Advisory Committee backs ADU bylaw change to align town code with state law

The Town of Southborough Advisory Committee voted unanimously Wednesday to support Article 9 on the warrant for the upcoming town meeting, an update to the town’s accessory dwelling unit (ADU) bylaw presented by members of the Planning Board.

The Planning Board presentation said the proposed changes bring the town bylaw into harmony with Massachusetts General Laws while retaining the town’s special-permit review for ADUs that exceed the state’s by-right thresholds. The advisory committee voted, by roll call, 5-0 to submit Article 9 in the current warrant.

The presentation, led by Planning Board member Marnie, said the article replaces the town’s older terminology and definition of “accessory apartment” with the state definition of an ADU, clarifies that mobile homes and travel trailers are excluded, removes ADU allowances from the Industrial Park (IP) district, and inserts the state ADU by-right requirements into all other zoning districts. The Planning Board proposed keeping the town’s special-permit procedure for units that exceed the state’s by-right thresholds—described during the presentation as 900 square feet or one-half of the gross floor area of the principal dwelling, whichever is greater.

Marnie told the committee the package also removes a local cap that had limited ADUs to 5% of housing units, and that the town’s incentives for adaptive reuse of historic buildings would remain intact. "It will update the language to be in harmony with the state," Marnie said, adding, "Please vote yes on Article 9." The presentation materials and a one-page handout will be available at town meeting, she said.

Advisory members asked procedural questions about where special-permit applications would be heard. Howard asked whether special permits go to the Zoning Board or the Planning Board; Marnie and others clarified that, under the proposed changes, special permits for ADUs would continue to follow the existing process and be handled by the Zoning Board, though some other types of special permits in downtown and business-village districts have been updated elsewhere in the code to go to the Planning Board.

The advisory committee then voted to submit Article 9. The motion on the floor was recorded as "I move to submit Article 9 in the current warrant." A roll-call vote followed: Andrew, Tim, Howard, Eric and Marcy each recorded "Aye." The motion passed unanimously.

The Planning Board requested Advisory’s support so that the board’s recommendation would appear in Advisory’s warrant letter to voters. The Planning Board said the changes are primarily administrative cleanup to reflect the state statutory ADU framework while preserving local review for larger units.

Article 9 will appear on the town meeting warrant with Advisory’s recommendation to support. Planning Board members said they will provide the handout and a concise presentation at town meeting rather than going through the full annotated draft on the floor.

Notes: The Planning Board presentation repeatedly referenced aligning the bylaw with state law; the presentation materials will be included with warrant documents at town meeting.