The Zoning and Planning Committee set a public hearing for the second meeting in February to consider amendments to Newton’s accessory dwelling unit (ADU) ordinance to comply with the state Affordable Homes Act and draft regulations.

Planning staff explained that many of Newton’s ADU rules already align with the state changes. Key required updates described by staff include: removing owner-occupancy requirements for ADU units, conforming ADU dimensional controls to the state’s definition of gross floor area (rather than local ‘‘habitable area’’), permitting separate exterior entrances where the state definition allows, and adjusting size calculations so internal ADUs are measured as up to 50% of the principal dwelling’s gross floor area (but capped at 1,000 square feet by right). Staff said special-permit thresholds would remain (1200 sq. ft. was cited as an upper limit under special permit in staff’s proposal).

Staff recommended postponing a final vote until state regulations are finalized so the city can use clean, consistent language. Committee members asked numerous clarifying questions about how gross floor area will be measured (attic/basement inclusion), whether FAR and other local dimensional controls will still apply, the handling of historic carriage houses, enforcement implications (including short-term rental prohibitions), and whether owner-occupancy covenants should be retained for enforcement and to curb short-term rental conversions.

The committee also agreed to open a parallel track for separate, locally proposed ADU amendments not required by state law (for example, rules addressing occupancy counts, additional design incentives, carriage-house flexibility). Those suggested amendments will be docketed as a separate item so committee members can develop and vet them before including them in a public hearing package. The committee’s motion to set the public hearing and permit a parallel amendments docket passed by voice vote.