ADU Regulations in Irvine, California (2026)

Regulations at a glance

Local rules & notes

Illegal Review Timeline: The City ordinance allows 120 days for permit approval, which violates the State maximum of 60 days. Subjective Design Standards: The City imposes subjective standards like 'harmony with the neighborhood', which are prohibited by State law requiring objective standards. Unlawful Parking Replacement: The City requires replacement parking when a garage is converted to an ADU, which is explicitly prohibited by State law. Fire Sprinkler Requirement: The City fails to exempt the primary dwelling from fire sprinkler retrofits when an ADU is added, violating State law.

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

Frequently asked questions about ADU regulations in Irvine

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

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

• What are the setback requirements for ADUs in Irvine?

  In Irvine, typical setback requirements are 5 feet from the side property line and 5 feet from the rear. These may be reduced to 4 feet under California Government Code § 65852.2 where applicable. Check with Irvine planning for overlay zones or design standards that could affect your site.

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

  In Irvine, the maximum height for an ADU is generally 15.5 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 Irvine or county planning for your zone.

• Is ADU approval ministerial in Irvine?

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

• Are there parking requirements for ADUs in Irvine?

  In Irvine, 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 Irvine planning for your address.