Not sure which energy code requirements apply to your project? Find out!

Energy Codes in Massachusetts

With over 25+ years of experience in the industry, our team of 9 RESNET Certified HERS Raters and 4 Rating Field Inspectors has the knowledge and expertise you need to ensure that your project complies with all energy codes. Click here to learn more about our energy code compliance services.



Massachusetts has a base energy code that all new buildings in the state must follow. It is based on the most current version of the International Energy Conservation Code (IECC) which establishes a baseline for energy efficiency by setting performance standards for the building envelope. Provided the mandatory requirements are met, the rest of the code can be met by either following the prescriptive or performance path.

Performance Path Compliance:

The performance path requires energy modeling to demonstrate that the building as a whole uses equal or less energy than a home built to the prescriptive path. Even though the performance path is slightly more involved, it allows flexibility to trade off many of the high-cost assemblies required in the prescriptive path resulting in substantial savings.

To comply with the Performance Path, you will need either a simulated energy performance analysis or an Energy Rating Index (ERI) analysis. The ERI path, specifically a certified RESNET HERS Rating, is the performance path most often used to achieve energy code compliance in base energy code communities.

We highly recommend following the Performance Path utilizing a HERS Rating.  A HERS Rating is the most realistic compliance option that offers documented energy savings while giving you more flexibility and “trade offs”.

Prescriptive Path Compliance:

The prescriptive path requires that each component is built to a specified R-value or U-value found in the prescriptive table. While the prescriptive path is a traditional approach and can be achieved without the aid of any software, it does not have much flexibility and therefore does not allow trade-offs to lower assembly cost.

To comply with the Prescriptive Path, you will need:

  • A REScheck certificate
  • Performance Testing – blower door test, duct testing, and ventilation testing
  • To meet insulation specifications
  • To meet window performance specifications

**This path is not eligible for Mass Save incentives**

IECC/HERS Compliance Specialist

As a certified IECC/HERS Compliance Specialist, Home Energy Raters can now help code officials save time, energy and resources by assisting with code jurisdiction and energy code compliance.  To learn more, click here.




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. New homes being built in these municipalities must follow the Performance Path and get a HERS score of 55 or less.  Many renovations in these towns also require a HERS Rating and must get a HERS score of 65 or less.

Most municipalities in Massachusetts have adopted the Stretch Code – take a look at the map below to see if the town/city you are building in has adopted this new energy code. For more information about about the Stretch Code, check out out our “Stretch Code Q&A” article.





Home Energy Raters