State and Local Policy Database

Residential Codes

Mandatory residential building codes require a minimum level of energy efficiency for new residential buildings. The Department of Energy estimates that between 1992 and 2012, residential codes resulted in cumulative energy savings of 1.8 quads. They project that an additional 21.2 quads will be saved through 2040 due to residential building energy codes.

The Alabama Energy and Residential Code (AERC) Board recently adopted the 2015 Alabama Residential Energy Code. While the residential code is based on the 2015 IECC, state-specific amendments weaken it significantly and make it comparable to the 2009 IECC. The updated residential code will take effect October 1, 2016. Local jurisdictions may adopt more stringent codes, and several have adopted the 2015 IECC without the state-adopted amendments.

Last Updated: September 2016

Alaska does not have a mandatory statewide code for new residential construction. However, since July 2013, residential construction projects financed by the Alaska Housing Finance Corporation have been required to meet the state-developed Building Energy Efficiency Standards (BEES), which is based on the 2012 IECC with state-specific amendments. Since the corporation finances approximately 20% of the market share, the majority of homes in Alaska are built to this standard. In addition, Alaska's Cold Climate Housing Research Center (CCHRC) found that about 68% of new residential construction adheres to BEES.

Last Updated: September 2016

Arizona is a home-rule state, meaning that codes are adopted and enforced on a local rather than state level. However, the Southwest Energy Efficiency Project has found that the majority of new construction activity occurs in jurisdictions who have adopted the 2012 IECC.

Last Updated: September 2016

The Arkansas Energy Code for New Building Construction is mandatory state-wide for both residential and commercial buildings. The residential energy code is based on the 2009 IECC with amendments. This code became effective on January 1, 2015.  

Last Updated: June 2016

The 2013 Building Energy Efficiency Standards, effective July 1, 2014, are mandatory statewide and exceed the 2012 IECC standards for residential buildings. The 2016 Standards were adopted in June 2015, effective January 1, 2017, and are expected to exceed the 2015 IECC standards for residential buildings. California’s voluntary reach standards, which local governments are encouraged to adopt as mandatory, are adopted in the 2013 California Green Building Standards – Tier I and Tier II, effective July 1, 2014.  The 2016 reach standards were adopted in October 2015, effective January 1, 2017, and establish standards for Design Ratings that are 15% (Tier I) and 30% (Tier II) beyond the mandatory standards, as well as a Zero Net Energy Design designation, that local governments consider for adoption as local ordinances.

Last Updated: June 2016

The 2003 IECC is a mandatory minimum for jurisdictions that have adopted a code previously. Jurisdictions that have not adopted or enforced codes are exempt from the 2003 IECC requirement, although the 2012 IECC is mandatory for all factory-built and multi-family structures – commercial and residential – in areas that do not adopt or enforce buildings codes. 95% of all residential new construction takes place in jurisdictions that have adopted the 2009 IECC or better.

Last Updated: June 2016

In 2009, the state of Connecticut adopted the target code IECC 2009 pursuant to PA 09-192, with the new code going into effect on October 7, 2011. PA 09-192 requires the incorporation of the 2012 IECC within 18 months of its publication. The Department of Administrative Services, Office of the State Building Inspector, in conjunction with the Codes & Standards Committee, has released a notice of intent to adopt the 2016 Connecticut Fire Safetey Code, including the 2012 IECC, and is expected to implement the code by October 2016. The draft residential energy code, however, includes significant weakening amendments.

Last Updated: September 2016

Residential construction in Delaware must comply with a weakened version of the 2012 IECC. The state is currently reviewing the 2015 IECC and anticipates adoption, with minor amendments, by May 2017. Residential and commercial codes are reviewed triennially by the Delaware Energy Office within the Department of Natural Resources and Environmental Control.

Last Updated: September 2016

Washington DC's energy codes are mandatory across the District. For residential buildings, builders must comply with the 2013 DC Energy Conservation code, which is roughly equivalent to the 2012 IECC.

Last Updated: June 2016

Effective June 30, 2015, Florida law requires that residential buildings comply with the 5th Edition (2014) Florida Building Code, Energy Conservation. The 5th Edition (2014) Florida Building Code, Energy Conservation consists of the foundation code 2012 IECC and amendments. The FBC certified in letters to the U.S. DOE that the new code meets or exceeds 2012 IECC standards. Compliance with the code is mandatory for all new construction including alteration to existing buildings.

Last Updated: June 2016

On January 1, 2011, the 2011 Georgia State Minimum Standard Energy Code became effective statewide as approved by the Georgia Department of Community Affairs on November 3, 2010. The state code is based on the 2009 IECC with 2011 Georgia Amendments and is mandatory statewide.

