Can I build an ADU in Santa Barbara, California?
Yes. Santa Barbara allows an ADU in any zone that allows homes, approved ministerially with a building permit. A detached ADU can be up to 850 sq ft (1,000 sq ft with two or more bedrooms; 1,200 sq ft on lots of 15,000 sq ft or more) with 4-foot side and rear setbacks, and no parking is required outside High Fire Hazard Areas.
| Where allowed | Any zone allowing residential use [1] |
| Detached ADU max size (lots under 15,000 sq ft) | 850 sq ft (studio/1-bed); 1,000 sq ft (2+ bed) [3] |
| Detached ADU max size (lots 15,000 sq ft+) | 1,200 sq ft [3] |
| Attached ADU max size | 50% of the main home's living area (800 sq ft always allowed) [4] |
| JADU max size | 500 sq ft [5] |
| Interior (side/rear) setback for new ADU | 4 ft [6] |
| Parking | None required (except 1 space for non-studio ADUs in High Fire Hazard Areas, with exceptions) [7] |
| Detached ADU height | 18 ft (plus 2 ft to match roof pitch), or the main home's height/stories if greater [8] |
| Minimum rental term | 31 consecutive days [9] |
| Owner occupancy | Not required for ADUs (state law bars it); the ordinance's JADU requirement is enforceable under state law only when the JADU shares a bathroom with the house [11] |
Where and what kind
Ordinance 6103 (2023), which rewrote zoning §30.185.040, allows an ADU in any zone that allows residential use [1]. A junior ADU (JADU) of up to 500 sq ft must be inside the house or an attached garage [5]. In the Foothill and Extreme Foothill High Fire Hazard Areas, a standard ADU isn't allowed [2], but a smaller "special" ADU (detached up to 800 sq ft and 18 ft, or 16 ft in some areas) is. State law lets cities limit ADU locations for public-safety reasons but still requires the smaller by-right units, which the special-ADU rules provide.
Size, height and setbacks
- Detached: 850 sq ft (studio or 1-bed) or 1,000 sq ft (2+ bed) on lots under 15,000 sq ft; 1,200 sq ft on larger lots [3].
- Attached: up to 50% of the existing home's living area [4], but an 800-sq-ft ADU with 4-ft interior setbacks is always allowed regardless of floor-area or lot-coverage limits.
- Setbacks: zone front setback, 4 ft interior [6]; no setback for converting existing legal space.
- Height: up to 18 ft detached (plus 2 ft to match the main roof) or 25 ft attached, or the main home's height or stories if greater [8].
Parking
No parking is required, and a garage converted or torn down for an ADU needn't be replaced [7]. In High Fire Hazard Areas, non-studio ADUs need one space unless within half a mile of transit or another exception applies.
Rental and owner occupancy
No unit on the lot may be rented for less than 31 consecutive days [9], and the ADU can't be sold separately. The ordinance requires owner occupancy for all JADUs and, for RS-zone ADUs submitted on or after Jan. 1, 2025, "unless otherwise prohibited by State law" [10]. State law now permanently bars owner-occupancy requirements for ADUs, so that provision may be overridden; the city's ADU page says new ADU covenants don't require it [11]. State law also allows owner occupancy for a JADU only when it shares a bathroom with the house, so the JADU rule may be overridden for JADUs with their own bathroom.
Process
ADUs need a building permit and are approved ministerially within state deadlines [12]. You must post a notice sign within five days of applying and record an ADU agreement.
Ordinance 6103 predates the 2024-2025 state ADU bills, and the city says that where they differ, staff follows state law [11]. Starting January 1, 2027, state law (AB 956) will require cities to approve two new detached ADUs on a single-family lot. Coastal-zone properties follow Ord. 6104 (Title 28), which we have not reviewed.
See how Santa Barbara compares with 8+ other California towns on accessory dwelling units (adus) →
Next steps
- Check your zone, fire hazard area and whether you're in the Coastal Zone on the City's MAPS viewer or at the Planning Counter (805-564-5578, ADU@SantaBarbaraCA.gov).
- Review the City's ADU Guide and complete the ADU Supplemental Application.
- Submit a building permit application through the Accela Citizen Access portal and post the required notice sign on the property within five days.
- Sign and record the City's ADU agreement (covenant) before the building permit is issued.
Common questions
- Can I build an ADU in Santa Barbara, California?
- Yes. Santa Barbara allows an ADU in any zone that allows homes, approved ministerially with a building permit. In the Foothill and Extreme Foothill High Fire Hazard Areas a standard ADU isn't allowed, but a smaller "special" ADU is.
- How big can an ADU be in Santa Barbara, California?
- A detached ADU can be 850 sq ft for a studio or one-bedroom, or 1,000 sq ft with two or more bedrooms, on lots under 15,000 sq ft, and 1,200 sq ft on larger lots. An attached ADU can be up to 50% of the main home's living area, with 800 sq ft always allowed. A JADU can be up to 500 sq ft.
- What are the ADU setback and height rules in Santa Barbara, California?
- New ADUs need 4-foot interior (side and rear) setbacks plus the zone's front setback, with no setback for converting existing legal space. Detached ADUs can be 18 feet (plus 2 feet to match the roof) and attached ADUs 25 feet, or the main home's height if greater.
