ADU Rules in Rochester, NY (2026)
ADU rules, permit requirements, size limits, and fees for Rochester, NY. Source-cited from official municipal code.
Yes, ADUs are allowed in Rochester, NY.
Rochester, NY permits accessory dwelling units (ADUs) on residential properties. ADUs — also called granny flats, in-law units, backyard cottages, or secondary suites — are secondary housing units on a single-family or multifamily lot. State and local law governs the approval process. In Rochester, the Rochester Bureau of Buildings and Zoning handles ADU permit applications. Below you will find the current size limits, setbacks, fees, and timeline for building an ADU in Rochester.
ADU Size Limits
ADU Size Limits in Rochester: Detached ADU: up to 850 sq ft (max height: 20 feet). Attached ADU: 40% of primary dwelling floor area. Rochester allows accessory dwelling units in residential zones per local City Code. Maximum 850 sqft for detached ADUs. JADU is a California-specific concept — not applicable in Rochester.
| Type | Max Size | Max Height |
|---|---|---|
| Detached ADU | 850 sq ft | 20 feet |
| Attached ADU | 40% of primary dwelling floor area | Per zone height limit |
Permit Fees
ADU Permit Fees in Rochester: Plan check fee: $150–$600. Building permit fee: Based on construction value — typically $600–$2,500. Impact fees: None. School fees: None or N/A. Total estimated permit cost: $1,000–$4,000 total permit fees. Rochester does not charge development impact fees for residential ADU projects. Rochester's affordable housing market makes ADU construction economically accessible.
| Fee Type | Amount |
|---|---|
| Plan Check | $150–$600 |
| Building Permit | Based on construction value — typically $600–$2,500 |
| Impact Fees | None |
| School Fees | None |
| Total Estimate | $1,000–$4,000 total permit fees |
Permit Timeline
Rochester ADU Permit Timeline: Rochester Bureau of Planning and Zoning building permit: typically 4-8 weeks for review. Construction 3-9 months. Apply through the Rochester Bureau of Buildings and Zoning online permit portal. Phone: (585) 428-7000.
Setback Requirements
ADU Setback Requirements in Rochester: Front setback: follows zone standard. Side setback: 3 feet. Rear setback: 5 feet. Rochester minimum ADU setbacks: 5 ft rear, 3 ft side. Rochester's older urban neighborhoods have varying lot configurations — many have rear alley access common in early 20th century subdivision patterns.
Parking Requirements
Parking Requirements: 1 off-street parking space per ADU. Near RTS bus routes or major transit corridors, parking may be reduced.
Restrictions & Requirements
- ADU must comply with Rochester City Code accessory use standards
- Only one ADU per single-family lot
- Cannot be separately conveyed from primary lot
- Must maintain minimum lot coverage per zone
- Historic preservation review in Third Ward, Plymouth-Exchange, and other designated districts
How Many ADUs Are Allowed?
Number of ADUs Allowed in Rochester: Single-family lots: 1. Multifamily properties: Multiple units in R-4, R-5, R-M, and commercial zones per development standards. One ADU per single-family lot. Rochester's University of Rochester and RIT student populations create rental housing demand in surrounding neighborhoods.
Single-Family Lots
1
Multifamily Properties
Multiple units in R-4, R-5, R-M, and commercial zones per development standards
Historic District Considerations
Historic District Requirements: Rochester has 9 historic districts where additional design review may be required for ADU construction. Design review approval is required before obtaining a building permit for properties in historic overlay zones. Rochester has notable architectural heritage from its 19th century industrial prosperity. The Third Ward and Corn Hill neighborhoods have well-preserved antebellum and Victorian residential architecture. East Avenue is lined with Gilded Age mansions. George Eastman House (International Museum of Photography and Film) is a National Historic Landmark. The Rochester Landmark Society and local Preservation Board review exterior changes in designated historic districts. Strong Place, Berkshire, and other residential historic districts reflect Rochester's prosperity during the Kodak era. Look up historic district boundaries at: https://www.cityofrochester.gov/preservation
Frequently Asked Questions
Can I build an ADU in Rochester?
Yes. Rochester, NY allows accessory dwelling units. On a single-family lot you can build 1.
How big can an ADU be in Rochester?
The maximum size for a detached ADU in Rochester is 850 square feet.
How long does it take to get an ADU permit in Rochester?
The typical ADU permit timeline in Rochester is Rochester Bureau of Planning and Zoning building permit: typically 4-8 weeks for review. Construction 3-9 months.. Total estimated permit fees are $1,000–$4,000 total permit fees.
Do I need extra parking for an ADU in Rochester?
No, Rochester does not require additional parking for ADUs.
Do I have to live on-site to have an ADU in Rochester?
No, owner-occupancy is not required for ADUs in Rochester.
Source: Rochester City Code Chapter 120 — Zoning; Monroe County Zoning Law. Last verified April 6, 2026. View source