What is an Accessory Dwelling Unit?

An accessory dwelling unit or ADU is a small residential living space located on the same lot as another home.

What is the policy on ADUs?

The new ADU policy recently signed by the governor allows property owners to build an ADU without having to get special or discretionary approval from the local zoning board. The full law is outlined in Section 8 of Chapter 150 of the Acts of 2024.

What does an ADU need to be considered an ADU?

• An ADU must maintain a separate entrance, either directly from the outside or through an entry hall or corridor shared with the principal dwelling
• An ADU must be either no larger than half the gross floor area of the principle dwelling or 900 square feet (whichever is smaller)
• An ADU must meet local municipal restrictions, including, but not limited to, additional size restrictions and/or restrictions or prohibitions on short-term rental

Roles of the municipality:

Municipalities may impose reasonable restrictions and requirements for:

• Site Plan Review
• Title V Requirements
• Regulations concerning dimensional setbacks and the bulk and height of structures
• Short-term rentals

Review Frequently Asked Questions answered by the State

Frequently Asked Questions Related to Septic Systems and ADUs