ADU Rules in New York City, NY (2026)
ADU rules, permit requirements, size limits, and fees for New York City, NY. Source-cited from official municipal code.
Whether ADUs are allowed in New York City, NY has not been confirmed — see the official source before proceeding.
Whether New York City, NY permits accessory dwelling units (ADUs) has not been confirmed from an official source. ADUs — also called granny flats, in-law units, or secondary suites — are secondary housing units on a single-family or multifamily lot. Contact the local building department through their official website to verify current ADU rules before proceeding, as regulations may have changed since this data was last reviewed.
ADU Size Limits
ADU Size Limits in New York City: Detached ADU: size varies by zoning — see official source (max height: varies — see official source). Attached ADU: size varies by zoning — see official source.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | See official source | See official source |
| Attached ADU | See official source | See official source |
Permit Fees
ADU Permit Fees in New York City: Plan check fee: Varies. Building permit fee: Varies. Impact fees: None. School fees: None or N/A. Total estimated permit cost: Varies.
| Fee Type | Amount |
|---|---|
| Plan Check | Plan examination fee varies by construction cost — approximately $200–$2,500 |
| Building Permit | Filing fee plus construction cost percentage — typically $500–$5,000 |
| Impact Fees | None |
| School Fees | None |
| Total Estimate | See official source |
Permit Timeline
New York City ADU Permit Timeline: Permit timeline has not been confirmed — contact the department for current processing times. Apply through the local building department online permit portal. Contact them through their official website for current contact information.
Setback Requirements
ADU Setback Requirements in New York City: Front setback: follows zone standard. Side setback: no minimum. Rear setback: no minimum.
Parking Requirements
Parking Requirements: Parking requirements have not been confirmed — see official source.
Restrictions & Requirements
- Owner must reside on property as primary residence
- ADU must comply with NYC Building Code habitability standards
- Basement/cellar ADUs must meet ceiling height minimums (7 ft minimum in habitable rooms)
- Fire safety and egress requirements must be met
- Landmark designation or historic district designation may limit alterations
- Rent stabilization may apply to new rental units in buildings with 6+ units
How Many ADUs Are Allowed?
Number of ADUs Allowed in New York City: Single-family lots: not confirmed — see official source. Multifamily properties: not confirmed — see official source.
- Single-Family Lots
- 1 ADU per 1-family dwelling lot
- Multifamily Properties
- 1 ADU per existing unit for conversions; site-specific for new construction
Statewide Preemption
ADU Preemption
We could not confirm a statewide ADU preemption statute for New York.
View New York preemption detailsFrequently Asked Questions
Can I build an ADU in New York City?
Yes. New York City, NY allows accessory dwelling units. On a single-family lot you can build 1 ADU per 1-family dwelling lot.
How big can an ADU be in New York City?
The maximum size for a detached ADU in New York City is 1,200 square feet.
How long does it take to get an ADU permit in New York City?
The typical ADU permit timeline in New York City is NYC DOB permits typically 3-6 months for plan examination. Expedited review available through NYC Development Hub. Construction 6-18 months. ADU Express program in development as of 2025.. Total estimated permit fees are $1,000–$8,000 total permit fees.
Do I need extra parking for an ADU in New York City?
New York City parking rules for ADUs: Parking requirements for ADUs waived citywide under City of Yes for Housing Opportunity (effective September 30, 2025). Previously ADUs in some districts required 1 additional space.
Do I have to live on-site to have an ADU in New York City?
Owner-occupancy requirement in New York City: Owner-occupancy of primary residence required for ADU in 1- and 2-family homes under City of Yes framework. Property owner must maintain primary residence on lot.
Source: NYC Zoning Resolution Article II; City of Yes for Housing Opportunity Text Amendment (approved December 2024). Last verified April 3, 2026. View source