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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 ASHRAE Standard 90.1-2007 2009 IECC
Yes Yes

Model Code Savings Potential

Statewide Savings Potential (2010-2030) Residential Commercial
Cost $0.27B $0.07B
Energy (primary) 22MBtu 8MBtu

Consumer Cost Savings

Consumer Cost Savings Residential
per Home
per 1,000 ft2
Annual ($) $8 $144
Annual (%) 0.4%
Life-cycle (30 year) $131 $4150
Simple Payback 0.5 years 0.0 years
Positive Cash Flow 0.1 years


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

Additional Information



    In 1979, Delaware legislature passed Senate Bill 321 which established a minimum code for energy conservation. The legislation provided that no county or municipality may adopt a building or plumbing code that contradicts the energy requirements of the Model Code for Energy Conservation in New Building Construction (MCEC), a model code based on ASHRAE/IES 90-1975. This legislation established the minimum provisions within the state but left it up to the counties and municipalities to adopt a code that fits within the guidelines outlined in the bill.

    State legislation, through Senate Bill 83, adopted the 1993 MEC statewide in 1995 as codified in Section 7602 of Title 16 of the Delaware Code. The code became effective on July 1, 1996.

    The state then adopted the 2000 IECC for new residential dwellings three stories or less in height. For all other buildings, the 2000 IECC and its 2001 supplement (with reference to ASHRAE 90.1-1999) have been in effect since July 1, 2004.

    On July 29, 2009, Gov. Jack Markell signed SB 59 which mandated the adoption and enforcement of the most recent versions the model energy codes, the 2009 IECC and ASHRAE Standard 90.1-2007. COMcheck and REScheck software (and ENERGY STAR software as an alternative) may be used to demonstrate compliance. Subsequent versions of the two model energy codes would be reviewed for updates every three years. The bill also directs the Delaware Energy Office to establish a program for zero net energy capable buildings, with the goal of all new residential construction being net zero capable by December 31, 2025 and all new commercial construction being net zero capable by December 31, 2030. The legislation became effective July 1, 2010.

    State-Owned/Funded Buildings

    The Delaware Division of Facilities Management supports the activities of state government by accommodating state agencies' space needs, maintaining state facilities in good condition, and by implementing programs and initiatives to ensure each facility is energy efficient, architecturally accessible, and environmentally safe.

    Adoption Process

    The Delaware General Assembly considers new legislation in January of each year. Further legislative action is required to amend Section 7602 of Title 16 of the Delaware Code.

    Enforcement Process

    Enforcement is at the local level and left to code officials within the county or municipality. The Department of Administrative Services is responsible for enforcing compliance for state-owned buildings.

    Compliance Process

    Compliance with the energy code is determined at the local level and varies depending on the county or locality. The Delaware Energy Office will establish procedures for compliance certification. Local governments have the option of using alternative methods, such as the ASHRAE/IESNA 90.1-1999 Compliance Guide or COMcheck-EZ, to ensure that commercial buildings less than 5,000 sq. ft. meet the requirements of the code.