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Cummington is a Stretch Energy Code Community.

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What does this mean?


In 2009, Massachusetts became the first state to adopt an above-code appendix to the base building energy code known as the Stretch Code. The Stretch Code, which emphasizes energy performance as opposed to prescriptive requirements, is designed to result in cost-effective construction that is more energy efficient than that built to the mandatory state-wide IECC base code.

Stretch Code Compliance:

In order to meet the requirements of the Stretch Code, builders must hire a certified HERS Rater, like Home Energy Raters, to perform a series of tests (HERS Rating) to determine if the home meets energy code compliance. The Stretch Energy Code (2021 IECC w/ MA Amendments) has changed as of January 1, 2023, for residential buildings 3 stories or less. For 4+ story residential buildings, the 2023 Multifamily & Commercial Code went into effect on 7/1/23.

On 7/1/24, substantial changes to the Massachusetts building code went into effect for municipalities that have adopted the Stretch Energy Code. There is an overall push to remove fossil fuels from new buildings and higher HERS Ratings will be allowed for all-electric buildings.



Residential New Construction Projects:

  • HERS 42 for buildings with any mixed-fuel buildings
  • HERS 42 for buildings with any mixed-fuel buildings with solar electric generation
  • HERS 45 for all-electric buildings
  • HERS 45 for all-electric buildings with solar electric generation

Renovation/Addition Projects:

  • HERS 52 for buildings with any mixed-fuel buildings
  • HERS 55 for buildings with any mixed-fuel buildings with solar electric generation
  • HERS 55 for all-electric buildings
  • HERS 58 for all-electric buildings with solar electric generation

– 1 EV-Ready space and wiring per house required (EV-Ready also required for multi-family projects but requirements vary)
– ERV or HRV will now be required. Bath fans no longer meet the requirement for whole- house mechanical ventilation. There are some models we recommend using (with lower wattage) that help the HERS Rating, but you can use any brand you would like. You will still need to meet the required CFM of ventilation.
– HVAC duct leakage testing is now required for all systems, even if all ducts are within the conditioned envelope
– HERS Ratings will be required for additions over 1,000 sq ft and/or over 50% of the original structure (Level 3 Alteration per IEBC)


The following municipalities have adopted this new specialized Stretch Code:

Effective 7/1/23: Brookline, Cambridge, Somerville, Watertown
Effective 1/1/24: Action, Aquinnah, Arlington, Boston, Concord, Lexington, Lincoln, Maynard, Newton, Northampton, Sherborn, Stow, Truro, Wellesley, Wellfleet, Worcester
Effective 7/1/24: Amherst, Bedford, Carlisle, Chelmsford, Medford, Melrose, Needham, Norwood, Salem, Swampscott, Wakefield, Weston, Worcester
Effective 1/1/25: Ashfield, Ashland, Belmont, Dedham, Eastham, Easthampton, Hopkinton, Milton, Sharon, Wayland, West Tisbury
Effective 1/1/25:
Natick, Newburyport

Specialized Energy Code Compliance:

Specialized vs. stretch code for muti-family homes

Our team is here to help you meet these new code requirements. Please call our office at 508-833-3100 or send us an email to to schedule a time to review your upcoming 2023-2024 projects. We will work with you to help value-engineer your projects and maximize any available incentives.



Map of current energy code adoption in each municipality in MA