Medway, MA

Medway, Massachusetts’ Accessory Dwelling Unit (ADU) Rules

Last updated: 2019

What you need to know:

Medway, like all of Massachusetts since the passage of the 2024 Affordable Homes Act, allows ADUs by right. Each town has slightly different rules surrounding ADUs, but they all must adhere to the framework outlined by the state. The rules for Arlington are outlined below. 

Type of ADU permit required:

ADUs in Medway do not require special permits, and can be built using a traditional building permit. If you have a particularly tight lot, it may be possible to get a special permit to reduce your setbacks.

ADU Rules in Medway:

  • Medway allows ADUs by right in single-family zoning districts.

  • An ADU can be maximum 900 square feet, or half the Gross Floor Area of the main house; whichever is smaller. 

  • ADUs may be attached, detached, or built within the existing house.

  • Short-term rentals of ADUs are not allowed.

  • ADUs must have a separate entrance from the main house - attached ADUs can share an entry hall with the main house, but need a separate entry within the entry hall. 

  • Properties within ½ mile of a transit station do not require additional parking. Properties outside of that area require one additional off-street parking spot for the ADU.  

  • The main house and ADU must be owned by the same person(s). 

Resources:
https://storage.googleapis.com/juniper-media-library/117/2025/10/Zoning%20Bylaw%20Final%20-%20AG%20Approved.pdf (See PDF pages 130-131)

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