The current iteration of the International Energy Conservation Code (IECC) applies to all commercial (including industrial and municipal) and residential new construction, renovation and modifications. Whether we realize it or not, it impacts the “green factor” of all of our lives. The code was first published in 1998; the goal of its creator, the International Code Council (ICC), was to address green requirements for new building construction and renovation.
How does that affect us? On an individual level, most people are free to choose the greenness of their lifestyle. Whether they choose to turn off the lights when they leave a room or choose to drink from a reusable container, people are free to conserve energy and natural resources or not. But on a broader level — a level that applies to all of us whether we realize it or not — although we may not be required to live green lifestyles, the requirement to construct greener buildings is being mandated and enforced.
IECC Code Sees Wide Adoption
Early versions of the code were not immediately enforced by many jurisdictions, but over time it has gained more recognition. According to the ICC, the code has been adopted or is being used in 45 states as well as the District of Columbia, Puerto Rico and the U.S. Virgin Islands. Individual cities are enforcing this code, too, including New York City and our corporate headquarters’ hometown, Kansas City, Mo.
The purpose of the IECC is to address minimum requirements for building energy efficiency and the conservation of natural resources. A U.S. Department of Energy (DOE) publication outlines the top 10 reasons for enforcing building energy codes. The reasons include protecting the environment from unnecessary emissions, saving energy and money for building occupants, and creating new jobs.
How the IECC Code Saves Energy and Money
The question that everyone is asking: How does this code save energy and money? The code contains energy efficient measures that have evolved from one version of the code to the next with input from the DOE, which indicates that the most recent version of the IECC is at least 30 percent more energy efficient than the 2006 IECC. The code’s energy efficiency can be achieved through prescriptive methods like minimum requirements for wall and window insulating values, mechanical heating and cooling performance and controls, lighting controls, and building air tightness, to name just a few. And, of course, minimum requirements may differ depending on the geographic location of the building and whether the building is for residential or commercial use.
Rather than using the prescriptive methods outlined in the code, designers can choose to use an overall building performance-based approach to prove compliance by comparing the predicted energy cost of the total building to a baseline energy cost of a similar building with a standard reference design. Proprietary modeling software packages can be used to demonstrate performance compliance.
The 2012 IECC also gives the owner the option of complying with other energy codes such as ASHRAE 90.1, “Energy Standard for Low-rise Residential Buildings," or an enhanced energy efficiency program such as the U.S. Green Building Council’s Leadership in Energy and Environmental Design, or LEED, rather than complying with the IECC.
This is the part that we think makes the refinements to the IECC Code most interesting — at least from a designer’s standpoint. The commercial portion of the IECC requires that a building design meet one of three optional design requirements when using the prescriptive approach to compliance. The three options are: use of heating, ventilating and air conditioning (HVAC) equipment that is more efficient than required by the code; use of special interior lighting power densities; or providing an on-site supply of renewable energy that meets minimum requirements.
Another code refinement affecting commercial buildings is the requirement to commission HVAC systems after building construction. Not only are designers required to design for HVAC energy efficiency, builders are required to prove that the building HVAC system operation meets the intent of the design. Although the IECC requires commissioning, authorities having jurisdiction may opt out of this requirement, as the City of Kansas City, Mo., has done.
Owners may not have the choice to design and construct energy-saving buildings. They’re required to do so; it’s as simple as that. But the IECC does give designers a choice as to how they design their buildings to save energy.
What do you think about the enhancements to the IECC Code? How is it impacting your design teams?
Angela Vawter has been an employee-owner of Burns & McDonnell since 1995 after her graduation from the University of Missouri-Columbia with a degree in Chemical Engineering. She is a wife and mother and enjoys reading, playing the piano, art, church activities and video games.
Image by Dept of Energy Solar Decathlon via Creative Commons