Shared service and separate controls are different
New York City’s Department of Buildings ADU FAQ says separate utility services are not required, but it also describes distinct controls for systems serving the ADU. Heating, cooling, electrical, and gas systems must have separate controls, disconnects, and shutoffs under the FAQ; water may be shared but needs a separate shutoff. Shared supply therefore does not mean every operational control can be shared.
The FAQ directs applicants to Appendix U and a design professional for the detailed code requirements. Have the project designer determine which configuration and current code provisions apply. Do not use this summary as a utility layout or electrical, gas, heating, or plumbing design.
Match the filing path to the building configuration
The City’s FAQ says ADU filings became available in DOB NOW on September 30, 2025. It distinguishes an Alt-CO-GC job for an ADU within a building from a New Building-GC job for a detached or fire-separated ADU on the same BIN. The building configuration controls the applicable filing route; submitting a job does not establish code compliance or approval.
Confirm the current filing type, Appendix U provisions, zoning and flood-area conditions, and required design documents with DOB and the project professional. Provider capacity, upgrade availability, water or sewer connection permission, and final inspections remain separate questions. For general service-status checks, see ADU electrical service, addressing, and capacity and water, sewer, stormwater, and drainage.