Planning board keeps ADU hearing open as counsel clarifies preexisting nonconforming, condo and garage questions

The Southborough Planning Board on Feb. 10 continued its public hearing on a proposed accessory dwelling unit zoning bylaw and implementing regulations while members work through technical questions about how the new state rules intersect with local rules for preexisting nonconforming structures.

Town counsel Jay Talman, who joined the meeting to answer board questions, told the board the ADU law is “a use statute under the Dover Amendment, section 3 of chapter 40A,” and that creates by‑right status for qualifying ADUs but does not change separate statutes that govern dimensional or nonconformity review. “If you have a preexisting nonconforming single‑family house that doesn’t comply with a setback, any addition to that of any kind of size is going to have to get a special permit from the zoning board of appeals,” Talman said.

The discussion focused on several points the board asked counsel to clarify: whether to keep the town’s existing accessory‑apartment special‑permit path while adding a new “protected ADU” bylaw; whether a detached 900‑square‑foot ADU remains by‑right when lot-area or other dimensional controls differ; how gross floor area (GFA) counts items such as basements and garages; and whether towns can restrict ADUs to rental use or bar conversion to condominiums.

Why it matters: Southborough must adopt a local ADU bylaw that complies with recent state regulations. The board and staff want clear, defensible local wording so homeowners understand when an ADU is by‑right, when a special permit is required and how preexisting nonconforming conditions affect approval.

Key points from the meeting

- Protected ADU vs. existing accessory apartments: Counsel advised that the board can either incorporate preferred features from the town’s existing accessory apartment rules into the new ADU section or keep a parallel local provision—“but I would do it in here,” Talman said, recommending a single, compact section with a companion subsection for non‑protected ADUs by special permit.

- Preexisting nonconforming structures: Talman said the state regulations do not override other statutes. “You can’t, through this new statute change what another statute says,” he told the board. The practical effect is that additions to a nonconforming envelope will generally require a special permit from the zoning board of appeals even if the ADU use itself is by‑right.

- Detached vs. attached ADUs and garages: The board asked whether the new rules mean a detached 900‑square‑foot unit could be placed by‑right even where an attached conversion would trigger a special permit. Talman confirmed a detached ADU could be by‑right in some cases, while an attached conversion that alters a nonconforming structure could require a special permit. The board and staff also discussed that the GFA definition in the state regs excludes garages for the principal dwelling calculation but may still count basement area; the exact interpretation can affect whether an ADU hits the 900‑square‑foot cap.

- Accessibility and condoing: Building and public‑health staff had asked whether rental ADUs must be handicap accessible; the building commissioner’s emailed response is that they do not necessarily. The group also asked whether an ADU may be sold as a condominium unit. Talman said town counsel and the Attorney General’s office have not issued a definitive interpretation; he called the question “open” and said some communities take differing positions.

What the board decided and next steps

- The board voted to continue the ADU public hearing to Feb. 20, 2025, to allow counsel and staff to circulate clarified draft language and to give the board time to reconcile the town’s existing accessory‑apartment rules with the new “protected ADU” text.

- Staff will negotiate precise GFA language, confirm how garages and basements are treated in calculations, and seek further AG/EOHLC guidance on the condominium and tenancy questions.

Quote

Town counsel Jay Talman: “The accessory dwelling unit statute … is a use statute under the Dover Amendment, section 3 of chapter 40A,” and “if you have a preexisting nonconforming single‑family house that doesn’t comply with a setback, any addition … is going to have to get a special permit from the zoning board of appeals.”

Ending

The hearing remains open; the board requested a redline of the bylaw that explicitly identifies where local accessory‑apartment provisions will be incorporated or preserved, and asked staff to follow up with the Attorney General’s municipal law unit on the outstanding condo/ownership question.