Residential: In 1997, the State of Vermont enacted the Vermont Residential Building Energy Standards (RBES), a statewide residential energy code based on the 1995 CABO/MEC. It became effective July 1, 1998.
The 2005 RBES edition was based on the 2000 IECC and became effective January 1, 2005.
Commercial: Vermont published its IECC-based 2001 Vermont Guidelines for Energy Efficient Commercial Construction in October 2001. The 2001 Commercial Guidelines incorporated ASHRAE Standard 90.1-1999 and a number of Vermont-specific amendments.
The Commercial Building Energy Standards (CBES) was enacted into law in 2006 (21 V.S.A. § 268) a the energy code for all commercial buildings and residential buildings four stories or more above grade in Vermont. The 2005 CBES was based on the 2000 IECC and ASHRAE Standard 90.1-2004 and became effective on January 1, 2007.
Automatic Update Legislation: On May 27, 2009, the state legislature passed the Vermont Energy Act of 2009, which directs the Commissioner of the Department of Public Service to adopt the 2009 IECC and ASHRAE 90.1-2007 as well as develop a plan to achieve compliance with these codes in 90% of new building space within eight years (as directed by the federal stimulus legislation ARRA, or the American Recovery and Reinvestment Act). Every three years after that date, the Department of Public Service shall update the residential and commercial codes to incorporate the most recent versions of the IECC and ASHRAE Standard 90.1, with an effective date within three months of final adoption.
By September 1, 2011, the Commissioner must also issue a plan to achieve 90% compliance by February 1, 2017. The Commissioner must also establish training and enforcement programs as well as a system to annually measure the compliance rate by June 30, 2012.
2011 Code Updates: On July 1, 2011, the Department of Public Service updated the 2011 Vermont Residential Building Energy Standards (RBES) to reference the 2009 IECC with several strengthening amendments from the 2012 IECC (the 2005 RBES currently is based on the 2000 IECC). The revisions will take effect October 1, 2011 and will apply to all new residential construction, including alterations, renovations, repairs, and additions larger than 500 square feet. The state updated its Vermont Residential Energy Code Handbook for the RBES webpage.
On October 3, 2011, DPS officially updated the 2011 Vermont Commercial Building Energy Standards (CBES) to reference the 2009 IECC and ASHRAE Standard 90.1-2007 with several strengthening amendments from the 2012 IECC (the current 2005 CBES is based on the 2000 IECC and ASHRAE 90.1-2004). The revisions take effect January 3, 2012 and will apply to all commercial construction, including alterations, renovations, repairs, and additions.