Albany, NY Accessory Structures: ADU Rules (2026)

Albany rewrote its zoning code in 2017 as the Unified Sustainable Development Ordinance ("USDO"), codified in Chapter 375 of the City of Albany Code. The USDO replaces the older Euclidean zoning ordinance with a form-based and use-based hybrid that explicitly recognizes Accessory Dwelling Units ("ADUs") as an accessory residential use. ADUs are permitted in many of the USDO's residential and mixed-use districts as either an interior conversion (e.g., a basement or attic apartment within the principal dwelling) or an attached/detached accessory structure (e.g., a unit above a detached garage or in a carriage house). The USDO sets standards for accessory uses including a maximum ADU floor area relative to the principal dwelling, a single-unit cap, design and entry standards intended to keep the ADU subordinate to the main building, and treatment of parking and lot coverage. ADU construction requires a building permit from the Department of Buildings & Regulatory Compliance, plan review against the NY State Uniform Fire Prevention and Building Code (egress, fire separation, smoke and CO alarms, electrical, plumbing, mechanical), and — when the ADU is rented out — a Residential Occupancy Permit under Chapter 231. The specific list of districts in which an ADU is allowed by right vs. requires a special permit or site-plan review, along with the size and design standards, is set out in the USDO use tables and the article governing accessory uses; applicants should confirm the current standards with the Department of Planning & Development.