Madera County, CA Accessory Structures: ADU Rules (2026)

Madera County's zoning code addresses accessory dwelling units (second units) at Section 18.04.153, 'Dwelling, accessory unit,' adopted by Ordinance 525-770 in 2017 to conform to then-Government Code Section 65852.2. As codified, the section allows one ADU per legally created parcel, requires the parcel to be at least one acre with adequate water, sewage disposal, electrical, and drainage, imposes no maximum floor area, allows the unit to be attached or detached with its own kitchen, bathroom, and separate entrance, and requires compliance with the underlying zone's setbacks, lot coverage, and height limits plus parking under Chapter 18.102. The residential development tables in Chapter 18.11 also list 'accessory dwelling unit' as a permitted use (P) in residential zones. Important: California recodified and substantially strengthened ADU law effective January 1, 2025, moving it to Government Code Sections 66310 through 66342. State law now preempts conflicting local rules and requires ministerial (non-discretionary) approval within 60 days, prohibits minimum lot size requirements, mandates allowing at least an 800-square-foot ADU with four-foot side and rear setbacks, and limits parking demands. Where the county's older one-acre and owner-occupancy style limits conflict with state law, the state standards govern. Applicants should confirm current standards with the Madera County Planning Division before relying on the codified text.