Last Updated: June 2016

In July 2015, the Hawaii State Building Code Council adopted the 2015 IECC with state-specific amendments. The new codes took effect on July 1, 2015. However, until each county adopts the 2015 IECC, the counties of Hawaii, Maui, and Honolulu enforce the 2006 IECC; Kauai, the 2009 IECC. 

Last Updated: June 2016

Effective January 1, 2015, the 2012 IECC became mandatory statewide for residential and commercial new construction, the latter with reference to ASHRAE 90.1-2010. However, the state incorporated amendments to the residential codes that removed all the energy efficiency improvements from the 2012 IECC, so that the codes are still equivalent to the 2009 IECC. 

Last Updated: June 2016

By law Illinois is required to adopt the latest IECC, although the Capital Development Board may recommend amendments. Current code, effective January 2016, requires residential construction to meet 2015 IECC standards with state-specific amendments. 

Last Updated: June 2016

The Indiana Energy Conservation Code is state-developed and mandatory statewide. For residential buildings, the 2011 amendments update the 2005 Indiana Residential Code to reference Chapter 11 of the 2009 IRC, with the amendments meeting the stringency of Chapter 4 of the 2009 IECC, effective as of April 5, 2012.

Last Updated: June 2016

The Iowa State Energy code is mandatory statewide for residential buildings, although jurisdictions are free to adopt stricter codes. As of March 2014, residential buildings must comply with the 2012 IECC, with state-specific amendments. The state is in the process of holding public meetings to adopt the 2015 IECC.

Last Updated: June 2016

Kansas is a home-rule state and thus has no statewide residential building code, though realtors and homebuilders are required to fill out an energy-efficiency disclosure form and provide it to potential buyers. Many jurisdictions have adopted the 2009 or 2012 IECC. Based on information obtained in a 2013 survey of local jurisdictions and 2011 U.S. Census permit data, it is estimated the almost 60% of residential construction in Kansas is covered by the 2009 and 2012 iterations of the IECC. 

Last Updated: June 2016

As of October 1, 2014, the 2013 Kentucky Residential Code (KRC) mandates residential buildings must comply with the 2009 IECC or IRC with state amendments.

Last Updated: June 2016

Residential buildings must meet the 2009 IRC with reference to the 2009 IECC. Multifamily residential construction three stories or less must comply with the 2012 IRC and the energy provisions of the 2009 IECC. Multifamily residential construction over three stories must comply with ASHRAE 90.1-2007.

Last Updated: June 2016

The Maine Uniform Building and Energy Code (MUBEC) was established legislatively in April 2008 through P.L. 699, setting the 2009 IECC and ASHRAE 90.1-2007 as the mandatory for residential buildings statewide, effective June 1, 2010 with a six-month transition period. In 2011, P.L. 408 changed mandatory enforcement requirements for the Maine Uniform Building and Energy Code (MUBEC) to municipalities with populations over 4,000 starting December 1, 2010 for municipalities that had existing building codes and December 1, 2012 for municipalities that did not have existing building codes. For municipalities with a population less than 4,000 enforcement of the statewide code is voluntary. This change means that 89 of Maine’s 533 municipalities (based on 2010 census data) are required to provide enforcement of energy codes, representing 60% of the state’s residential population. The Technical Codes and Standards Board is currently working on the adoption of the 2015 IRC, IEBC, and IECC.

Last Updated: June 2016

Effective January 1, 2015, the 2015 Maryland Building Performance Standards are mandatory statewide and reference the 2015 ICC Codes, including the 2015 IECC, for all new and renovated residential buildings. § 12-503 of the Maryland Code requires the Department of Housing and Community Development to adopt the most recent version of the IECC twelve (12) months after it is issued and may adopt energy conservation requirements that are more stringent than the codes, but may not adopt energy conservation requirements that are less stringent. Each locality in the state must adopt and begin enforcement of the code within 12 months of state adoption. All counties and Baltimore City have adopted and are enforcing the 2012 IECC.

