ADU Regulations in Fresno County, California (2026)

Regulations at a glance

Local rules & notes

Low Water Area Prohibition: ADUs are strictly prohibited in designated 'low water areas'. Property owners must verify their status via the Zoning department or online GIS map. Separate Septic Requirement: If the primary residence uses a septic system, the ADU is required to have a completely separate septic system installed, rather than sharing the existing one. Pre-Approved Plans: The County offers pre-approved building plans to applicants, though site-specific factors like orientation and utilities still apply.

For the official ordinance and latest updates, check your city or county planning department.

Frequently asked questions about ADU regulations in Fresno County

• What is the maximum ADU size in Fresno County, California?

  In Fresno County, the maximum ADU size is typically 1200 square feet, depending on whether the unit is attached or detached. California state law allows up to 1,200 sq ft for detached ADUs and 800 sq ft for attached in many jurisdictions; Fresno County may follow state defaults or have local limits. Verify with Fresno County planning for your specific lot.

• What are the setback requirements for ADUs in Fresno County?

  In Fresno County, typical setback requirements are 4 feet from the side property line and 4 feet from the rear. These may be reduced to 4 feet under California Government Code § 65852.2 where applicable. Check with Fresno County planning for overlay zones or design standards that could affect your site.

• What is the maximum height for an ADU in Fresno County?

  In Fresno County, the maximum height for an ADU is generally 16 feet. State law often allows up to 16 feet for detached ADUs and up to 25 feet when within 4 feet of the property line in some cases. Confirm with Fresno County or county planning for your zone.

• Is ADU approval ministerial in Fresno County?

  In Fresno County, ADU approval is typically Ministerial (by-right) per Gov Code §65852.2. Ministerial (by-right) review means the city must approve qualifying applications without discretionary review, per California Gov Code § 65852.2. Your project must still meet objective standards; Fresno County planning can confirm the exact process.

• Are there parking requirements for ADUs in Fresno County?

  In Fresno County, parking for ADUs is generally Often waived per state law; check local ordinance. California law often waives parking for ADUs within a half-mile of transit or in certain historic districts. Check with Fresno County planning for your address.