Pursuant to the Affordable Homes Act (Chapter 150 of the Acts of 2024), the Town of Nantucket now allows for the construction of Accessory Dwelling Units, or ADUs, by-right in any zoning district that permits single-family homes. However, this allowance has raised concerns that, in certain zoning districts, a property which has a Primary, Secondary, and Tertiary Dwelling may also apply for a fourth dwelling by-right under the Zoning Bylaw, resulting in four units on a single lot. It also acts as a disincentive for the creation of additional affordable tertiary dwellings as the ADUs are allowed by-right, without the need for a special permit.
As a result, a temporary moratorium on tertiary dwellings was approved at Nantucket’s 2025 Annual Town Meeting. This moratorium will allow the Town to take the time to carefully review the definitions and requirements for Secondary and Tertiary Dwellings and make any necessary amendments to prevent any unintended consequences of this new law.