New Britain, CT Accessory Structures: ADU Rental Restrictions (2026)

New Britain's accessory dwelling unit rules, added by the Common Council on November 20, 2024, let a homeowner build one small second unit on a residential lot, but only on tight conditions: § 270-40-40.290.10.50 requires the unit to be self-contained with its own cooking, sanitary and sleeping space, § 270-40-40.290.10.60 caps it at one bedroom, and § 270-40-40.290.10.90 requires it to connect to and use the principal structure's own utilities and meters rather than getting separate service. Those conditions are built around long-term housing, not nightly rental, and the zoning code says so directly: § 270-40-40.300.60, inside the short-term rental article adopted December 18, 2024, states that accessory dwelling units shall not be used for short-term rentals.

That is an outright prohibition, not a permit or registration step the owner could clear the way a principal dwelling can through a special exception from the Zoning Board of Appeals under § 270-40-40.300.10. An owner who wants to run a short-term rental in New Britain has to do it out of the principal structure, subject to the special exception, annual zoning permit and six-adult occupancy cap that apply there, while the ADU itself stays limited to conventional housing. Because the principal structure and its ADU also share a single street number under § 270-40-40.290.10.100, code enforcement can readily tie a listing back to the address regardless of which structure on the lot is actually being advertised.