Massachusetts now allows accessory dwelling units by right in single-family zones. Enter your address for an instant feasibility score — what you can build, how big, and what it could be worth.
Free · No signup · Uses public Massachusetts assessor data
A 0–100 feasibility read based on your lot size, home size, and zoning use.
Which ADU types work — interior, attached, or detached — and the max size MA law allows here.
A rough range for rental income and added home value.
Under the Affordable Homes Act, one ADU up to 900 sq ft (or half your home's floor area, whichever is smaller) is allowed by right in single-family zones statewide. Towns can't require owner-occupancy, and can require at most one parking space (none within a half-mile of transit). Towns still set their own setbacks, height, and can restrict short-term rental use. This tool estimates feasibility from public parcel data; local rules and permitting still apply.