The Building Department would like to inform residents that a newly updated Stretch Energy Code now requires certain home additions and/or alterations to comply with the same code requirements of a new construction home, including a HERS Index Score. This means additional energy upgrades of the existing home above and beyond the immediate work area may be required.

A HERS (Home Energy Rating System) Index is the industry standard by which a home's energy efficiency is measured, which must be completed by a third-party energy consultant.

Additions and alterations that meet the below thresholds will require the dwelling unit to achieve a specific HERS Index Score.

Additions that are over 1,000 square feet or exceed 100% of the conditioned floor area of the existing home.

Alterations over 1,000 square feet exceed 100% of the conditioned floor area or 50% of the total building area. (Level 3 Alteration)

More information on the new 2023 Massachusetts Stretch Code can be found here.