What You Need to Know About the New Massachusetts Energy Code
By Peggy MacLeod, Sales Representative, and Aliza Heeren, Marketing High Performance Building Fellow
As of January 1, 2017, the Massachusetts Energy Code has adopted stricter energy efficiency standards required for all new homes. The state base energy code transitioned from the 2012 International Energy Code (IECC) standards to the 2015 IECC with a few specific amendments for Massachusetts. In addition, the Massachusetts stretch energy code, which has been adopted by over 180 Massachusetts towns, made a huge leap from the 2009 IECC requirements to the 2015 IECC requirements. This stringent new standard asks a lot of building professionals, and the Center for EcoTechnology is available to help make the transition as seamless as possible. CET has years of experience in high performance building and has performed over 2,000 HERS ratings. CET experts are available to assist builders through IECC code trainings, consultations, and HERS services.
If you are working in stretch code towns, here are a couple key changes that have taken place since the new 2015 IECC has been implemented:
- Building Envelope: The maximum building envelope leakage allowed in the 2009 IECC was 7 ACH50. This standard was not very taxing for most builders to achieve, however the new code allows a maximum air leakage of 3 ACH50, which will be much more challenging for builders to meet. CET raters are finding that a number of our tests are right on the pass/fail border, so we recommend being more attentive to air sealing during your construction.
- HERS Index: The maximum allowable HERS index (before including any renewable energy systems) is now 55, instead of 70 and 65 as in the previous energy code and stretch energy code respectively. While we are working with a number of homes that are in the mid-to-low 50 HERS index range, the smaller the home, the more challenging this rating is to achieve. As an alternative to reaching this HERS index, buildings can be certified as ENERGY STAR v3.1 or as a Passive House, which we have suggested as an alternative to multi-family developers for buildings with smaller units. A higher HERS index is allowed for homes with PV systems, clean biomass systems, solar thermal systems, and geothermal heat pumps.
These are just a couple of the changes in the IECC 2015 and suggestions for how you can best adapt. But don’t fret! CET raters have tips and recommendations for getting you to the goal of meeting the energy code. For more suggestions on how to meet the new energy code, attend one of our trainings, or contact us directly.
Finally, see CET early! Remember to get your preliminary HERS rating before you take permitting documents to the building inspector. Even though a few towns don’t ask for it up front, in order to ensure your building will meet new standards, it is essential to speak with a HERS rater early on in the process. It is difficult, at the end of a project, to retrofit a new home with a 65 HERS index to pass a 55 HERS index requirement and get your certificate of occupancy! Start the process early and stay ahead of the game.
If you have any questions, please contact us at 413-586-7350 x242.