U.S. homes are being built to higher standards of energy efficiency. The U.S. Department of Energy (DOE) is working to improve the energy efficiency of buildings through new technologies and better building practices. Energy-efficient buildings improve lives by saving consumers money, lessening the demand for fossil fuels, decreasing the need for new power generation, and reducing environmental emissions.
The International Code Council (ICC) makes sure that the homebuilding industry is using new, energy-efficient best practices. The council periodically regulates the quality of new home construction and updates the International Energy Conservation Code (IECC). Because of new advancements, the ICC periodically changes residential codes. According to the DOE, many of these changes make complying with the new code easier for the builder. But it's still the builder's responsibility to stay up-to-date and educated about these changes.
To keep informed, builders should take a proactive approach to evaluating home performance and keep up-to-date on code changes by visiting the DOE's Building Energy Codes Program website at www.energycodes.gov. The DOE's Building Energy Codes Program is an information resource on national model energy codes. The DOE works to promote stronger building energy codes and to help states adopt, implement, and enforce those codes. Strengthening energy codes increases the likelihood of energy and cost savings in new construction. Builders can design new buildings to be more comfortable and efficient, cutting heating and cooling costs by nearly 50%.
Recent changes to energy codes
Recently, the IECC made a change to the climate zones. A building has to comply with the climate zone requirements for the area where it will be constructed. The climate zones have been redefined, reducing their number from 19 to only eight. For builders, compliance should be easier, because the new climate zones honor political boundaries, such as state and county lines, and attempt to keep metropolitan areas together. The redefined climate zones also do a better job of integrating cooling considerations into the code. This is an important improvement, since air conditioning is a rapidly growing residential load.
The recent changes to the code have also resulted in simpler prescriptive requirements. The changes significantly reduce the time required for plan reviews and inspections. The glazing requirements are now independent of window area percentage, eliminating the vast majority of calculations needed to show compliance. With the recent changes, each climate zone has a single, stricter U-factor for windows, regardless of glazing percentage.
Other changes include when tradeoffs are used in compliance; requirements for sealed air handlers; changes in the locations where vapor barriers are required; and elimination of unused, redundant or conflicting definitions.
REScheck™
To help builders comply with energy codes, the DOE distributes compliance tools and materials. One new tool is REScheck™, which was formerly known as MECcheck. REScheck™ helps builders demonstrate compliance with the thermal shell requirements for new homes as set by the IECC. It allows a quick comparison of different insulation levels, so the builder can select a package that works best for the home. This tool makes life easier for builders by automatically generating the forms that must be submitted for the plan review and by requiring only a minimum amount of time and effort to learn and operate the program. To download the latest version of REScheck™, visit the U.S. Department of Energy's website at www.energycodes.gov/rescheck/download.stm.
Results of the Building Energy Codes Program
So far, the Building Energy Codes Program has resulted in energy savings of nearly $1 billion per year. The efforts have improved the energy efficiency of nearly 4 million new households. Every $1 spent on the Program has yielded more than $105 in annual energy savings. Program activities are projected to reduce the nation's primary energy use in 2010 by $7 billion in residential buildings. The cumulative energy cost savings due to the Program is estimated to be over $4.2 billion as of 2001—enough to provide all of the energy requirements for over 3 million homes for a year. By 2030, consumers will probably save $5.3 billion in energy costs.
When adopted, implemented, and enforced, stronger energy codes equal more energy-efficient buildings. The higher standards for building homes result in a greater conservation of natural resources and lower energy bills for homeowners. For the environment and the nation, conserving energy reduces pollution and lowers the demand for fossil fuels and dependence on imported energy. For builders, conserving energy means being able to market homes as being energy-efficient.
