ADU rules in Bronx County, NY — also called accessory dwelling unit regulations or granny flat ordinances — cover setbacks, owner-occupancy, parking, and permit requirements.
New York State has not enacted a statewide ADU law. In The Bronx, accessory dwelling units are governed by the NYC Zoning Resolution and require full DOB approval, a Certificate of Occupancy amendment, and compliance with minimum-unit size, egress, and light/air rules.
NYC Zoning Resolution only allows a second dwelling unit if the zoning district permits it (typically R3-2 and higher, or in two-family zones where an accessory unit is permitted). Basement and cellar apartments are historically illegal unless they meet Housing Maintenance Code habitability standards: minimum ceiling height 7 ft, windows in every habitable room, legal egress, and separate heat. The 2024 City of Yes for Housing Opportunity text amendment expanded ADU opportunities in certain R1-R5 districts, but DOB permits and a new C of O are still required. Illegal basement conversions remain a major Bronx enforcement issue.
Illegal conversion: HPD/DOB violations $1,000-$25,000 plus vacate orders. Criminal charges possible if life-safety hazards exist.
Bronx County, NY
Open burning is prohibited in Bronx County under both NYC Fire Code FC 307 and 6 NYCRR Part 215. Burning leaves, brush, trash, or yard waste is illegal year-...
Bronx County, NY
Bronx County is not in a designated wildfire hazard zone. No WUI maps, Cal Fire-equivalent designations, or Chapter 7A-style construction rules apply in NYC.
Bronx County, NY
Bronx County follows NYC Fire Code (Title 29). Open flames and recreational fires are prohibited on terraces, balconies, roofs, and within 10 feet of combust...
Bronx County, NY
Backyard recreational fires are only allowed at 1-2 family homes with private yards, using approved portable fire pits under 3 feet wide. Apartment buildings...
Bronx County, NY
NYC Administrative Code 27-2045 requires working smoke alarms in every dwelling unit. Since 2019 all replacement alarms must be sealed 10-year battery or har...
Bronx County, NY
The Bronx is a dense urban borough with no wildland-urban interface, so there is no defensible space ordinance. Property owners must still maintain lots free...
See how Bronx County's adu rules rules stack up against other locations.
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