The desirability of energy codes is a given, but the question becomes which code to follow. The answer lies in where the project is located. Rather than mandating across-the-board changes, IECC code changes are only enforceable when they are adopted at the state or local level. Many jurisdictions do not adopt new versions of the code immediately after publication. When states or municipalities do adopt updated codes, they generally incorporate changes to reflect regional building practices, or state-specific energy-efficiency goals, sometimes deleting, supplementing, or otherwise changing various sections of the code. As of August 2012, the commercial code status is as follows:

• Most states and U.S. territories—38 out of 56—require ASHRAE 90.1-2007 / IECC 2009 equivalent or less.
• One state has stricter requirements.
• The rest have less stringent requirements.
• Ten states have no statewide code at all.

The maps on the previous page illustrate the commercial and residential energy code situation by state.

The U.S. Department of Energy

To see that the U.S. government is motivated and involved in improving energy standards in the built environment, one has only to look at the U.S. Department of Energy (DOE), whose energy goals are either driven by policy or law. As spelled out in the DOE's Annual Report for 2011, the agency's goals include cost effectively increasing energy efficiency in all buildings by 50 percent through more efficient building codes by 2015. DOE, through its Building Energy Codes Program (BECP), is working to enable 70 percent of states to adopt either the 2009 IECC, or ASHRAE Standard 90.1-2007, or better by 2015, and 90 percent of states to adopt these codes or better by 2017.

A Closer Look at the IECC 2012

Each revision of the IECC ratchets up energy performance requirements, and the 2012 revision is no exception. The major changes in the latest version of the code center on creating buildings that use 30 percent less energy than that required by the 2006 IECC edition—and targets for the 2015 code are 20 percent above the 2012 edition. Essentially, the code is heading toward a pronounced emphasis on building insulation and building envelope construction, with changes that affect building insulation values, fenestration, and air leakage.

Of prime importance to designers of masonry systems are the air barrier requirements. Air barriers systems are comprised of a number of materials which are assembled together to provide a complete barrier to air leakage through the building enclosure. They control the unintended movement of air into and out of a building enclosure—an important consideration in reducing energy costs as air leakage from a building can result in an increased use in energy costs of up to 30-40 percent in heating climates and 10-15 percent in cooling costs. Still, according to the Air Barrier Association of America, only Florida, Georgia, Maryland, Massachusetts, Minnesota, New York, and Rhode Island have air barriers in their codes.

The IECC 2012 version requires air barriers in both commercial and residential energy codes. Air barriers are now required in zones 4 – 8, with a continuous air barrier for the opaque building envelope required to comply with Sections 402.4.1.2.1, C402.4.1.2.2, or C402.4.1.2.3. The commercial code definition for an air barrier is the same as the residential code, with the following additional requirements:

• Materials – Air Permeance < 0.004 CFM/SF
• Assemblies – Air Permeance < 0.04 CFM/SF
• Building – Air Permeance < 0.4 CFM/SF
• Mandatory Testing

Relevant Web Sites

For further information on energy codes, architects will find the following links helpful. U.S. Dept. of Energy www.energycodes.gov Resource Guide for Architects www.energycodes.gov/resourcecenter/resource-guides Responsible Energy Code Alliance www.reca-codes.org Online Code Advocacy & Environment Network energycodesocean.org Building Codes Assistance Project bcap-energy.org/