Why Building Energy Codes?

Total Carbon Dioxide Emissions from Energy Consumption by Sector (2008)

Buildings fundamentally have an impact on people's lives, economic well being, and the United States' dependence on foreign oil, national security and the health of the planet. In the United States, residential and commercial buildings together use more energy and emit more carbon dioxide than either the industrial or transportation section.

Buildings use 39% of our total energy, two-thirds of our electricity, and one-eighth of our water. In light of these fundamental environmental issues, and the increasing cost of energy and our current economic challenges, building energy efficiency is a key component of sound public policy.

Because the efficiency with which a home, factory or office building will use energy is determined in part by decisions made far in advance of the actual use of that energy, the network of incentives and disincentives regarding energy choices is complex. Choosing less energy efficient methods of materials may save money upfront, but results in increased energy costs for the occupant of that building far in the future. The long term impacts of the choices and consequences result in a unique role for government in setting and enforcing building codes and standards, promoting improvements, and collecting and disseminating information regarding new technologies and best practices.

The Purpose of Building Energy Codes

Energy codes and standards set minimum requirements for energy-efficient design and construction for new and renovated buildings that impact energy use and emissions for the life of the building. They are part of the overall building codes, which govern the design and construction of buildings. Building energy codes set a baseline for energy efficiency in new construction by establishing minimum energy efficiency requirements. Improving the energy code generates energy savings in a consistent and long lasting manner. Buildings last a long time and an energy efficient building has the potential to save energy throughout the life span of the building. The benefits of more efficient construction today are enjoyed for 30-50 years.

Energy-efficient buildings offer both tangible and intangible energy, economic, and environmental benefits. They are more comfortable and cost effective to operate. The reduction in energy expenditures correlates to a reduced dependency on foreign oil which impacts national security. Studies also show a significant correlation in building energy use and environmental pollutants. Energy efficient buildings can also create economic opportunities for business and industry by promoting new energy efficient technologies. Unfortunately, the marketplace does not guarantee energy-efficient design and construction; however studies on operating costs and resale of commercial spaces built to higher energy efficiencies indicate a direct savings to homeowners and building occupants and financial benefits to building owners. Homebuyers often are motivated more by up-front costs than operating costs, unaware of the long term savings due to energy efficient construction.


New buildings, while they represent just over 1% of the total building stock in a given year, are important because they represent a unique chance to affect energy efficiency; keeping in mind that building energy codes also apply to retrofitting of existing buildings. Once a new building is constructed, it is very expensive and often impossible to achieve the energy efficiency that can be economically built in at the time of construction. Since buildings will be in existence for decades if not centuries this is an opportunity that we cannot afford to lose and had we done a more robust job in the past, retrofitting of existing buildings would not be as critical today. It is vital to make energy efficiency a fundamental part of the building design and construction process and energy codes are an effective way to achieve this goal and ensure energy efficiency is a component of all buildings. States have the lead to make this happen.

Research shows that contemporary energy codes could save about 330 Trillion BTU by 2030, almost 2% of total current residential energy consumption. There would also be comparable savings in consumer energy bills, air pollution and greenhouse gas emissions. Those savings help the state economy by putting more money is consumers' pockets and reducing environmental costs to the state and its industry.

This material has been adapted from the Building Energy Codes Project (BECP) website.