- Does an ADU need parking in Santa Barbara, California?
- No parking is required, and a garage converted or torn down for an ADU needn't be replaced. In High Fire Hazard Areas, non-studio ADUs need one space unless within half a mile of transit or another exception applies.
- Can I rent out my ADU as a short-term rental in Santa Barbara, California?
- No. No unit on the lot may be rented for less than 31 consecutive days, and the ADU can't be sold separately. Owner occupancy isn't required for ADUs under state law; the JADU requirement applies under state law only when the JADU shares a bathroom with the house.
California's statewide ADU law
California's ADU law (Gov. Code §§66310–66342, recodified from §65852.2; latest amendments effective January 1, 2026) overrides conflicting city rules, including in charter cities. Cities must approve ADUs ministerially (no hearing) within 60 days of a complete application, or the permit is deemed approved.
What cities cannot require or do:
- Owner-occupancy for an ADU.
- A minimum lot size.
- Side or rear setbacks over 4 feet for a new ADU, or any setback for a converted existing structure.
- Size, lot coverage or floor-area rules that block an ADU of at least 800 sq ft. Size caps can't be under 850 sq ft (1,000 for 2+ bedrooms).
- Parking within half a mile walking distance of public transit, or replacement parking for a garage converted to an ADU.
- Impact fees on ADUs of 750 sq ft or less.
By right on a single-family lot: one converted ADU plus one junior ADU (JADU, up to 500 sq ft inside the house), plus one new detached ADU (up to 800 sq ft, 16 ft tall). Owner-occupancy may be required only for a JADU that shares a bathroom.
Short-term rentals: cities may bar ADU rentals under 30 days, and must for by-right ADUs, JADUs and SB 9 units.
Coming January 1, 2027: AB 956 raises the by-right count to two new detached ADUs per single-family lot.
SB 9 (§§65852.21, 66411.7) allows two homes on a single-family lot, or a split into two lots of at least 1,200 sq ft (with a 3-year owner-occupancy affidavit).
What the ordinance says
- SBMC §30.185.040.C.1 (Ord. 6103) Where Permitted, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 3
An accessory dwelling unit may be permitted in any zone that allows residential use, located on a lot developed or proposed to be developed with one or more residential units, except as prohibited below.
- SBMC §30.185.040.C.3 Prohibited Locations, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 3
No standard accessory dwelling unit shall be permitted on a lot located within the Foothill or Extreme Foothill High Fire Hazard Areas (Very High Fire Hazard Severity Zone) as defined in the City's Community Wildfire Protection Plan adopted by City Council.
- SBMC §30.185.040.G.2.c Detached Accessory Dwelling Unit, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 8
(1) Lots up to 14,999 square feet and developed with one- bedroom or studio units: 850 square feet. (2) Lots up to 14,999 square feet and developed with two or more-bedroom units: 1,000 square feet. (3) Lots 15,000 square feet or larger: 1,200 square feet.
- SBMC §30.185.040.G.2.a Attached Accessory Dwelling Unit, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 8
An accessory dwelling unit that is attached to, and increasing the size of, the primary residential unit shall not exceed 50% of the living area of the existing primary residential unit.
- SBMC §30.185.040.G.2.d Junior Accessory Dwelling Unit, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 8
The maximum floor area of a junior accessory dwelling unit shall be 500 square feet.
- SBMC §30.185.040.G.5.a New Construction setbacks, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 9
Newly constructed accessory dwelling units shall comply with the following setback standards: (1) Front Setback: Meet the minimum front setback for residential structures in the zone, unless further limited by Subsection H.8, Front Yard Location, below. (2) Interior Setback: Four feet.
- SBMC §30.185.040.J Parking Standards, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 14
No automobile parking spaces are required for accessory dwelling units or junior accessory dwelling units.
- SBMC §30.185.040.H.7.c Height, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 11
18 feet for a detached standard or special accessory dwelling unit; an additional two feet in height is allowed if necessary to match the roof pitch and height of the primary residential unit; or
- SBMC §30.185.040.E.2 Rental Terms, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 4
If rented, rental terms for the primary residential unit, accessory dwelling unit, or junior accessory dwelling unit shall not be less than 31 consecutive days, nor shall rental terms allow termination of the tenancy prior to the expiration of at least one 31-day period occupancy by the same tenant.
- SBMC §30.185.040.E.3.b Owner Occupancy, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 5
Any accessory dwelling unit located in an RS zone submitted on or after January 1 , 2025, unless otherwise prohibited by State law, or upon repeal of Government Code Section 65852.2 (a)(8)(B) removing the state-imposed prohibition of an owner occupancy requirement, whichever occurs first.
- ADU Project Guidance page, Is owner occupancy required?, Accessory Dwelling Unit Project Guidance page, p. 1
Owner-occupancy is not required on any new ADU covenants. However, if you are proposing a Junior ADU, the property owner must still reside in either the primary residential unit or the JADU.
- SBMC §30.185.040.M Building Permit Required, Ordinance No. 6103 amending SBMC 30.185.040 Accessory Dwelling Units (adopted Feb 14, 2023), p. 18
All accessory dwelling units and junior accessory dwelling units shall comply with applicable state and local building codes and shall require approval of a building permit.