercial section is published as Chapter 11 of the IBC. The residential section is published as Chapter 11 of the IRC (International Residential Code). Wichita /Sedgwick County has adopted the 2006 edition of the IRC with Amendments. Chapter 11 is amended out of the local code. Since the 2006 code was published, 2009 and 2012 editions have been published. In 2015 a new edition will be published.
Codes are generally prescriptive. To meet a code you follow a recipe. Certain size wire for a 15 amp circuit. Larger wire for a 20 amp circuit. Fairly easy to follow and for the inspector to check. The same goes for framing, plumbing and other areas. These simple methods do not allow a Builder much flexibility. Fire Safety, Structural Integrity and Sanitation are not areas where the public has an interest in allowing much latitude in varying levels of safety.
Energy Efficiency Codes typically have several ways to comply. There is a prescriptive, follow the recipe method. There is a ‘Averaged U-Factor’ method. There is a performance method. We have seen how the prescriptive method works above. The ‘Averaged U-Factor’ approach requires a lot of mathematics and usually a computer program to make tradeoffs between several different areas of the structure. More insulation in the walls, for less in the attic and so on.
The performance path to compliance involves using visual, testing and software to measure the efficiency of the structure. In residential construction, the primary method across the US and Canada is uses the HERS Index.
The reasons a HERS Index Score can be tied into energy codes include:
- The inspection and testing protocols are established in RESNET’s national home energy rating standards. RESNET is a national not-for-profit membership standard setting organization. It is accredited by the American National Standards Institute (ANSI) as a Standard Development Organization.
- The professionals that undertake the inspection and performance testing are certified following RESNET’s standards stringent training and testing procedures.
- All certified RESNET home energy raters are subject to RESNET’s quality assurance oversight procedures.
- The RESNET national home energy rating standards are recognized by the federal government (U.S. Department of Energy, Environmental Protection Agency, Internal Revenue Service) various State Energy Offices, including the Kansas Energy Office, and the residential mortgage industry.
- The HERS Index is a trusted measurement of the energy performance of a home. Over one million homes have been issued a HERS Index Score in the US.
The HERS Index Score for meeting the Energy Code is used in:
• Arkansas, Colorado, Idaho, Kansas, Massachusetts, New Mexico and New York
• Over 150 local code enforcement agencies utilize the HERS Index to assess compliance.
The HERS Index Score is used in REALTOR® MLS Systems in these states:
• Colorado, Florida, Illinois, Maine, Minnesota, Nebraska. New Hampshire, Oklahoma, Texas, Vermont, Wisconsin, areas within Washington and Virginia also make the HERS Score available for Agents, Home Buyers, Builders, and Appraisers.
In 2013, HERS Ratings occurred on more than 50% of the new homes built in the US. The HERS Index is a widely accepted method of measuring and comparing energy efficiency from one home to another.