What are green and advanced codes?

Advanced and green energy codes direct the design and construction of more sustainable buildings that go beyond the minimum code requirements to reduce energy use and environmental impact even further. In this way, green and advanced codes are an important means to achieving climate goals set by many states and municipalities, as well as addressing the rising cost of energy. Although they both address building energy efficiency, advanced and green energy codes are not interchangeable terms.

Advanced codes

Energy codes that incorporate efficiency requirements that are more stringent than the national model energy codes are known as advanced codes, reach codes, or stretch codes. These energy efficiency provisions help to transform the marketplace and shape the development of future model codes by bringing high performing buildings into the mainstream and raising the ceiling for building energy performance.

Green codes

Green codes take the process a step further by promoting other aspects of sustainable buildings throughout their life-cycle. In addition to energy efficiency, they incorporate water conservation, building materials, resource management, renewable energy sources, occupant health, and environmental stewardship. Some green codes encourage investment in pedestrian infrastructure, proximity to public transit, and reduction in stormwater through an increase in permeable surfaces. By mandating construction based on these principles and promoting credible and practical building approaches, green codes help to create more sustainable communities.

In the last few years, the interest in adopting codes that establish green requirements (some combination of efficiency captured in the areas of energy, water, site, materials, and transportation) is rising. This interest can be leveraged to improve energy efficiency requirement with widespread support.

Green code adoption

In response to broad public concern over resource depletion and climate change, many states and municipalities are adopting building practices that result in energy-efficient, healthier, and environmentally sustainable buildings. Hundreds of cities, counties, and states have adopted some level of green codes. Many of them draw elements from the United States Green Building Council’s (USGBC) Leadership in Energy and Environment Design (LEED) and often state a minimum certification level that buildings must achieve. In some jurisdictions, only government-owned buildings are required to meet green code standards.

Model green codes

In 2008, the International Codes Council (ICC) and the National Association of Homebuilders (NAHB) developed the ICC 700, also known as the National Green Building Standard, which provides guidelines to green building practices that can be incorporated into new construction, including single and multifamily buildings and remodeled homes. Like the USGBC’s LEED for Homes, the National Green Building Standard also has a point-based rating system.

In January 2010, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), in conjunction with the Illuminating Engineering Society of North America (IESNA) and the U.S. Green Building Council (USGBC), published Standard 189.1, Standard for the Design of High Performance, Green Buildings Except Low-Rise Residential Buildings, the first U.S. commercial green building standard intended to be used in codes. According to a preliminary estimate by the U.S. Department of Energy (DOE) National Renewable Energy Laboratory (NREL), it is approximately 27 percent more energy efficient than Standard 90.1-2007, the national model code at that time. The ICC, in conjunction with a number of partners, also created a green code for new and existing commercial buildings in March 2010, the International Green Construction Code (IgCC), Public Version 1.0. The current version, released in June 2015, is the 2015 IgCC. Plans for the 2018 IgCC code development process are now underway.

Each of these publications will greatly assist states and jurisdictions by allowing the adoption of a nationally developed standard in codified language.