Rochester's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Rochester, New York, there are 8 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.

Carport Rules

Rochester's Zoning Code Chapter 120 treats carports as accessory structures. Detached carports must be located in the rear yard, attached carports may also occupy the side yard, and detached accessory structures in R-1, R-2, and R-3 districts require a 10-foot rear yard setback under Article XX (§ 120-163).

Key details: Code Chapter: Zoning Ch. 120. All-District Rule: § 120-163 Accessory Uses. Detached Location: Rear yard only. Attached Location: Side or rear yard. Detached Rear Setback (R-1/R-2/R-3): 10 ft.

Building a detached carport in a front or side yard, encroaching on the 10-foot rear setback, omitting required side yard width in R-1, or constructing before the principal dwelling has zoning compliance can trigger stop-work orders, removal demands, and code enforcement under Chapter 120 and Chapter 90. Adding electrical or enclosing the structure without permits compounds violations.

ADU Owner Occupancy

Rochester's Chapter 120 zoning treatment of ADUs in single-family districts has historically expected the owner to occupy either the principal dwelling or the ADU. Owners receiving ADU pilot program funds must additionally meet program occupancy and rent-restriction conditions for 3 years.

Key details: Code Section: City Code Ch. 120 (Zoning Code). Statewide ADU Mandate: None enacted (A4854 did not pass). Pilot Program Rent Restriction: Fair-market rent for 3 years. Enforcement: Bureau of Buildings and Zoning.

Renting both the primary dwelling and the ADU to unrelated tenants in a single-family district without converting the property to a permitted two-family use is a zoning violation under Chapter 120 and can result in revocation of the certificate of zoning compliance, daily fines, and an order to vacate the second unit. ADU pilot participants who fail to maintain occupancy or fair-market-rent terms may be required to repay city reimbursement.

ADU Rental Restrictions

Rochester allows long-term rental of permitted ADUs subject to Chapter 120 (Zoning) and Chapter 90 (Property Conservation Code) standards. Short-term rentals of an ADU require a city Short-Term Rental Registration ($150/year) and inspection, and pilot-program ADUs must keep rents at fair-market levels for 3 years.

Key details: Long-Term Rental: Permitted with CO and Ch. 90 compliance. Short-Term Rental Registration: $150/year + inspection. State Law: NY Multiple Residence Law; 19 NYCRR Part 1226. Pilot Rent Restriction: Fair-market rent, 3 years. Hotel Tax: Monroe County + NY State sales tax (STR only).

Operating a short-term rental in an ADU without registration and inspection is a violation under the city's STR rules, with fines and possible orders to cease operation. Failure to maintain code compliance under Chapter 90 can result in a notice of violation, fines, and an order to vacate. Pilot-program ADU owners who breach rent or occupancy terms may be required to repay all city reimbursement.

ADU Impact Fees

Rochester does not levy a separate residential impact fee for ADUs. Applicants pay standard building permit fees set by the Bureau of Buildings and Zoning under Chapter 39 of the City Code, and the ADU pilot program reimburses qualifying owners up to $20,000 to offset those fees and other indirect costs.

Key details: ADU-Specific Impact Fee: None. Permit Cost Range: ~$1,000-$4,000. Fee Authority: City Code Ch. 39 (Building Code). Pilot Reimbursement: Up to $20,000. Permit Office Phone: 585-428-6526.

Failure to pay permit fees blocks issuance of the building permit and certificate of occupancy. Constructing an ADU without paying required fees is treated as building without a permit under Chapter 39 and Chapter 120, subject to stop-work order, fines, and possible loss of pilot reimbursement eligibility.

If you are coming from a city with tighter rules, you will find Rochester gives residents more flexibility on adu impact fees.

ADU Permits

Rochester permits accessory dwelling units (ADUs) in residential zones under Chapter 120 (Zoning Code) of the City Code, with a building permit, zoning compliance certificate, and conformance with the 2020 NY State Uniform Code (19 NYCRR Part 1220 et seq.) required. The city operates an ADU pilot program offering reimbursement of city fees and indirect costs up to $20,000.

Key details: Code Section: City Code Ch. 120, Art. XX, § 120-163. State Code: 19 NYCRR Parts 1219-1228 (Uniform Code). Max Accessory Height (R-1/R-2): 15 ft. Permit Office: Bureau of Buildings and Zoning. ADU Pilot Reimbursement: Up to $20,000.

Building an ADU without a permit triggers a stop-work order and a notice of violation from the Bureau of Buildings and Zoning. Penalties under Chapter 39 (Building Code) and Chapter 120 can include daily fines, mandatory removal or legalization, and disqualification from the ADU pilot reimbursement program. Unpermitted occupancy may also draw a NY State Uniform Code citation.

Shed Rules

Rochester regulates accessory structures through the zoning code. Small sheds under 120 square feet may be exempt from building permits. Larger structures require permits and must meet setback requirements. All accessory structures must be in rear or side yards.

Key details: Permit Threshold: 120 sq ft — no permit under. Location: Rear or side yards only. Height: Cannot exceed principal dwelling. Larger Structures: Building permit required.

Unpermitted structures receive a notice to either obtain a retroactive permit (with double fees) or remove the structure within 60 days. Fines of $100–$500 apply for non-compliance.

Garage Conversions

Garage conversions to living space in Rochester require a building permit and must meet NYS Residential Code standards. The property must maintain required off-street parking after the conversion. If creating a separate unit, ADU regulations apply.

Key details: Permit: Building permit required. Code: NYS Residential Code standards. Parking: Must maintain off-street minimums. ADU: Separate unit triggers ADU rules.

Unpermitted garage conversions face fines of $500–$2,000, mandatory permit acquisition (double fees), and may need to be restored to garage use if code requirements cannot be met.

ADU Rules

Rochester has been expanding ADU allowances as part of zoning reform efforts. Accessory dwelling units may be permitted in certain residential districts. ADUs must meet building code standards for habitable space and comply with size and setback requirements.

Key details: Status: Expanding allowances in residential zones. Types: Internal, addition, or detached. Permit: Building permit required. Sale: Cannot be sold separately. Building Code: Full habitable space standards.

Unpermitted ADUs face stop-work orders and removal or legalization requirements. Fines of $500–$2,000 apply for unpermitted construction. Properties with illegal ADUs may face title issues at sale.

The Bottom Line

Rochester's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Rochester is broadly strict or permissive.

Keep in mind that Rochester can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.