Accessory Dwelling Units

Dated: March 11 2025

Views: 1073

ADU: Accessory dwelling units are now permitted statewide in Massachusetts.

Sometimes called tiny homes or in-law suites, ADUs are small, independent living spaces located on the same lot as a principal dwelling in a single-family residential zoning district. Garages, attics, and basements can be converted into ADUs, or an ADU can be a newly constructed detached cottage or addition onto the primary home, with a separate entrance.

As of Sunday, Feb. 2 2025,
ADUs less than 900 square feet can be built by-right in single-family zoning districts statewide.

Residents interested in developing an ADU should contact their city to apply for a permit.

The maximum size of an ADU is no more than half of the gross floor area of the principal dwelling, or 900 square feet, whichever is smaller.

An ADU must:  

  • Maintain a separate entrance, either directly from the outside or through an entry hall or corridor shared with the principal dwelling sufficient to meet the requirements of the state building code for safe egress;
  • Be either no larger than half the gross floor area of the principal dwelling or 900 square feet, whichever is smaller;
  • Meet local municipal restrictions, including, but not limited to, additional size restrictions and/or restrictions or prohibitions on short-term rental if the city or town decides to impose these.

For more information click below.

https://www.mass.gov/info-details/accessory-dwelling-units#what-is-the-law?-

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Sharon Lucido

Both my Dad and my Father-in-law were Real Estate Brokers. From watching them, I learned that real estate is not just about buying and selling, it's an emotional process that should be handled with ho....

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