ADU Rules in Yonkers, New York

Yonkers is the largest city in Westchester County and New York State's fourth-largest city overall, perched on the Hudson River immediately north of the Bronx. Its character is distinctly urban — dense, walkable neighborhoods near the waterfront, more suburban hills to the north and east — making it a unique transitional zone between the outer NYC boroughs and the broader Westchester suburbs. This complexity is reflected in its ADU regulations.

2024 New York State Housing Legislation

The 2024 New York State housing legislation introduced by Governor Hochul specifically targeted exclusionary suburbs, many of which surround Yonkers in Westchester County. While Yonkers itself is a city — not a suburban village — it faces the same regional housing pressure. The legislation created incentives for municipalities to permit more housing, including ADUs. Yonkers property owners benefit from being in a city that generally has broader housing permissions than surrounding Westchester suburbs.

ADU Regulations in Yonkers

Yonkers' Zoning Ordinance governs ADUs under its accessory apartment provisions. Key considerations:

• Zoning districts: Yonkers has a range of residential districts from low-density single-family to dense multi-family. ADU permissions vary by district — single-family districts near the northern part of the city may have different (often more restrictive) rules than the dense southwest near the NYC border
• Attached ADUs: Basement conversions and internal unit splits may be possible in one- and two-family homes in appropriate districts
• Detached ADUs: The dense urban fabric of much of Yonkers limits opportunity for detached backyard cottages, but properties in the hillier northern areas may have more lot area available
• Owner occupancy: May be required as a condition of accessory apartment approval in certain districts
• Parking: Yonkers requires parking analysis as part of ADU review given its congested streets; Metro-North proximity in some areas may reduce parking requirements

Hudson River Waterfront Considerations

The western portion of Yonkers along the Hudson River includes the Yonkers waterfront redevelopment zone. Properties near the river may be subject to New York State Department of Environmental Conservation (DEC) waterfront regulations, tidal wetlands rules, and FEMA flood zone requirements. Any ADU project near the waterfront requires additional regulatory due diligence.

NYC Proximity and Market Context

Yonkers' proximity to the Bronx and Midtown Manhattan — with Metro-North Commuter Rail service — drives very high rental demand. The ADU rental market is robust, making ADU investment financially attractive. However, property owners renting ADUs must comply with all applicable New York State landlord-tenant laws, including required lease provisions, security deposit rules, and Westchester County Fair Housing ordinances.

Permit Process

1. Verify zoning district and ADU permissions via Yonkers GIS or the Planning and Development Department
2. Submit a pre-application inquiry or attend a pre-submission meeting
3. Prepare construction documents with a licensed architect or engineer
4. File building permit application with the Department of Housing and Buildings
5. Complete zoning review and any required Board of Zoning Appeals (BZA) approval if non-conforming
6. Pass all required inspections and receive Certificate of Occupancy

Yonkers Planning and Development Department: yonkersny.gov/planning Yonkers Department of Housing and Buildings: yonkersny.gov/housing-buildings

Disclaimer: Zoning regulations and ADU rules are subject to change. This page is for informational purposes only. Verify all current requirements with the City of Yonkers Planning and Development Department and Department of Housing and Buildings before proceeding.