Last Updated: June 2016

In July 2015, the Board of Building Regulations and Standards (BBRS) began development of the MA 9th edition building code, which is expected to be effective between July 1, 2016 and January 1, 2017. The energy chapters the IECC 2015 and ASHRAE 90.1-2013 with strengthening amendments. The public comment period on this code is currently open and a BBRS vote on adoption is expected this summer. Until the IECC 2015 and ASHRAE 90.1-2013 takes effect the energy code remains the 2012 IECC and ASHRAE 90.1-2010, with state-specific amendments. The MA amendments add a HERS compliance path for units that receive a HERS rating of 65 or less, and a compliance path for buildings that use the Passive House software (PHPP). Massachusetts has achieved broad adoption of the 2009 MA Stretch Energy Code. It is currently adopted in 162 towns and cities representing over 50% of the state population. The MA stretch energy code requires residential new construction to follow the ERI path of the IECC 2015 with a HERS rating of 55 or less, and also includes renewable energy trade-offs to promote both solar PV and renewable heating. 

Last Updated: July 2016

The 2015 Michigan Residential Code went into effect in February 2016 and is based on the 2015 IECC with Michigan-specific weakening amendments.

Last Updated: July 2016

Minnesota's residential building code is mandatory statewide. The IECC 2012 was adopted in August 2014 and went into effect February 2015.

Last Updated: June 2016

Mississippi's residential code is voluntary and is based on ASHRAE 90 – 1975 and the prior 92 MEC. Based on a June 2011 Energy Codes Economic Analysis conducted by BCAP and Southface, as well as additional data collected by MDA, approximately 60% (1.75 million out of a total 2.9 million residents) of the State’s population reside in cities or counties with building codes equivalent to 2003 IBC or higher, and the average code standard for these local jurisdictions is 2006 ICC. Jurisdictions can adopt more stringent codes, and several localities have done so for the residential code: Gulfport, Biloxi, Horn Lake, Ridgeland, Jackson, Greenville, Oliva Branch, Pascagoula, and Moss Point.

Last Updated: June 2016

Missouri is a home-rule state and thus has no mandatory state-wide codes. State-owned residential buildings must comply with latest edition of the MEC or the ASHRAE 90.2-1993 (single-family and multifamily buildings). Missouri maintains a database of building code adoptions in local jurisdictions. Approximately 50% of the state’s population is covered by the 2009 or 2012 IECC or equivalent codes.

Last Updated: June 2016

Montana's residential building code, codified in ARM Title 24, Chapter 301.160, is mandatory statewide. Montana's residential code requires compliance with the 2012 IECC, with amendments.

Last Updated: June 2016

Nebraska is a home-rule state, but its residential energy code, referred to as the Nebraska Energy Code (NEC), is mandatory statewide. Residential buildings are required to comply with the 2009 IECC with administrative amendments. Local jurisdictions can adopt any code that is more stringent than the NEC, and two municipalities have adopted the 2012 IECC: Gretna and Fremont. Nonetheless, 100% of new homes fall under the 2009 IECC as the NEC is the minimum standard. The Energy Office has conducted a study on the impact of the 2015 IECC, and is awaiting the final report.

Last Updated: June 2016

On July 1, 2015, the 2012 IECC became mandatory for residential buildings. While the code is not being enforced statewide, a significant number of localities have adopted it. Local jurisdictions are not allowed to adopt less-efficient energy codes.

Last Updated: September 2016

Effective April 1, 2010, the New Hampshire State Building Code for residential buildings is based on the 2009 IECC, with state-specific amendments. The code is mandatory statewide. The NH Building Code Review Board is currently reviewing the 2015 IECC.

Although New Hampshire is not a home rule state, statutes allow municipalities to adopt amendments and codes provided they exceed the State Building Code. The town of Durham has adopted the 2015 IECC energy code (strengthened).

Last Updated: July 2016

The 2015 New Jersey Uniform Construction Code for residential and commercial buildings is mandatory statewide as of September 2015. Residential construction must comply with an amended version of the 2015 IECC.

Last Updated: September 2016

The 2009 New Mexico Energy Conservation Code (NMECC) is based on the 2009 IECC with state-specific amendments for residential building codes. All areas of the state are covered by local building jurisdictions and must meet or exceed the state minimum code. Because localities are permitted to adopt stretch codes, the City of Santa Fe and Town of Taos have adopted more stringent building codes. Builders can also use the NM 2009 Energy Conservation Code Residential Applications Manual to comply when building a passive solar or high mass home.

Last Updated: July 2016

In March 2016, the New York State Fire Prevention and Building Code Council updated the 2016 Energy Conservation Construction Code of New York (ECCCNYS 2016), incorporating the 2015 IECC, ASHRAE 90.1-2013, and 2016 Energy Code Supplement. Effective October 3, 2016, residential buildings will need to comply with the 2015 IECC.

The State Fire Prevention and Building Code Council is empowered to adopt higher or more restrictive standards upon the recommendation of local governments. Several municipalities in New York State, including New York City, have adopted more stringent requirements as part of local code, such as EnergyStar, minimum HERS scores, benchmarking and early adoption of the 2012 IECC.

