Yonkers's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Yonkers, New York, there are 4 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

ADU Rules

Yonkers allows an accessory apartment inside an existing single-family house only if it satisfies a detailed checklist under Section 43-22: one apartment per lot, no more than two bedrooms, located entirely within the principal dwelling, two off-street parking spaces, and full compliance with the district's bulk requirements. Apartments that don't meet every condition are prohibited outright.

Key details: Governing section: Section 43-22, Preexisting accessory apartments. Apartments per lot: One accessory apartment maximum. Bedroom cap: No more than two bedrooms. Parking required: Two off-street spaces. Legalization deadline: 60 days from chapter adoption for unpermitted units.

An accessory apartment that does not meet Section 43-22's conditions, or that was never issued a certificate of occupancy, is prohibited under Section 43-22C and treated as an unpermitted use. Operating one is a Class II offense under the chapter's general enforcement provision, Section 43-153A, punishable by a fine of $100 to $5,000 or up to 15 days in jail under Section 1-21A(2), and the Commissioner of Housing and Buildings can order the illegal unit vacated.

This is one of the stricter rules in Yonkers's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

ADU Rental Restrictions

Yonkers does not allow an accessory apartment to be rented on the open market. Section 43-22 restricts occupancy of any legal accessory apartment, whether pre-existing with a certificate of occupancy or legalized after the fact, to a short list of the owner's relatives: parents, children, grandchildren, siblings, nephews, and nieces.

Key details: Eligible occupants: Parents, children, grandchildren, siblings, nephews, nieces. Governing clauses: Section 43-22A and Section 43-22B(10). Unrelated tenants allowed: No, apartment becomes prohibited. Violation class: Class II offense, Section 43-153A.

Renting an accessory apartment to anyone outside the Section 43-22 relative list voids its legal status and makes it a prohibited use under Section 43-22C. That is enforced as a Class II offense under Section 43-153A, punishable by a fine of $100 to $5,000 or up to 15 days in jail under Section 1-21A(2), and the Commissioner of Housing and Buildings can pursue revocation of the certificate of occupancy for the unit.

This is one of the stricter rules in Yonkers's municipal code. If you are unsure whether your situation complies, it is worth checking with the city before proceeding.

ADU Owner Occupancy

An accessory apartment in Yonkers can only keep its legal status if the property owner actually lives in the main house. Section 43-22 conditions every accessory apartment, whether it already has a certificate of occupancy or is being legalized for the first time, on the lot owner occupying and maintaining the principal dwelling as a primary residence.

Key details: Owner-occupancy source: Section 43-22A and Section 43-22B(5). Who must live on-site: The lot owner, in the principal dwelling. Consequence of moving out: Apartment loses legal status, Section 43-22C. Violation class: Class II offense, Section 43-153A.

An accessory apartment kept in use after the owner stops occupying the principal dwelling as a primary residence loses its Section 43-22 protection and becomes an unlawful use under Section 43-22C. That is a Class II offense under Section 43-153A, carrying a fine of $100 to $5,000 or up to 15 days in jail under Section 1-21A(2), and the Commissioner can move to revoke the certificate of occupancy for the apartment.

This is not one of those rules that cities tend to ignore. Yonkers actively enforces its adu owner occupancy requirements.

Shed & Carport Rules

Yonkers City Code § 43-41O scales shed size to lot area: 100 square feet per 5,000 square feet of lot, with an eight-foot height cap and a five-foot setback from every property line. Only one shed or greenhouse and one playhouse are allowed per lot.

Key details: Max shed size: 100 sq ft per 5,000 sq ft lot. Minimum size floor: At least 100 sq ft. Height cap: 8 feet. Property line setback: 5 feet minimum. Number allowed: 1 shed/greenhouse + 1 playhouse.

A shed that exceeds 100 square feet per 5,000 square feet of lot (or the eight-foot height cap or five-foot setback), or a second shed on the same lot, violates § 43-41O and is a Class II offense under § 43-153: a fine of $100 to $5,000, up to 15 days in jail, or a civil penalty of $250 to $5,000.

The Bottom Line

Yonkers is tougher than many cities when it comes to accessory structures. Out of the 4 rules covered here, 3 are rated strict. If you are a homeowner, renter, or business owner in Yonkers, take the time to understand these requirements before they become a problem. Most violations come with fines, and some repeat violations can escalate.

This guide is based on Yonkers's current municipal code. Local rules can and do change, so check the individual ordinance pages for the latest details, penalties, and FAQs.