California ADU rules · Santa Barbara County
Can I Build an ADU in Santa Barbara?
Yes — you can build an ADU in Santa Barbara. California's statewide ADU law requires every city, including Santa Barbara, to approve a qualifying accessory dwelling unit by right, plus a junior ADU (JADU) on a single-family lot. What varies city to city are the local specifics below.
Can you build one?
ADUs allowed
CA state lawYes — by right
ADUs and JADUs are allowed by right in all residential and mixed-use zones; ministerial approval, no hearing.
Units on a single-family lot
CA state law1 ADU + 1 JADU
At least one ADU and one JADU per single-family lot (a conversion ADU may also be possible).
Units on a multifamily lot
Local ruleup to 2 detached ADUs, or up to 25% of existing units as conversions (minimum 2), whichever is greater
Santa Barbara limits detached ADUs on multifamily lots to 2, but allows at least 2 conversion ADUs or 25% of units.
Junior ADU (JADU)
CA state lawAllowed
Up to 500 sq ft, within the walls of an existing single-family home (single-family lots only).
Size & height
Max detached ADU size
Local rule1,200 sq ft
Detached ADU max: 850/1000 sq ft on lots <15,000 sq ft, 1200 sq ft on lots ≥15,000 sq ft; 800 sq ft for 'special' ADUs.
Max attached ADU size
Local rule50% of primary, >=800
Attached ADU may not exceed 50% of primary dwelling, but not less than 800 sq ft.
Guaranteed minimum size
CA state law800 sq ft
An 800 sq ft ADU must be allowed regardless of FAR/lot-coverage caps; a city also cannot cap an attached ADU below 850 sq ft (1,000 for 2+ bedrooms).
Max JADU size
CA state law500 sq ft
Max height
Local rule18 ft
Detached ADU: 18 ft/1 story; up to 20 ft to match primary roof; 16 ft in VHFHSZ and not near transit. Attached: up to 25 ft or primary height.
Setbacks
Side setback
CA state law4 ft
A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.
Rear setback
CA state law4 ft
Front setback
Local rulemust meet minimum front setback for the zone
Front setback must meet base zone; conversions exempt.
Separation from main house
Local rule5 ft
Detached ADUs must be at least 5 feet from the primary dwelling.
Parking
Parking required
CA state lawUp to 1 space
At most 1 space per ADU (or per bedroom, whichever is less) — and waived in the common cases below.
Transit parking exemption
CA state lawYes — no parking required near transit & for conversions
No parking may be required within ½ mi walking distance of transit, in a historic district, for an ADU within an existing structure, within one block of car-share, or in certain permit-parking areas.
Garage-conversion replacement parking
CA state lawNot required
When a garage/carport is demolished or converted to build an ADU, replacement parking cannot be required.
Approval, timeline & cost
Approval path
CA state lawMinisterial (by right)
No public hearing or discretionary design review for a qualifying ADU.
Approval timeline
CA state law60 days
The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.
Owner-occupancy
CA state lawOnly for a JADU
No owner-occupancy requirement for ADUs (the prior sunset was removed). A JADU may require owner-occupancy, principally where it shares sanitation with the main house.
Impact-fee waiver
CA state lawWaived under 750 sq ft
An ADU of 750 sq ft or less pays no impact fees (the 750 sq ft threshold itself is exempt under § 66311.5); larger ADUs pay fees proportional to the primary dwelling. JADUs (≤ 500 sq ft) are exempt.
Permits required
Local ruleBuilding permit, Coastal Development Permit (in coastal zone)
Coastal Development Permit required in coastal zone.
Santa Barbara-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Foothill/Extreme Foothill High Fire Hazard Areas (VHFHSZ)
ADUs generally prohibited except for 'special' ADUs per §28.86.090.
Coastal Zone
ADUs require Coastal Development Permit and must be consistent with Coastal Land Use Plan.
Historic Districts/Historic Resources
ADUs allowed but subject to additional design review if on/near historic resources.
Hillside Areas
Additional design standards may apply.
Santa Barbara sets a 5-foot minimum separation between detached ADUs and the primary dwelling, limits detached ADUs on multifamily lots to 2, and applies stricter fire, coastal, and historic resource rules. Detached ADU size varies by lot size, with a local maximum of 1,200 sq ft on large lots.
Frequently asked questions
Can I build an ADU in Santa Barbara?
Yes. California's statewide ADU law requires Santa Barbara to approve a qualifying accessory dwelling unit ministerial (by right), plus a junior ADU (JADU) on a single-family lot.
How big can an ADU be in Santa Barbara?
A detached ADU of at least 1,200 sq ft must be allowed, and an ADU of 800 sq ft can never be zoned out by floor-area or lot-coverage limits. A JADU can be up to 500 sq ft.
What are the setback requirements for an ADU in Santa Barbara?
Side and rear setbacks are limited to 4 ft. must meet minimum front setback for the zone.
Is parking required for an ADU in Santa Barbara?
Up to 1 space. No parking can be required within ½ mile of transit, for conversions, or for units inside the primary home. When a garage is converted, replacement parking is not required.
How long does ADU approval take in Santa Barbara?
A complete application must be acted on within 60 days, with ministerial (by right) — no public hearing or discretionary design review for a qualifying ADU.
Do I have to live on the property to build an ADU in Santa Barbara?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Santa Barbara Municipal Code Chapter 28.86 (Ord. 6104 §1, 2023)
- §28.86.035, §28.86.090
- §28.86.055.B.3, §28.86.090.D.1
- §28.86.055.B.1
- §28.86.090.E, §28.86.055.B.3
- §28.86.055.F, §28.86.090.F
- §28.86.055.D
- §28.86.100
- §28.86.030
- §28.86.060, §28.86.070
- §28.86.060
- Cal. Gov. Code §§ 66310–66342 (ADU Law)
- HCD 2025 Accessory Dwelling Unit Handbook
- Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)
- Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66333 (junior ADUs)
- Cal. Gov. Code § 66321 (size minimums & height)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
- Cal. Gov. Code § 66314 (local ordinance standards)
- Cal. Gov. Code § 66315 (owner-occupancy)
- Cal. Gov. Code § 66311.5 (impact fees: none for an ADU ≤ 750 sq ft or JADU ≤ 500 sq ft)
Last updated 2026-06-25. This is an AI-assisted summary of Santa Barbara's ADU rules, drawn from its published ordinance and California ADU law — general information, not legal advice, and it may be incomplete or out of date. Verify the controlling rule for your specific parcel with Santa Barbara Planning before relying on it.
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