Last Updated: July 2016

The 2012 North Carolina Energy Conservation Code (NCECC) is mandatory statewide for residential buildings. The residential code is based on the 2009 IECC with substantial strengthening amendments.

Last Updated: July 2016

North Dakota is a home rule state and has no statewide mandatory energy codes. Approximately 83% of the state’s population lives in a jurisdiction that has adopted the ND State Building Code which includes the 2009 IECC.

Last Updated: July 2016

Ohio's residential energy code is mandatory statewide and requires compliance with the 2009 IECC. Residential home builders are also allowed to meet the requirements of sections 1101-1103 of Chapter 11 of the Residential Code of Ohio (based on Chapter 11 of the 2009 IRC) or by meeting the state code's new Prescriptive Energy Requirements (section 1104).

Last Updated: July 2016

Oklahoma has in place mandatory statewide building codes for residential buildings. In June 2009, the Oklahoma Legislature passed a bill (SB 1182) creating the Oklahoma Uniform Building Code Commission (OUBCC) that reviews and recommends building codes for residential construction for adoption (BCAP 2012 ). Beginning in October 2010, the Commission held several meetings discussing code change proposals. On March 31, 2011, the Commission formally recommended a residential code based on the 2009 IRC with state-specific weakening amendments amendments. The statute became effective July 15, 2011. The state recently adopted amendments to bring the code up to equivalent to the 2009 IECC, which will go into effect November 1, 2016.

Last Updated: September 2016

The 2011 Oregon Residential Specialty Code (ORSC) is mandatory statewide. Its provisions are developed by the state and are not based on a model code. The energy provisions of the ORSC were compared to the 2012 IECC residential provisions using EnergyPlus models developed by the US Department of Energy (PNNL) models. The weighted average of the Oregon measures was equivalent to the 2012 IECC.

Oregon is has approved IECC 2015 as an alternative and is putting in place provsions for it to replace the current Reach Code. Reach Code compliance is mandatory for all new state-owned and occupied buildings and substantial remodels.

Last Updated: July 2016

Pennsylvania's residential energy code is mandatory statewide. Residential buildings must comply with the 2009 IECC or 2009 IRC, Chapter 11. Residential buildings can also comply with Pennsylvania’s Alternative Residential Energy Provisions (2009). Municipalities can propose more stringent codes to the Department of Labor and Industry, the approving authority. All 2,562 jurisdictions have mandatory building energy codes for residential and commercial construction.

Last Updated: July 2016

On July 1, 2013, Rhode Island formally adopted the 2012 IECC for residential buildings, with state-specific amendments. The code went into effect on October 1, 2013 and is mandatory statewide. While Rhode Island is a home rule state, towns are not permitted to adopt a code that is different from the state's. Rhode Island amendments include the continuation of the 2009 insulation table for residential building envelopes, and the stipulation that every new residential building must undergo performance testing, but does not need to achieve specific performance target levels in order to receive a certificate of occupancy. While there is no current stretch code, as part of the Rhode Island’s Energy Efficiency Procurement Plan, a Building Codes & Standards Initiative has been approved by the RI Public Utilities Commission, and a stated feature is the development of a “stretch” code targeting “15% more energy than buildings constructed according to the prevailing path.” This effort is being pursued in conjunction with the RI Building Code Commission and the RI Builder’s Association.

Issued in December, 2015, Executive Order 15-17 directs the Office of Energy Resources to coordinate with the Energy Efficiency and Resource Management Council, National Grid, and the Green Building Advisory Committee to establish a voluntary aspirational or stretch building code based on the International Green Construction Code or equivalent by 2017. The group aims to develop a draft residential stretch code by July 1, 2017 and formalize the adoption of the code by December 31, 2017.

Last Updated: September 2016

On January 1, 2013, the 2013 South Carolina Energy Standard became effective. The residential provisions reference the 2009 IECC. Local jurisdictions may adopt more stringent energy codes.

Last Updated: July 2016

South Dakota has no mandatory statewide energy codes for residential construction. Codes are adopted by jurisdiction voluntarily. As of July 2011, state law established the 2009 IECC as a voluntary residential standard. Local jurisdictions also have authority to adopt various residential building and energy codes, including IRC and IECC.

