Accessory Dwelling Units

Attic ADU Conversion
ADU Addition Above Existing Garage
New Detached ADU
Garage Conversion ADU
Efficiency Kitchen

Types of ADUs

There are two types of ADUs: standard ADUs and Junior ADUs [also known as JADUs]. There is also a third option, the “Efficiency Kitchen Alternative”.

Standard ADUs involve creation of a new independent living unit with separate exterior entrance from a primary single- or multifamily dwelling. There are three ways that standard ADUs can be created on a property:

  1. Conversion: Convert part of the existing home, garage or accessory structure; or
  2. New Construction – Attached: Build a new addition to the existing home or attached garage; or
  3. New Construction – Detached: Build a new, free-standing dwelling unit on the property or build an addition to an existing detached garage or accessory structure.

JADUs involve creation of a new living unit, maximum 500 square feet, converted from within the walls of a single-family dwelling, including attached garages and other nonliving spaces. JADUs have an efficiency kitchen and a separate exterior entrance. A JADU may have interior access to the primary dwelling but this is not required. Bathrooms can be separate or shared with the primary dwelling.

The summary table below can help you decide which ADU is right for you. As noted in the table footnote, one standard ADU of 800 square feet is always allowed on residential parcels, regardless of other size maximums or site standards. See County Code Section 13.10.681 for full details.

ADU Type Min Size Max Size* Max Height ⱡ Setbacks ⱡ Parking**
Junior ADU 150 sf 500 sf N/A*** Minimum required for fire safety*** N/A
Standard ADU: Conversion 150 sf No maximum N/A*** Minimum required for fire safety*** N/A
Standard ADU: Attached New Construction 150 sf Parcel < 1 acre:
1 bedroom: 850 sf,
2+ bedrooms: 1,000 sf, or 50% of primary dwelling, whichever is less

Parcel ≥ 1 acre:
50% of primary dwelling
28 ft

ADUs above detached garages: 24 ft (20 ft at exterior wall)
Front setback: zone district standard.

Side setback: 4 feet.

Rear setback: 4 feet up to 16-foot building height, 8 feet for greater than 16 foot building height.
1 space/ ADU
Standard ADU: Detached New Construction 150 sf Parcel < 1 acre:
1 bedroom: 850 sf
2+ bedrooms: 1,000 sf

Parcel ≥ 1 acre: 1,200 sf
Inside USL: 16 ft****
Outside USL: 28 ft

ADUs above detached garages: 24 ft (20 ft at exterior wall)
1 space/ ADU

*Regardless of other ADU size requirements or FAR or lot coverage, one ADU of 800 sf is allowed.

**Some new construction ADUs may be except from parking requirements due to location. Replacement parking is not required for ADUs that are converted from existing garages, except within certain areas in the coastal zone.

***Conversion ADUs and JADUs can include up to 150 square feet of new construction. Any new construction portions of conversion ADUs and JADUs must meet applicable ADU height and setback standards.

****Detached ADUs within the USL may be up to 21 feet with design review and Zoning Administrator approval.

ⱡ Special height and setback rules apply in the Pleasure Point and Seascape Beach Estates neighborhoods.

The County allows one full kitchen and one efficiency kitchen in any dwelling unit. The efficiency kitchen can be within a JADU but this is not required. Some applicants may find that a non-ADU “efficiency kitchen” alternative is preferable to constructing an official ADU or JADU. The following table compares key project considerations for these three options.

Project Considerations Standard ADU Junior ADU Efficiency Kitchen Alternative
Primary residence Type Single- or multifamily Single-family Single- or multifamily
Construction type New construction or conversion, attached or detached Conversion from space primarily within the walls of a single-family home New construction or conversion, attached*
Min/Max size Min: 150 sf
Max: 850, 1,000, 1,200 sf or 50% of the primary dwelling depending on ADU type and property size. 800 sf ADU allowed regardless of FAR/lot coverage.
Min: 150 sf
Max: 500 sf
No minimum size.
Maximum size constrained by maximum FAR and lot coverage.
Interior access to primary dwelling Not required Not required Required
Separate bathroom Full bathroom required Full bathroom required (may be shared with primary dwelling) Full or half bathroom allowed (not required).
Kitchen facilities Full kitchen allowed Efficiency kitchen required Efficiency kitchen allowed
Owner occupancy Required (deed restriction) EXCEPT for ADUs permitted between 1/1/20 and 1/1/25. Required (deed restriction) Not required
Approval required Building permit** Building permit** Building permit**
Approval timeline 60 days from date of complete building permit application submittal 60 days from date of complete building permit application submittal No required timeline for building permit review
Fees*** Administrative fees, building permit review fees (waived for ADUs < 640 sf), impact fees (waived for ADUs <750 sf), utility connection fees (waived for Conversion ADUs) Administrative fees, building permit review fees (may be waived for JADUs) Administrative fees, building permit fees, certain impact fees

* Habitable non-ADU detached accessory structures are allowed but these structures cannot include kitchens and usually cannot include bathrooms. For more information about non-ADU habitable accessory structures, please see the Santa Cruz County Code, section 13.10.611.

** In some zone districts and for some types of sites, discretionary site development approval from the Planning Department, Zoning Administrator, or other agency may be required prior to obtaining a building permit.

*** Fees listed here cover building permits only. When discretionary approval is required, additional fees apply.