Under state law, each single-family home may now build at least one ADU. Owner occupied single-family parcels may build one ADU and one Junior ADU. Multi-family parcels, per every four existing residential units, may build one ADU, so long as the existing units were legally established.

Residential properties will not be subject to any minimum lot size for ADUs by ordinance or of the underlying zoning district. ~ AB-68

Notwithstanding the dwelling unit minimum described in Section 30. 140. 150, Residential Unit, the minimum floor area for a newly constructed accessory dwelling unit is as follows:
a. Efficiency Unit: 150 square feet.
b. Studio Unit: 220 square feet.
c. All Other Units: 400 square feet.

Attached ADU: The primary residential unit shall not exceed 50% of the living area of the existing primary residential unit
Converted ADU: An adu that is incorporated entirely within an existing primary resdiential unit, or within an existing accessory building, is not limited in size except that it shall not exceed the footprint of the existing structure
Detached ADU: An ADU that is detached from the primary residential unit and may or may not be attached to another detached accessory building, including detached garages, shall not exceed the max floor area based on lot size and number of bedrooms
- Lots up to 14,999 sq. ft. and developed with one-bedroom or studio units: 850 sq.ft.
- Lots up to 14,999 sq. ft. and developed with two or more bedroom units: 1,000 sq. ft.
- Lots 15,000 square feet or larger: 1,200 square feet
JADU: The max floor area of a JADU shall be 500 square feet

New Construction:
- Front Setback: Met the minimum front setback for residential structures in the zone, unless further limited by subsection H.8., Front Yard Location, below
- Interior Setback: Four Feet
Conversion: No setback is required to convert the existing, legally permitted, floor area of a main or accessory building to an accessory dwelling unit. Improvements to existing nonconforming buildings, including conforming additions, are allowed pursuant to chapter 30.165, Nonconforming structures, Site Development, and uses.
Substantial Redevelopment: No setback is required when an existing main or accessory building is substantially redeveloped and converted to an accessory dwelling unit, provided that the new building is reconstructed int eh same location and with the same dimensions and floor area as the existing building.
- Exceptions: One small 150 square foot conforming first floor addition may be permitted on a substantially redeveloped and converted nonconforming accessory building New Construction Combined With Replacement of Nonconforming garage: The construction of an accessory dwelling unit may be combined with the demoltiion and replacement of a nonconforming detached garage if all the following are met:
- The new garage is enlarged only as necessary to provide the same number of parking spaces and to meet the dimension requirements of the City of Santa Barbara Access & Parking Design Standards, but located no closer to the property line as the existing garage; and
- The accessory dwelling unit is constructed above the reconstructed garage; and
- The accessory dwelling unit and any additions to the garage shall conform with current setbacks; and v. The new structure shall comply with all applicable height and building story limitations, and all other development standards are met. e. Setback Encroachments. Setback encroachments allowed pursuant to Section 30.140.090, Encroachments into Setbacks and Open Yards, may be permitted for accessory dwelling units or junior accessory dwelling units.

5 feet of separation required for the primary building

No automobile parking spaces are required for accessory dwelling snits or junior accessory dwelling units. The required parking for the existing residential mits on site may be reduced or replaced as follows to construct an accessory dwelling unit:
I. No Replacement Parking Required When an existing garage, carport, or other covered parking structure is converted to an accessory dwelling unit or demolished in order to construct an accessory dwelling unit, those off-street parking spaces for the existing residential unit are not required to be replaced.
II. Optional Parking Standards. If optional new or replacement parking spaces are proposed for either the primary residential unit or the accessory dwelling unit, those spaces may be provided as covered, uncovered, in a mechanical lift, or in a tandem configuration pursuant to f. below. The replacement spaces shall meet all of the following:
a. Covered parking shall meet the development standards applicable to the primary residential unit within the zone in which the lot is located.
b. All parking spaces must meet the minimum dimensions and development standards consistent with the City Parking Access & Design Standards and Section 30.175.090 Parking Area Design and Development Standards.
c. In order to maintain visibility for adjacent driveways and intersections, uncovered parking spaces shall comply with Section 30.140.230, Visibility at Driveways and Intersections.
d. Replacement uncovered parking spaces may be allowed in a front or interior setback, provided all uncovered parking spaces are contained within the area of an existing paved driveway and no increase to paved areas occurs in the setbacks.
e. New uncovered parking spaces, that are not replacement parking spaces as described above, may be located three feet from any interior lot line, provided a minimum of three feet in width of planting area is provided for the length of the paved parking area along the interior lot line.
f. Tandem parking configuration shall meet all the following:
-- i. No more than two automobiles shall be placed one behind the other.
-- ii. Both automobile parking spaces parked in tandem shall be assigned to the same residential unit. Tandem parking shall not create any traffic safety issues.
-- iii. Vertical or stackable tandem parking, provided by means of mechanical lifts, is subject to approval by the Public Works Director. Mechanical lifts shall be fully enclosed within a structure and shall require a recorded maintenance agreement, pursuant to Chapter 30.260, Recorded Agreements.
-- iv. Tandem parking in multi-unit and commercial zones is subject to approval by the Public Works Director. Tandem parking shall not create traffic safety issues.

Accessory dwelling units shall not be required to provide fire sprinklers if they are not required for the primary dwelling.

