Yolo County, CA Accessory Structures: Garage Conversions (2026)

Garage conversions in unincorporated Yolo County are governed by Section 8-2.506(b) of the Zoning Code and by State ADU Law. Section 8-2.506(b)(3)(i) provides that 'no setback shall be required for an existing living area or accessory structure or a structure constructed in the same location and to the same dimensions as an existing structure that is converted to an accessory dwelling unit or a portion of an accessory dwelling unit.' Section 8-2.506(b)(4)(i) directly states that 'parking lost through the conversion of a garage, carport, or covered parking structure is not required to be replaced.' An 'accessory structure conversion' is itself defined in Section 8-2.507 as 'conversion of an existing accessory structure from a non-habitable and non-work use, such as a garage or storage shed, to a habitable or work use such as a second unit or artist studio.' These local provisions are reinforced and, where weaker, superseded by State ADU Law: California Government Code Section 66323 authorizes one converted/attached ADU plus one JADU within a proposed or existing single-family dwelling, and Section 66334 prohibits a parking condition on a JADU even where the JADU is created from an attached garage. Under HCD's December 5, 2025 Letter of Technical Assistance, Yolo County's 2022 ordinance is considered noncompliant with State ADU Law and is therefore 'null and void' under Gov. Code Section 66316, meaning State ADU Law applies directly until a compliant ordinance is adopted. As a result, a homeowner converting a garage to an ADU in Yolo County is entitled to ministerial approval within 60 days (Gov. Code Section 66317), no replacement parking, no fire-sprinkler trigger for a JADU if the primary residence lacks sprinklers (Gov. Code Section 66323(d)), and impact-fee exemption if the ADU is 750 sq ft or less (Gov. Code Section 66311.5).