Last Updated: July 2016

Tennessee is a home rule state, which gives jurisdictions the power to adopt codes. Under Tennessee statute, all local jurisdictions must adopt a residential energy code that is within seven years of the currently adopted State energy code, but they may also opt out of adoption with a two-thirds majority vote of the local governing body. In addition, local jurisdictions cannot be required to adopt a local code that is more stringent than the one adopted by the State but may voluntarily choose to adopt an updated code version. If opting out, the vote must be completed after each local election cycle. To date, 80 of 468 jurisdictions, including both municipalities and counties have opted out. Roughly 88% of the state population resides in jurisdictions that either participate in the State Residential Building Program or have adopted their own mandatory residential building codes that are within 7 years of the State Residential Building Code.

The Tennessee State Fire Marshal’s within the Department of Commerce and Insurance (C&I) adopts and enforces state building codes. The state currently enforces the 2006 IECC for all one and two family buildings and townhouses. On November 2, 2015, C&I conducted a rulemaking hearing to adopt the 2009 IECC for residential one and two family dwellings and townhouses. The residential rules are still being reviewed by the Attorney General's Office. It is anticipated that these rules will become effective later in the summer of 2016. 

Last Updated: July 2016

Texas' building codes are mandatory for residential construction. Effective September 1, 2016 Texas Building Energy Performance Standards require single family homes to comply with the 2015 IRC. For all other residential buildings, the 2015 IECC will go into effect November 1, 2016. For all buildings, jurisdictions can choose to adopt more stringent standards. More than 50 jurisdictions, representing approximately 5.3 million people, have adopted codes more stringent than the minimum state requirements. 

Last Updated: July 2016

Utah’s Uniform Building Code (UUBC) for residential building energy codes is mandatory statewide. Effective July 1, 2016, residential building construction must comply with an amended version of the 2015 IECC. While localities may adopt stretch codes, it is a difficult process to do so. As a result, none have adopted stretch codes.

Last Updated: July 2016

Vermont’s residential building energy code is mandatory statewide. Effective March 1, 2015, the RBES references the 2015 IECC with Vermont-specific amendments. The state is required by statute to update its codes every three years. 

Act 89 of 2013 gives the Vermont Public Service Department the authority to develop stretch codes and municipalities have the option of adopting them. The state's Residential Stretch Energy Code goes into effect on December 1, 2015. Any projects encompassed by Residential Act 250 are required to adopt the Residential Stretch Code. Thise code has a higher level of thermal energy efficiency than the Base CodeBoth Residential Base and Stretch Energy Codes also allow renewable energy to be used to meet the target Home Energy Rating Scores for compliance. Additionally, the Residential Stretch Code has Electric Vehicle charging requirements for multifamily developments of 10 units or more. 

Last Updated: July 2016

Virginia’s Uniform Statewide Building Code (USBC) is mandatory statewide for residential buildings. Residential buildings must comply with the 2012 IRC; however, a few technical amendments were made to the residential energy code requirements and no significant improvements were adopted, rendering the residential code equivalent to the 2009 IECC. The state is currently reviewing the 2015 IECC. 

Last Updated: July 2016

The 2015 Washington State Energy Code is a state-developed code that is mandatory statewide. The 2015 version of the residential code is based on the requires compliance with the 2015 IECC, with additional requirements providing an additional 17 reduction in energy use. The City of Seattle adopts an energy code that achieves greater savings than the Washington State Energy Code.

The Washington State Code Develpment Group was awarded the Jeffery A. Johson Award, in part to recognize our recent accomplishments. 

Last Updated: July 2016

West Virginia's residential building code is mandatory statewide; however, adoption by jurisdictions is voluntary. The 2013 West Virginia Legislature passed a bill updating the state’s building energy code to follow the 2009 IECC for residential buildings. The new residential code became effective November 30, 2013.

Last Updated: July 2016

The state-developed residential code, referred to as Wisconsin Administrative Chapter SPS 322, Wisconsin Uniform Dwelling Code (UDC), is mandatory statewide for one- and two-family dwellings and incorporates the 2009 IECC with state amendments. These amendments are more restrictive for underfloor insulation for heated slabs.  Local governments cannot modify the UDC and are required to enforce the UDC.  

Last Updated: July 2016

Wyoming's residential building code is voluntary. Known as the ICBO Uniform Building Code, it is based on the 1989 MEC and may be adopted and enforced by local jurisdictions. Some jurisdictions have adopted more stringent codes than the voluntary standard: the 8 most populated cities and counties in Wyoming have an energy code that meets or exceeds the IECC 2006 or equivalent. Teton County and Jackson are moving to the IECC 2012; Cheyenne adopted the IECC 2009; Casper, Rock Springs, and Gillette adopted a modified IECC 2006.

Last Updated: July 2016