ADU Regulations in MA — Backyard ADUs

Fitchburg, MA

Attached ADU, Convert Existing SpaceChris LeeSeptember 5, 2024Western MA, Massachusetts, Fitchburg, Friendliness Score 7/10

Nantucket, MA

Convert Existing Space, Attached ADUChris LeeAugust 20, 2024Cape Cod, Massachusetts, Nantucket

Pembroke, MA

Convert Existing Space, Attached ADU, Detached ADUChris LeeAugust 20, 2024Massachusetts, Greater Boston, Pembroke, Friendliness Score 2/10

Northborough, MA

Convert Existing Space, Attached ADU, Detached ADUChris LeeAugust 20, 2024Massachusetts, Northborough, Greater Boston, Friendliness Score 7/10

Duxbury, MA

Convert Existing SpaceChris LeeAugust 20, 2024Massachusetts, Cape Cod, Duxbury, Friendliness score 4/10

Marshfield, MA

Convert Existing Space, Detached ADU, Attached ADUChris LeeAugust 20, 2024Cape Cod, Massachusetts, Marshfield, Friendliness score 4/10

Plymouth, MA

Attached ADU, Detached ADU, Convert Existing SpaceChris LeeAugust 20, 2024Massachusetts, Cape Cod, Plymouth, Friendliness Score 9/10

Beverly, MA

Convert Existing Space, Attached ADU, Detached ADUChris LeeJuly 9, 2024Beverly, Massachusetts, Greater Boston, Friendliness Score 9/10

Swampscott, MA

Attached ADU, Convert Existing Space, Detached ADUChris LeeJuly 9, 2024Greater Boston, Swampscott, Massachusetts, Friendliness Score 8/10

Arlington, MA

Convert Existing Space, Attached ADU, Detached ADUChris LeeJuly 9, 2024Greater Boston, Arlington, Massachusetts, Friendliness Score 8/10

Lancaster, MA

Attached ADU, Convert Existing Space, Detached ADUChris LeeApril 25, 2024Friendliness Score N/A, Lancaster, Massachusetts, Western MA

Medway, MA

Convert Existing Space, Attached ADU, Detached ADUGuest UserFebruary 18, 2022Friendliness Score N/A, Medway, Massachusetts, Greater Boston

Medfield, MA

Convert Existing SpaceGuest UserFebruary 18, 2022Friendliness Score N/A, Greater Boston, Medfield, Massachusetts

Lexington, MA

Attached ADU, Convert Existing Space, Detached ADUGuest UserFebruary 18, 2022Greater Boston, Friendliness Score: 7/10, Massachusetts, Lexington

Cambridge, MA

Attached ADU, Convert Existing Space, Detached ADUGuest UserFebruary 17, 2022Greater Boston, Friendliness score 10/10, Cambridge, Massachusetts

Lincoln, MA

Attached ADU, Convert Existing SpaceGuest UserFebruary 17, 2022Greater Boston, Friendliness score 10/10, Lincoln, Massachusetts

Newton, MA

Attached ADU, Convert Existing SpaceGuest UserFebruary 17, 2022Greater Boston, Friendliness score 10/10, Newton, Massachusetts

Concord, MA

Concord, MA allows ADUs up to 750 sq. ft. by right.

Attached ADU, Convert Existing SpaceGuest UserFebruary 7, 2022Greater Boston, Friendliness Score 7/10, Concord, Massachusetts

Williamsburg, MA

Williamsburg does not allow detached accessory dwelling units (ADUs). Granny flats must be constructed within existing space or as an addition.

Attached ADU, Convert Existing SpaceGuest UserJune 29, 2021Friendliness Score N/A, Western MA, Massachusetts, Williamsburg

Sandwich, MA

Sandwich draws a distinction between “Accessory Dwelling Units” and “Accessory Apartments” and provide different rules for each.

Convert Existing Space, Attached ADUGuest UserSeptember 11, 2020Friendliness score 4/10, Sandwich MA, Sandwich, Massachusetts, Cape Cod