-- No standard accessory dwelling unit shall be permitted on a lot located within the Fire Hazard Area (Extreme Foothill and Foothill), or as may be subsequently retitled in the future as the "Very High Fire Hazard Severity Zone," as defined in the City's Community Wildfire Protection Plan adopted by City Council.

a. Exception for Special Accessory Dwelling Units. Accessory dwelling units permitted in accordance with all the configuration, standards, and special procedures outlined in subsection L. Development Standards for Special Accessory Dwelling Units, may be permitted on any lot, including lots located within any Fire Hazard Area (Extreme Foothill and Foothill), or as may be subsequently retitled in the future as the "Very High Fire Hazard Severity Zone," as defined in the City's Community Wildfire Protection Plan adopted by City Council, if the lot is zoned to allow for residential use and contains an existing or proposed primary residential unit.

I. Prohibition of Shiny Roofing and Siding. New roofing and siding materials that are, shiny, mirror-like, or of a glossy metallic fetish are prohibited.
2. Roof 771e. Where a new clay tile roof is proposed, the use of two-piece terra cotta (Mission "C-tile") roof is required and "S-tile" is prohibited, unless necessary to match the S-tile roof materials of the existing primary residential unit.
3. Skylights. New skylights shall have flat glass panels. "Bubble" or dome type skylights are not allowed.
4. Glass Guardrails. New glass guardrails are not allowed, unless necessary to match the glass guardrails of the existing primary residential unit.
5. Garage Conversion. If a garage is converted to an accessory dwelling unit, the garage door opening shall be replaced with exterior wall coverings, or residential windows and doors, to match the existing exterior garage wall covering and detailing.
6. Grading. No more than 250 cubic yards of grading (i.e., cut and/or fill under the main accessory dwelling unit building footprint and outside the main building footprint to accommodate the accessory dwelling unit) is proposed in the Hillside Design District or on lots in other parts of the City with a slope of 15% or greater.

Height:
The construction of an ADU shall nto exceed the following, whichever is greater
a. height of the primary residential unit,
b. Number of stories of the primary residential unit, or
c. 17 feet
The height limitation is not applicable to an ADU constructed above a grage, however, in no event shall the resulting building exceed the maximum height or number of stories allowed for a detached or attached accessory building in the zone.

Architectural Review. All accessory dwelling units or junior accessory dwelling units shall be subject to the following architectural design criteria as applicable to either new construction or exterior alterations, which shall be reviewed ministerially by the Community Development Director. For purposes of this section, portions of a building or site considered to be the accessory dwelling unit shall include all of the contiguous interior livable floor area of the accessory dwelling unit and any exterior alterations directly attached to, and integral to, the livable floor area of the accessory dwelling unit.

When a local agency that has not adopted an ordinance governing accessory dwelling units in accordance with subdivision (a) receives an application for a permit to create an accessory dwelling unit pursuant to this subdivision, the local agency shall approve or disapprove the application ministerially without discretionary review pursuant to subdivision (a) within 120 days after receiving the application. design review. design review is NOT required for an accessory dwelling unit. design review is required for unrelated work to the site or primary dwelling, if that work requires design review for some other reason (e.g., Hillside Design District, etc.) If any work to the primary
residence requires design review, submit the completed design review application to the
Planning Counter. Remove all references to the accessory dwelling unit from the design review submittal (to the maximum extent feasible).
5. OTHER APPLICATIONS REQUIRED. Existing zoning standards may require additional
applications. If a project requests relief from applicable zoning standards please consult the Planning Counter to discuss viable options.

Not specified by State Standards. Copy Link

Between between 2020 and 2025, owner occupancy requirements will not apply to new Accessory Dwelling Unit (ADU)s. (applicable to new construction and conversion units) ~ SB13

Approval by the local health officer where a private sewage disposal system is being used, if required.

(1) Fees charged for the construction of accessory dwelling units shall be determined in accordance with Chapter 5 (commencing with Section 66000) and Chapter 7 (commencing with Section 66012).

(2) accessory dwelling units shall not be considered by a local agency, special district, or water corporation to be a new residential use for the purposes of calculating connection fees or capacity charges for utilities, including water and sewer service.

(A) For an accessory dwelling unit described in subdivision (e), a local agency, special district, or water corporation shall not require the applicant to install a new or separate utility connection directly between the accessory dwelling unit and the utility or impose a related connection fee or capacity charge.

Exceptions. Discretionary applications for design review may be requested in the following circumstances: a. An applicant may propose an accessory dwelling unit that does not meet these design criteria subject to approval by the Single Family Design Board, Architectural Board of Review, or Historic Landmarks Commission, as appropriate. b. Discretionary design review may be required for any exterior alterations to the project site or main buildings that are not an integral part of the accessory dwelling unit, but are proposed in conjunction with the accessory dwelling unit, if required pursuant to Chapter 22.22, 22.68, or 22.69 of this code.

*** Beginning in 2020, according to state law, all residential zoning districts, including single-family and multi-family, are allowed to build Accessory Dwelling Units. ***

The lot is zoned to allow single-family or multifamily use.

http://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=GOV&sectionNum=65852.2

Local building code requirements that apply to detached dwellings, as appropriate.