ADU Regulations in Tuolumne County, California (2026)

Regulations at a glance

Local rules & notes

Standardized ADU Building Plans: The County implementation program includes the creation of standardized building plans to encourage ADU construction and reduce costs for homeowners. Generous Maximum Size: The County allows both attached and detached ADUs to reach 1,200 square feet, which is significantly higher than the state-mandated minimum of 850/1,000 square feet. Impact Fee Waiver for Affordable Units: The County Services Impact Mitigation Fee is waived for units serving extremely low to median-income households.

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

Frequently asked questions about ADU regulations in Tuolumne County

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

  In Tuolumne 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; Tuolumne County may follow state defaults or have local limits. Verify with Tuolumne County planning for your specific lot.

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

  In Tuolumne 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 Tuolumne County planning for overlay zones or design standards that could affect your site.

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

  In Tuolumne 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 Tuolumne County or county planning for your zone.

• Is ADU approval ministerial in Tuolumne County?

  In Tuolumne 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; Tuolumne County planning can confirm the exact process.

• Are there parking requirements for ADUs in Tuolumne County?

  In Tuolumne 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 Tuolumne County planning for your address.