Dartmouth City Zoning Code
ARTICLE 50
Accessory Dwelling Units
§ 375-50.1 Purpose.
The purposes of this Article 50 are:
A.
To provide for housing options for families that reduce maintenance costs and are more affordable than traditional single-family dwellings;
B.
To provide a mechanism for development of a range of housing types and facilities that are responsive to the sociocultural, health care, and recreational needs of residents;
C.
To provide for a type of housing development that reduces the demands on municipal services and assist families;
D.
To use energy, water, and materials more efficiently by increasing the housing supply through concentrated, small-scale development; and
E.
To promote development that is in harmony with the Town's natural features and resources, its historic and traditional landscapes, the existing and probable future use of adjacent land, and the general intent of the Zoning Bylaw;
F.
To establish flexible residential development standards and procedures that will support these objectives; and
G.
To facilitate housing production, diversity, and affordability in the Town's neighborhoods.
§ 375-50.2 Limitations on Use.
Accessory Dwelling Units shall be allowed as-of-right, subject to the following restrictions:
A.
Accessory Dwelling Units shall be allowed only in the following zoning districts: Single Residence A, Single Residence B, Single Residence C and General Residence.
B.
An Accessory Dwelling Unit shall be subordinate to a principal single-family residential structure on the same lot.
D.
Except as provided in § 375-50.2E, all Accessory Dwelling Units shall be attached to a single-family residential structure, through any of the following means:
(1)
Within the existing footprint of the single-family residential structure;
(2)
Within an extension of the footprint of the single-family residential structure, where the appearance of a single-family residential structure is retained; or
(3)
Within a separate structure that creates the appearance of a garage, barn or other structure that is typically subordinate and accessory to a single-family residential use, and that is attached to the single-family residential structure through an interior or exterior breezeway that is not more than 20% of the square footage of the Accessory Dwelling Unit; provided, that the attached structure and breezeway are architecturally compatible with the single-family residential structure by utilizing similar roof style and pitch, roofing material, windows, and siding materials and style.
E.
An Accessory Dwelling Unit may be located within a separate structure on the same lot as a single-family residential structure, where such separate structure remains fully detached, provided that said detached structure meets the following requirements:
(1)
It was in existence on the lot prior to June 6, 2006;
(2)
It complies with current setback, height and lot coverage requirements;
(3)
It is located on a lot that complies with current lot size requirements;
(4)
Its existing first floor footprint is a minimum of 400 square feet;
(5)
Its existing first floor footprint has not been expanded, extended or altered after June 6, 2006.
(6)
Its existing first floor footprint is not expanded, extended or altered in creating the Accessory Dwelling Unit; provided, that nothing shall preclude the detached structure from being completely reconstructed within said footprint; further provided, that any such reconstruction shall ensure that the detached structure is architecturally compatible with the single-family residential structure by utilizing similar roof style and pitch, roofing material, windows, and siding materials and style.
F.
All Accessory Dwelling Units shall comply with the following numerical limits:
(1)
Lots that have more than one residential structure, whether due to variance, preexisting nonconformity or otherwise, are not eligible to have an Accessory Dwelling Unit;
(2)
Only one Accessory Dwelling Unit may be located on a lot; and
(3)
No Accessory Dwelling Unit may be located on any lot on which there exists any accessory apartment or other accessory residential unit, lodging unit or dwelling unit, and whether or not attached to a single-family residential structure, and regardless of how called, that was in existence as of June 4, 2024.
G.
All Accessory Dwelling Units shall comply with the following parking requirements:
(1)
There shall be two off-street parking spaces for an Accessory Dwelling Unit that are in addition to the parking spaces that are required by the underlying zoning district for the single-family residence;
(2)
No on-street parking shall be allowed for Accessory Dwelling Units;
(3)
A single driveway shall serve both the single-family residential structure and the Accessory Dwelling Unit;
(4)
A single parking area shall serve both the single-family residential structure and the Accessory Dwelling Unit; provided, that a detached Accessory Dwelling Unit may have a separate parking area; and
(5)
All parking spaces shall comply with any additional requirements of the underlying zoning district.
H.
All Accessory Dwelling Units are subject to the following occupancy limitations:
(1)
Either the single-family residence or the Accessory Dwelling Unit must be occupied at all times by the owner as the owner's primary residence;
(2)
If the owner is traveling, seasonally living elsewhere or otherwise out of Town, then the owner may not lease, grant a short-term rental for, or otherwise allow the occupancy of, the owner's primary residence;
(3)
The owner may not lease, grant a short-term rental for, or otherwise accept payment for the occupancy of, individual rooms within the Accessory Dwelling Unit or the single-family residence;
(4)
No short-term rental or other occupancy of the Accessory Dwelling Unit or the single-family residence is allowed. Any lease, rental or other occupancy of the Accessory Dwelling Unit and the single-family residence shall solely be for the purpose of establishing residency with the Town;
(5)
A maximum of three persons may occupy the Accessory Dwelling Unit at any given time.
(6)
Except as provided in § 375-50.2H(7), all persons occupying the Accessory Dwelling Unit must be related to each other, and all persons occupying the single- family residence must be related to each other; provided, that the persons occupying the Accessory Dwelling Unit need not be related to the persons occupying the single-family residence.
(7)
Nothing shall preclude either an Accessory Dwelling Unit or a single-family residence from being occupied by one person unrelated to the other occupants, when said unrelated person is a full-time caregiver providing on-site services to one or more of the other occupants.
I.
All other dimensional requirements of the underlying zoning district, including, without limitation, with respect to lot size, lot coverage, building height and setbacks, shall apply to any Accessory Dwelling Unit.
J.
Notwithstanding any other provision in the Zoning Bylaw, no special permit shall be required for installing plumbing in an Accessory Dwelling Unit.
§ 375-50.3 Other requirements.
Nothing in this Article 50 guarantees that a proposed Accessory Dwelling Unit shall satisfy the requirements of the Massachusetts Building Code or any federal, state or local requirements and limitations with respect to sewage, septic systems and potable water. Any Accessory Dwelling Unit must satisfy all such applicable requirements and limitations in order to be in compliance with this Article 50.