Queens County, NY Accessory Structures: ADU Rules (2026)

Accessory Dwelling Unit (ADU) rules in Queens reflect a mix of long-standing restrictions and recent pilot legalization efforts. NYC does not broadly allow detached backyard ADUs the way some states do. In R1 and R2 single-family zones covering much of Eastern Queens (Bayside, Douglaston, Little Neck, Bellerose), a second dwelling unit on the same lot is generally prohibited. R3, R4, R5 districts allow 2-family homes and some multi-family configurations but do not permit adding units beyond the zoning floor-area ratio (FAR). NYC Local Law 126 of 2024, also known as the Basement Apartment Legalization Pilot, authorized legalization of existing basement and cellar apartments in four Queens community districts: CD 10 (Howard Beach, Ozone Park, South Ozone Park), CD 11 (Bayside, Douglaston, Little Neck), CD 12 (Jamaica, Hollis, St. Albans), and CD 13 (Queens Village, Bellerose, Rosedale). The pilot runs through 2030 and allows owners of 1-2 family homes to apply to HPD for Conditional Certificate of No Harassment and legalization. Basement units must meet egress, ceiling-height (minimum 7 feet), and light and ventilation requirements of NYC Building Code and Multiple Dwelling Law. Approximately 100,000 unregulated basement apartments exist citywide, with heavy concentration in Queens neighborhoods. Unauthorized cellar or basement apartments remain illegal and subject to vacate orders outside the pilot. Garage conversions to dwelling units are generally prohibited outside the pilot program. Pilot applicants should consult the NYC HPD Basement Apartment Legalization page.