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Building Energy Code

Summary of State Building Energy Codes including the Stretch Code

Table of Contents

Energy Efficiency Provisions of the State Building Code (780 CMR)

As part of the Green Communities Act of 2008, Massachusetts is required to update its building code every three years to be consistent with the most recent version of the International Energy Conservation Code (IECC).

Ninth Edition of the MA State Building Code 780 was filed with the Secretary of State on Friday, Oct. 6, 2017 and became effective on Oct 20, 2017 .

Ninth Edition Base Code, of particular interest is 780 CMR 13 (commercial energy efficiency standards)

Ninth Edition Residential Code, of particular interest is section 11 of 780 CMR 51 (residential energy efficiency standards), and 780 CMR 115 Appendix AA (Stretch Energy Code).

Stretch Code Summary

In 2009, Massachusetts became the first state to adopt an above-code appendix to the "base" building energy code-the "Stretch Code" (780 CMR Appendix 115.AA). 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 "base" energy code. Alongside the base code update to the IECC 2015, the Stretch Code is being updated, and is referred to as the 2015 Stretch code update.

Additional Resources

Stretch Code Adoption by Community

Stretch Code Adoption by Community Map and List

Municipalities may choose to adopt the Stretch Code in lieu of the base building energy code. Stretch code adoption is mandatory for designation as a Green Community under the Green Communities Act passed by the Legislature and signed into law in 2008. As of August 25, 2020, 284 municipalities have adopted the Stretch Code. Building code officials have received free code training.

Additional Resources

Stretch Code “Residential Cash Flow Analysis”

In 2016, DOER hired an independent building energy consulting firm to look at the cost-benefit equation of building a representative set of new single-family and multi-family homes to the updated 2015 stretch code. The analyses were updated in August 2017.  There are examples of both gas heated and non-gas heated homes, all of which show that homeowners see a positive cash-flow from day 1 from purchasing a 2015 stretch code home vs. a 2015 base code compliant home.

Click here for analysis

Massachusetts Energy Code Training

The Mass Save statewide energy efficiency program in coordination with the Board of Building Regulation and Standards (BBRS) and DOER is continuing to sponsor training on the building energy code, including the Stretch Code, at various locations around the state. The training is open to all, and developed to serve both building officials and other building professionals (e.g., builders & architects). Training is free for building officials, and counts toward the new BBRS requirement that building officials be trained in energy efficiency. Other building professionals pay a nominal fee for the training, and may receive continuing education units (CEU's) for attending. 

To get information on energy code training and events, click here.



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