Accessory Structures in Union City, CA (2026)
6 verified accessory structures rules for Union City, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Union City must approve or deny a complete ADU or JADU permit application within 60 days and cannot require a hearing or discretionary review: miss the deadline and the application is automatically approved.
Union City ADU Permit Process
Some RestrictionsUnion City Municipal Code § 18.34.020(B)
A permit application for an ADU and/or JADU shall be processed ministerially, without discretionary review or a hearing. 2. Review Period. a. Developed Lot. If there is an existing single-family or multifamily dwelling on a lot, a permit application for an ADU and/or JADU shall either be denied or approved within 60 days of receipt of a complete application. b. Undeveloped Lot. If a pe...
ADU Impact Fees
Union City charges impact fees on accessory dwelling units of 750 square feet or larger, prorated to the ADU's share of the primary home's square footage; smaller ADUs are fee-exempt.
Union City ADU Impact Fees
Some RestrictionsUnion City Municipal Code § 18.34.030(F)
ADUs that are 750 square feet or larger shall be subject to all applicable impact fees. Impact fees shall be charged proportionally in relation to the square footage of the primary dwelling unit. As ascribed in Government Code Section 66324, as the same may be amended from time to time, and reprinted here for reference, "impact fee" means: A "fee" as defined in subdivision (b) of [Government C...
ADU Owner Occupancy
Union City exempts ADUs from owner-occupancy under state law, but a junior ADU (JADU) still requires the owner to live in either the main house or the JADU itself.
Union City JADU Owner-Occupancy Rule
Some RestrictionsUnion City Municipal Code § 18.34.040(D)
Owner Occupancy. JADUs shall be subject to owner-occupancy either in the remaining portion of the single-family residence or the newly created JADU. Owner occupancy shall not be required if the owner is another governmental agency, land trust, or housing organization. E. Deed Restriction. A recordation of a deed restriction, which shall run with the land, shall be filed with the City. The de...
ADU Rental Restrictions
Union City bans renting an accessory dwelling unit for less than 30 days, closing the door on Airbnb-style short-term rentals for every ADU permitted under the city's zoning code.
Union City ADU Short-Term Rental Ban
Heavy RestrictionsUnion City Municipal Code § 18.34.030(J)
Short-Term Rental Limitation. ADUs shall not be rented for a term of less than 30 days. K. Utility Connection. ADUs constructed within the proposed space of a primary dwelling or existing space of a primary dwelling unit or accessory structure shall not be required to install a new or separate utility connection directly between the ADU and the utility or impose a related connection fee or c...
Shed & Carport Rules
Union City treats carports as accessory structures requiring specific yard setbacks, corner-lot clearance, and site development review once combined accessory square footage tops 450 square feet.
Union City Carport Setback Rules
Some RestrictionsUnion City Municipal Code § 18.32.020(I)
On a corner site, garages and carports which are entered perpendicular to and from across the side lot line adjoining the street shall be located not closer than 20 feet to such lot line. ... Detached accessory structures shall be located not closer than five feet from any other structure, four feet to a side or rear lot line.
Garage Conversions
Union City's ADU ordinance lets homeowners convert an attached or detached garage into an accessory dwelling unit, waiving replacement parking and combining the garage demolition permit with the ADU permit review.
Union City Garage-to-ADU Conversion
Light RestrictionsUnion City Municipal Code § 18.34.030(B), (C)(5)
ADUs shall be either attached to, or located within, the proposed or existing primary dwelling, including attached garages, storage areas or similar uses or an accessory structure or detached from the proposed or existing primary dwelling and located on the same lot as the proposed or existing primary dwelling, including detached garages. ... replacement parking shall not be required when a gar...
Looking for Alameda County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Union City city rules.
Accessory Structures in Alameda County →