Medfield, Massachusetts’ Accessory Dwelling Unit (ADU) Rules

Last updated: 2004

The town of Medfield, MA had the following provisions for Accessory Dwelling Units:

A dwelling unit within a single structure for use by a family member
The house was in existence prior to 1938
The house has a minimum of 2000 sq. ft. of existing floor area
The house meets the lot area requirement for a one-family dwelling in its district
An addition to the house of up to 10% of the existing floor area must be allowed in the rear or side yard, provided the addition is architecturally consistent with the existing house
The exterior of the house must not be altered except for restoration consistent with the existing architecture and exits required by law, which exits must be in the rear or at the side of the house.
The accessory unit must have a minimum floor area of 500 sq. ft., plus 100 sq. ft. for each bedroom over one
The accessory unit must have a bathroom and a kitchen or kitchenette
One off street parking space must be provided for each bedroom in the accessory unit, in addition to spaces required for the existing dwelling
The owner of the house must occupy the house or the accessory unit, except for bona fide temporary absences of up to one year
The Special Permit must be a personal permit restricted to the individual owner-applicant and shall terminate when said owner-applicant ceases to own the dwelling
In the event of a change of ownership of a house for which a Special Permit has been issued for an accessory unit, the new owner or holder of a purchase and sale agreement with the owner may apply for a renewal of the Special Permit.
Special Permit will terminate upon the happening of any of the following events: (a) Sale of the property (b) Death of those persons occupying the Family Apartment, (c) Permanent change of domicile of all of the persons occupying the Family Apartment from said Family Apartment to some other location either within or without the Town of Medfield