Residential or Mixed Use zoned lot with a single-family dwelling unit: Up to 1 Junior ADU plus 1 Detached ADU, OR 1 single Attached ADU.
Multi-family lot: Minimum 1 within existing multifamily residence, up to 25% of existing units, when existing space is converted to ADU. Up to 2 ADUs may be detached.

Single family and multi-family residential lots will not be subject to the minimum lot size of the underlying zoning district or by ordinance for Accessory Dwelling Unit (ADU) projects. ~ Updated: State Law AB-68

Detached or Attached Single Family: Detached ADU – 1,200 sf
-On a lot with a JADU, a detached ADU is limited to 850 sf (or 1,000 sf if detached ADU provides more than one bedroom)
Attached ADU – whichever is less restrictive of:
-50% of living area, or
-850 sf (or 1,000 sf if attached ADU provides more than one bedroom)

Created from existing space Detached ADU – 1,200 sf
-On a lot with a JADU, a detached ADU is limited to 850 sf (or 1,000 sf if detached ADU provides more than one bedroom)
Attached ADU – whichever is less restrictive of:
-50% of living area, or
-850 sf (or 1,000 sf if attached ADU provides more than one bedroom)
Junior ADU – 500 sf

Front – By zone
Side – 4 feet2
Street side-yard – By zone
Rear – 4 feet2

None required if:
(1) ADU is within ½ mile walking distance of public transit (i.e. bus, rail, and Lyft SC Ride stops).
(2) ADU is within an architecturally and historically significant historic district.
(3) On-street parking permits are required but not offered to the occupant of the accessory dwelling unit.
(4) There is a car share vehicle located within 1 block of ADU.
None required if ADU is part of the proposed or existing primary residence or an accessory structure.

Required if required for the primary residence. Consistent with the Building Code, fire sprinklers may be required if new or reconstructed setbacks are less than 5 feet.

(iii) To passageway shall be required during construction of an accessory dwelling unit. The design, building, and roofing materials, colors, and overall appearance of the accessory dwellingunit shall be generally consistent with the principal unit. Accessory dwelling units may be rented, but shall not be used as a boarding or rooming house, as definedin Title 9, Appendix A.

16 feet for Detached ADUs (unless created from existing space), otherwise permitted by zone

State Standards don't require any additional design review.

Not specified by State Standards.

Any ADU/JADU(s) may not be sold or otherwise conveyed separately from the primary residence. This is conveyed in the deed restriction required upon submittal of an ADU application.
 Owner Occupancy: Not required for ADUs created between January 1, 2020, and December 31, 2024, unless a Junior ADU is on the property. Then the owner must live in the primary residence or the Junior ADU.

Local health officer approval where a private sewage disposal system is being used, if required. (State requirements)

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