State Profile

Code Type: Commercial Residential
Current State Code 2018 IECC and ASHRAE 90.1-2016 2018 IECC
Effective Date
Adoption Date
State Amendments No No
State Code Analysis*
Enforcement Mandatory Statewide Mandatory Statewide
Can use COM/REScheck Yes Yes


Commercial Residential
Current Model Code 2018 IECC 2012 IECC
Yes No
Previous Model Code
ASHRAE Standard 90.1-2010
ASHRAE Standard 90.1-2007
Previous Model Code
2009 IECC

Model Code Savings Potential

Statewide Savings Potential (2010-2030) Residential Commercial
Cost $0.31B $0.03B
Energy (primary) 16MBtu 3MBtu

Consumer Cost Savings

Consumer Cost Savings Residential
per Home
per 1,000 ft2
Annual ($) $6 $130
Annual (%) 0.2%
Life-cycle (30 year) $107 $1820
Simple Payback 0.3 years 7.1 years
Positive Cash Flow 0.0 years


Code Type: Residential Commercial
Field Study No No
Training Program No No


Additional Information

    Act 250 was first adopted in 1970 with the energy criteria added in 1973. Act 250 required that certain developments incorporate energy conservation measures that employed the best available technology based on life-cycle cost analysis. The Vermont Department of Public Service reviews and provides comments on Act 250 applications to the nine District Environmental Commissions that issue land use permits.


    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. Since that time, with the help of DOE Codes and Standards Grants, Vermont has aggressively implemented the residential code. The Vermont Energy Code Assistance Center was established to provide technical assistance, distribute code training materials and answer code compliance questions. A Vermont Residential Energy Code Handbook has been widely distributed and over 30 code training workshops have been held around the state. Two mechanical ventilation studies used in the development of a ventilation standard for the next residential code update have been completed.

    Vermont updated the RBES to meet or exceed the IECC 2000 in 2004 and revisions took effect January 2005. The VT RBES is approximately 5% more energy efficient than the IECC, and in the revision includes simple ventilation and combustion safety requirements, along with robust support for use or Home Energy Ratings as a primary compliance mechanism.


    Vermont published its IECC based 2001 Vermont Guidelines for Energy Efficient Commercial Construction in October 2001. The 2001 Commercial Guidelines incorporate ASHRAE /IESNA 90.1-1999 and a number of Vermont specific amendments. The 2001 Commercial Guidelines are currently under adoption as the single energy code for commercial buildings on a statewide basis. The 2001 Guidelines have been adopted by the City of Burlington for all commercial new construction and by the State of Vermont for state funded new commercial construction projects. The 2001 Guidelines have also been integrated into Vermont comprehensive land use development law, known as Act 250. The 2001 Guidelines establish minimum energy performance requirements for Act 250 permitted commercial and industrial developments throughout the state. The Act 250 energy criteria require that development projects in the state utilize the best available technology for the use and recovery of energy based on a reasonable estimate of life cycle costs.

    For commercial construction not currently subject to the 2001 Guidelines on a mandatory basis, Efficiency Vermont (the statewide energy efficiency utility) uses the Guidelines to establish baseline energy efficiency requirements under its commercial new construction program on a voluntary basis. Efficiency Vermont packages technical assistance and financial incentives to assist new construction projects throughout the state meet and exceed the ASHRAE/IESNA 90.1-1999 based 2001 Vermont Guidelines for Energy Efficient Commercial Construction.

    Compliance with the 2001 Vermont Guidelines for Energy Efficient Commercial Construction can be demonstrated through the Vermont version of the COMcheck-EZ compliance software (2.4 release 1). Additional information including the VT COM-check Compliance Guides to the 2001 Commercial Guidelines is available at the project website at: Vermont Energy Efficiency Resources.

    2001 Vermont Guidelines for Energy Efficient Commercial Construction based on 2000 IECC with amendments to incorporate and exceed ASHRAE/IESNA 90.1-1999, mandatory for state- funded new construction, ACT 250 projects and within the City of Burlington. Voluntary statewide as minimum performance criteria for new construction program operated by Efficiency Vermont, the states energy efficiency utility.

    Effective January 1, 2007, updated commercial energy code. The Commercial Building Energy Standards (CBES) was enacted into law in 2006 (21 V.S.A. 268). The CBES is the energy code for all commercial buildings and residential buildings four stories or greater above grade in Vermont. This code shall not apply to farm structures as defined in 24 V.S.A. 4413. The 2005 Vermont Guidelines for Energy Efficient Commercial Construction is a stand alone document for the State of Vermont based upon amendments to the International Energy Conservation Code 2004 Supplement. In addition the energy code allows an alternative path of ASHRAE 90.1-2004 with some Vermont-specific requirements that are outlined in the energy code handbook.

    The Commercial Building Energy Standard became effective January 3,2012. CBES incorporates elements of the 2012 IECC.

    RBES Revisions go through a process specified in the State Administrative Procedures Act (3 V.S.A. Chapter 25), including public notification, public hearing, testimony, and comments. The first revision to the 1997 RBES will occur in 1999 and subsequent revisions will be developed and adopted every three years thereafter. The 1999 revision will include ventilation standards and may include sealed-combustion and outside air requirements for wood and pellet stoves and fireplaces. Construction commencing after the effective date of an RBES revision must meet the revised RBES standard. Act 250 issues are addressed by the District Environmental Commissions or the appellate Environmental Board. The Burlington City Council oversees the Burlington city ordinance.

    The Vermont Department of Public Service must provide technical assistance and expert advice to the Commissioner of Labor and Industry on the interpretation of the RBES and in formulating specific revisions to the RBES. At least one year prior to adopting required revisions to the RBES, the Department of Public Service must convene an advisory committee to provide recommendations to the commissioner.

    Amendments to the RBES must be cost-effective and affordable for consumers and evaluated based on technical applicability and reliability. The effective date of any revisions must be at least three months after adoption.

    The Vermont Twenty Year Electric Plan (December 1994) states that while Act 250 has undoubtedly saved energy, the energy requirements are not effectively enforced. The standard for state-funded new commercial construction projects is also not effectively enforced. The Vermont Department of Public Service and several utilities have instituted an inspection process for Act 250 commercial projects. The city of Burlington Department of Public Works enforces the Burlington city ordinance.

    The RBES requires that a certification label be signed and permanently affixed in the home. The person certifying compliance must provide a certificate to the Vermont Department of Public Service and each certificate must be recorded and indexed in the town land records. The builder of the home, a licensed architect or engineer, or a Vermont-accredited home energy rating organization can certify compliance with the RBES. The RBES does not require inspections by code officials; however, it does not eliminate inspections related to Act 250, spot checks for enforcement of other codes, or inspections required by local codes.

    Act 250 compliance is determined by nine quasi-judicial District Environmental Commissions. The Vermont Department of Labor and Industry determines compliance for state-funded new commercial construction. The city of Burlington Department of Public Works determines compliance with the Burlington city ordinance. Burlington has adopted the RBES for new residential buildings and additions over 500 square feet.

    Compliance with the RBES is through self-certification by the builder on a one-page form. Five different ways to comply with the RBES are available after the list of basic requirements has been satisfied--1) a prescriptive list of features, 2) tradeoff variations, 3) VTcheck software, 4) a home energy rating greater than or equal to 82, or 5) an A/E systems analysis.

    A homeowner can seek damages within six years of occupancy if a home fails to meet the RBES.