Smoke Detector Law New York City apartments, hotels and motels are required to install smoke detectors under a recently enacted law. The local law requires owners of unsprinklered dwellings occupied by more than two families to install at least one smoke detector in each apartment by next Jan. 1, and allows them to charge each tenant no more than $10. Hard-wire detectors are required in new construction and “gut-rehabilitated” apartment buildings. Battery-operated, smoke detectors are permitted in existing buildings and the tenants are required to replace the batteries and maintain the detectors. Hotels and motels must have smoke detectors in rooms or have a smoke detection and fire alarm in all public areas, including corridors.