Dunstable, MA
Dunstable, MA Accessory Dwelling Unit (ADU) Rules
City Acceptance Rating: 2/10 (10 is most accepting)
Last updated: 9.13.2024
What You Need To Know
Currently not in compliance with the Massachusetts Affordable Homes Act.
Dunstable requires homeowners to jump through a number of hoops in order to build an ADU. If you have questions about the rules, please contact us. We would be happy to help!
Type of ADU Permit Required
A special permit is required through the zoning board of appeals.
ADU Rules
Except as otherwise provided in these Zoning Bylaws, not more than one accessory dwelling unit may be established on a lot [Amended 5/15/21]. The accessory dwelling unit shall not exceed 35% of the gross living space of the existing or expanded principal structure or 1,200 square feet, whichever is greater, and have no more than two bedrooms. The expansion of an existing structure to accommodate an accessory apartment shall not increase the gross floor space of the existing structure more than 15%.
The accessory dwelling unit may be located in the principal structure or in a detached accessory structure; provided, however, that an accessory dwelling unit may be located in such detached accessory structure only where such detached accessory structure has been in existence for at least ten (10) years. The burden shall be upon the applicant to demonstrate compliance with this subsection.
An accessory apartment shall be a complete dwelling unit with a separate entry, kitchen facilities, at least one bedroom, and a bathroom with sink, toilet and bathing facilities.
The external appearance of the structure in which the accessory dwelling unit is to be located shall not be significantly altered from the appearance of a single family structure or other structure ordinarily used and included in the context of single family dwellings, in accordance with the following:
The expansion of an existing structure to accommodate an accessory apartment shall not increase the gross floor space of the existing structure more than 15%.;
Any stairways or access and egress alterations serving the accessory dwelling unit shall be enclosed, screened, or located so that visibility from public ways is minimized;
Sufficient and appropriate space for at least one (1) additional parking space shall be provided by the owner to serve the accessory dwelling unit. Said parking space shall be constructed of materials consistent with the existing driveway and shall have vehicular access to the driveway;
All construction and/or renovation shall be performed in accordance with the applicable requirements of the State Building Code.
Prior to the conclusion of a Site Plan Review the owner must provide certification, by affidavit, that one of the two dwelling units shall be occupied by the owner of the property as his/her primary residence at least six months in any calendar year. In addition, such owner shall occupy such dwelling unit as his or her primary residence as a condition of the validity of the Special Permit. The owner must also own the entire lot, any structures thereon, and both dwellings.
The initial term and subsequent extensions of a special permit for an accessory dwelling unit shall terminate upon transfer of the ownership of the premises or when the owner no longer occupies the premises as his or her residence in accordance with Section (c) i above. Upon sale or transfer of the property to a new owner, the new owner must submit an affidavit to the Building Inspector of their intention to use one of the dwellings as their primary residence. A subsequent special permit may be granted after certification by affidavit is made by the applicant to the Board of Appeals that the accessory dwelling unit has not been extended, enlarged, or altered to increase its original dimensions, as defined in the initial special permit application.
Use and occupancy of any accessory apartment other than is authorized herein shall be grounds for revocation of any permit granted under this section.
Special Permits for an accessory dwelling unit may be issued by the Board of Appeals upon a finding that the construction and occupancy of the additional dwelling unit complies with foregoing provisions and will not be detrimental to the neighborhood in which the lot is located.
Nothing in this subsection 6.2.1 shall be construed to change or reduce any dimensional or area requirements of this Zoning Bylaw relative to single family dwellings and accessory structures thereto or to allow any uses not otherwise permitted by this Zoning Bylaw, other than accessory apartments as allowed.”