Yonkers's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Yonkers, New York, there are 9 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.

Tiny Homes

Tiny homes on foundations in Yonkers are regulated as ADUs or primary dwellings under Zoning Ch. 43. Tiny homes on wheels (RVs) cannot be used as permanent residences in residential zones.

Key details: On Foundation: NYS Res. Code Appx Q. On Wheels: Not permanent residence. Min Dwelling Size: Per zoning district. ADU Path: Accessory apt rules apply.

Illegal residential use of RV: zoning fines plus occupancy notices. On-foundation tiny homes lacking permits: stop-work orders and demolition possible.

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.

Carport Rules

Carports in Yonkers are treated as accessory structures requiring building permits and conformance with zoning setbacks. Must be anchored, meet wind-load requirements, and respect side/rear setback minimums.

Key details: Permit: Required for permanent. Setbacks: 3-5 ft side/rear typical. Wind Load: NYS code compliance. Fabric Carports: Often prohibited.

Unpermitted carport: zoning fines $100-$500; removal ordered for setback or anchoring violations.

ADU Permits

Yonkers regulates accessory dwelling units as 'accessory apartments' under Chapter 43 (Zoning) of the City Code, with supplemental standards in Article VI (Sections 43-40 and 43-41). Accessory apartments are an Article VII special use requiring Planning Board review and approval. A building permit and a separate certificate of occupancy must be issued by the Department of Housing and Buildings before lawful occupancy.

Key details: Governing Code: Yonkers Zoning Ch. 43, Art. VI/VII. Permit Track: Planning Board special use permit. Unit Limit: 1 accessory apartment per lot. Bedroom Cap: 2 bedrooms maximum. Parking: 2 off-street spaces minimum.

Building or occupying an accessory apartment without a Planning Board special use approval, building permit, and certificate of occupancy violates Chapter 43 and the New York State Uniform Code. The Department of Housing and Buildings can issue stop-work orders, civil penalties, and orders to vacate. Code Enforcement may refer cases to the Corporation Counsel for prosecution under Article XII. Unpermitted electrical, plumbing, or gas work commonly voids homeowner insurance and creates life-safety risk for occupants.

Compared to other cities, Yonkers takes a harder line on adu permits. The enforcement and penalty structure reflects that.

ADU Rental Restrictions

Yonkers accessory apartments may not be operated as short-term rentals (under 30 days) and may not be leased to non-relatives even on long-term terms. Chapter 43 limits occupancy to relatives of the lot owner or spouse. New York State Multiple Dwelling Law generally prohibits rentals of less than 30 days in Class A multiple dwellings statewide, and the 2024 statewide STR registry law adds tax-collection obligations through booking platforms.

Key details: Short-Term Rentals: Not allowed (<30 days). Non-Relative Long-Term Lease: Not allowed. State Law: NY Multiple Dwelling Law. Statewide STR Registry: 2024 law - effective 2025. Westchester Tax Rate: ~8-9% occupancy/sales tax.

Listing a Yonkers accessory apartment on Airbnb, Vrbo, Booking.com, or similar platforms violates Chapter 43's occupancy restrictions and may also violate the New York State Multiple Dwelling Law and the statewide STR registry law. Penalties include civil fines, orders to cease the listing, and revocation of the accessory apartment's certificate of occupancy. Booking platforms are required to remove non-compliant listings on notice and must remit occupancy tax collected.

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

Yonkers requires that the property owner occupy and maintain the principal dwelling building on the lot as their primary residence. The accessory apartment itself may only be occupied by relatives of the lot owner or the owner's spouse - including children, grandchildren, parents, siblings, nephews, and nieces. Non-relative tenants are not permitted under the current Chapter 43 supplemental regulations.

Key details: Owner Must Live On-Site: Yes - in principal dwelling. Permitted Occupants: Relatives of owner or spouse. Non-Relative Tenants: Not permitted. Citation: Yonkers Code Ch. 43 (Art. VI 43-40/41). Transfer on Sale: Authorization does not run with land.

Renting an accessory apartment to a non-relative or operating the lot without the owner as primary resident violates Chapter 43 and exposes the owner to revocation of the certificate of occupancy, civil penalties, and orders to vacate the accessory unit. Sale of the property generally voids the accessory apartment authorization unless the new owner reapplies and satisfies the supplemental standards. Concealing occupancy facts on permit applications can support criminal misdemeanor referrals under Article XII.

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

ADU Impact Fees

Yonkers does not impose a dedicated impact fee on accessory apartments. Applicants pay the standard Chapter 43 special use permit application fee plus building permit fees set by the Department of Housing and Buildings fee schedule. The published fee for accessory residential uses or structures for single- and two-family uses is $175 at the special use stage, with building, plumbing, electrical, and certificate of occupancy fees additional.

Key details: Dedicated ADU Impact Fee: None in Yonkers. Special Use Fee: $175 (accessory residential 1-2 family). Building Permit Basis: Construction valuation. County Impact Fee: None imposed by Westchester. Authority: Yonkers Dept. of Housing and Buildings.

Failure to pay required special use, building, or trade permit fees prevents permit issuance, blocks the certificate of occupancy, and exposes the owner to enforcement under Article XII of Chapter 43. Unpaid water or sewer connection charges can result in service refusal by DPW or by the county sewer district.

The rules around adu impact fees in Yonkers lean permissive, but that does not mean anything goes.

Garage Conversions

Converting a garage to living space in Yonkers requires building permits, compliance with residential code (egress, insulation, heat, ventilation), and typically replacement of required off-street parking.

Key details: Permit: Building + zoning required. Parking Replacement: Usually required. Code Requirements: NYS Res. Code applies. ADU Conversion: Accessory apt. rules apply.

Unpermitted conversions: stop-work, double fees, zoning fines, forced restoration. Uncovered conversions often surface during real estate transactions.

Compared to other cities, Yonkers takes a harder line on garage conversions. The enforcement and penalty structure reflects that.

ADU Rules

Yonkers permits accessory dwelling units in specified residential districts subject to owner-occupancy, off-street parking, and setback requirements under Zoning Ordinance Chapter 43. NY has no statewide ADU preemption.

Key details: Authority: Yonkers Zoning Ch. 43. Owner-occupancy: Required. Parking: Extra off-street space. State Law: No NY preemption. Grants: NY 'Plus One ADU' available.

Illegal ADU conversions: zoning violations $250-$1,000 plus required restoration. Code compliance costs recoverable from owner.

Shed Rules

Sheds in Yonkers under 100-144 sq ft (per zoning district) may be exempt from building permits but must meet setback rules. Larger sheds require Building Department permits.

Key details: Permit Exempt: Under ~100-144 sq ft. Side/Rear Setback: 3-5 ft typical. Front Yard: Not allowed. Max Height: 12-15 ft typical. Electrical: Separate permit.

Non-compliant shed: zoning citation $100-$500; may require relocation or removal at owner expense.

The Bottom Line

Yonkers is tougher than many cities when it comes to accessory structures. Out of the 9 rules covered here, 5 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.