ADU Regulations in Dublin, California (2026)

Regulations at a glance

Local rules & notes

Affordable Housing Fee Exemption: ADUs are explicitly listed with a $0.00 rate for the Affordable Housing Fee, which is otherwise significant ($42.58/sq ft for single-family). Sewer Connection Fee Calculation: Sewer fees for ADUs are charged on a per-square-foot basis ($2.22 City + $9.75 Regional) rather than the flat unit rate applied to primary dwellings. Flood Protection Fee Waiver: The Flood Protection and Storm Water Drainage Fee ($1.00/sq ft of impervious surface) is waived for ADUs smaller than 750 sq ft. Tri-Valley Transportation Fee Exemption: ADUs are exempt from this regional transportation impact fee.

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

Frequently asked questions about ADU regulations in Dublin

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

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

• What are the setback requirements for ADUs in Dublin?

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

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

  In Dublin, 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 Dublin or county planning for your zone.

• Is ADU approval ministerial in Dublin?

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

• Are there parking requirements for ADUs in Dublin?

  In Dublin, 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 Dublin planning for your address.