ADU Regulations in Claremont, California (2026)

Regulations at a glance

Local rules & notes

Prohibition on Over-Garage Construction: The city explicitly prohibits constructing an ADU over a garage space, which is a significant restriction limiting second-story ADU potential. Plate Height Matching Requirement: The plate height of the ADU cannot exceed the plate height of the primary dwelling, potentially forcing lower ceiling heights or specific roof designs. Specific Fee Estimates: The document provides concrete dollar ranges for grading and engineering fees, which is rare for a zoning summary.

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

Frequently asked questions about ADU regulations in Claremont

• What is the maximum ADU size in Claremont, California?

  In Claremont, the maximum ADU size is typically 1000 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; Claremont may follow state defaults or have local limits. Verify with Claremont planning for your specific lot.

• What are the setback requirements for ADUs in Claremont?

  In Claremont, 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 Claremont planning for overlay zones or design standards that could affect your site.

• What is the maximum height for an ADU in Claremont?

  In Claremont, 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 Claremont or county planning for your zone.

• Is ADU approval ministerial in Claremont?

  In Claremont, 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; Claremont planning can confirm the exact process.

• Are there parking requirements for ADUs in Claremont?

  In Claremont, parking for ADUs is generally true. California law often waives parking for ADUs within a half-mile of transit or in certain historic districts. Check with Claremont planning for your address.