Americans spend almost 90% of their time inside buildings. According to the U.S. Energy Information Administration, more than 2⁄3 of the electricity generated and more than 1⁄3 of the total energy (including fossil fuels and electricity) in the U.S. are used to heat, cool, and operate buildings. Significant energy could be saved if all buildings, including current building stock, were built to, or exceeded minimum national energy code standards. Saving energy will result in fewer power plants and natural resources being used to provide electricity and natural gas. It also means fewer emissions to the atmosphere. Emissions have been attributed to smog, acid rain, and global climate change.
Energy codes provide minimum building requirements that are intended to reduce energy consumption. The U.S. Energy Conservation and Production Act (ECPA) requires that each state certify that it has a commercial building code that meets or exceeds ANSI/ASHRAE/IES Standard 90.1.1 When subsequent versions of 90.1 are published, the Department of Energy determines whether these more-recent versions meet the requirements of ECPA. The most-recent version of the standard was published in 2013 and has been determined to meet the provisions of ECPA. The International Energy Conservation Code (IECC) allows Standard 90.1 as a compliance path and also generally complies with ECPA. The most recent version of the IECC is 2015. In this sense, “commercial” means all buildings that are not low-rise residential (three stories or less above grade). This includes office, industrial, warehouse, school, religious, dormitories, and high-rise residential buildings. Some states implement codes similar to ASHRAE Standard 90.1 and some have other codes or no codes. The status of energy codes by states is available from the Building Codes Assistance Project (BCAP). Building to minimum energy codes is a cost-effective method of saving energy. The designer is not constrained in aesthetic expression in applying the range of available high-performance building systems to meet the performance criteria of ASHRAE 90.1 or the IECC.
Sustainability or green building programs such as LEED™, 4 Green Globes, or EnergyStar encourage energy savings beyond minimum code requirements. The energy saved is a cost savings to the building owner through lower monthly utility bills and smaller, and thus less expensive, heating, ventilating, and air-conditioning (HVAC) equipment. Less energy use also means fewer emissions to the atmosphere from fossil fuel power plants. Some government programs offer tax incentives for energy-saving features. Other programs offer reduced mortgage rates. The EnergyStar program offers simple computer programs to determine the utility savings and lease upgrades associated with energy saving upgrades. Sustainable buildings often have features that have been shown to increase worker productivity, decrease absenteeism, and increase student test scores in schools.
