ADU Regulations in Huntington Beach, California (2026)

Regulations at a glance

Local rules & notes

Development Impact Fee Reduction: For ADUs larger than 750 sq ft, the city applies a flat 75% reduction in Development Impact Fees (DIF), which is a specific defined discount rather than a vague 'proportional' calculation. Coastal Zone Restrictions: Properties in the Coastal Zone are subject to additional requirements, including potential Coastal Development Permits and the enforcement of replacement parking for garage conversions. Fire Separation Upgrades: The document explicitly details that existing single-family homes may need upgrades to exterior walls, projections, and openings to meet 2022 CRC Section R302 if fire separation distances are insufficient.

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

Frequently asked questions about ADU regulations in Huntington Beach

• What is the maximum ADU size in Huntington Beach, California?

  In Huntington Beach, 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; Huntington Beach may follow state defaults or have local limits. Verify with Huntington Beach planning for your specific lot.

• What are the setback requirements for ADUs in Huntington Beach?

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

• What is the maximum height for an ADU in Huntington Beach?

  In Huntington Beach, 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 Huntington Beach or county planning for your zone.

• Is ADU approval ministerial in Huntington Beach?

  In Huntington Beach, 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; Huntington Beach planning can confirm the exact process.

• Are there parking requirements for ADUs in Huntington Beach?

  In Huntington Beach, 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 Huntington Beach planning for your address.