Summary
ADUs and Junior ADUs (JADUs) are independent living units that are associated with a primary dwelling unit and allow for housing flexibility for those seeking rental income, housing for family members or households that are downsizing. This bulletin describes the types of small living unit options and principles for constructing.
What is an ADU?
An ADU is an independent residential dwelling unit located on a lot with a primary dwelling unit. ADUs must include permanent provisions for living, sleeping, eating, cooking and sanitation.
ADUs: Basic Requirements
- ADUs are allowed on any parcel with a zone district or General Plan designation that allows residential or mixed uses. No minimum lot size is required.
- A primary dwelling must exist or be planned on the parcel (on a vacant lot, the owner may build an ADU and primary dwelling at the same time or sequentially), except in cases of rebuilding after a disaster.
- ADUs can be attached to the primary dwelling or detached; they can be new construction or converted from existing space.
- ADUs are subject to special development standards, depending on whether they are “New Construction” or “Conversion” ADUs (please see publication: ADU Development Standards).
- Different ADU standards and permitting may apply to parcels in the following locations:
- Coastal Zone
- Agricultural, timber and park land
- Pleasure Point (PP) Combining Zone District
- Seacliff Beach Estates (SBE) Combining Zone District
- Parcels with environmental hazards or protected resources
800-Square Foot Allowance
On properties where existing buildings meet or exceed maximum allowed floor area ratio (FAR) or lot coverage limits, property owners can still build a New Construction ADU up to 800 square feet with a height of 16 feet, meeting other ADU standards.
Junior ADUs
Property owners with single-family dwellings may also construct Junior ADUs (JADUs). JADUs are subject to the following criteria:
- Owner must live onsite.
- Maximum size is 500 square feet, which can include an addition up to 150 square feet.
- Must be converted from within the walls of the single-family dwelling (including both habitable and non-habitable spaces such as garages or storage areas). Not allowed in detached garages or on multifamily sites.
- Must have a separate exterior entrance and access to a full bathroom (independent or shared with the primary dwelling).
Efficiency Kitchen Alternative
The County allows one full kitchen and one efficiency kitchen in single-family or multifamily dwelling units. A JADU may have standard kitchen or an efficiency kitchen. Some applicants may find that a non-ADU “efficiency kitchen” alternative is preferable to constructing an official ADU or JADU. For a comparison, please see publication: ADU Development Standards.
Number of ADUs Allowed
Parcels with single-family dwellings:
1 ADU + 1 JADU per dwelling
Parcels with multifamily dwellings:
2 detached ADUs per lot (may be attached to each other) + 25% of units may have ADUs converted from non-living space such as garages and storage areas.
Parcels where the number of existing dwellings exceeds what is allowed:
If the existing dwelling units were constructed legally, they would be considered “legal nonconforming.” The ADUs allowed would depend on the structures and zone district.
ADUs and Short-Term Rentals
Short-term rentals (rentals of less than 30 days) are prohibited in ADUs. Any property with an ADU is not eligible for the County’s Vacation Rental or Hosted Rental program.
ADUs and Owner Residency
Parcels with JADUs require owner occupancy. Parcels with ADUs permitted January 1, 2020 - January 1, 2025 do NOT require owner occupancy unless there is also a JADU on site. ADUs permitted before January 1, 2020 require owner occupancy.
ADUs and Solar Panels
Detached, new construction ADUs are typically not required to install PV systems, however, all new structures are required to conform to California Energy Code, Title 24 standards which could necessitate installation of a photovoltaic system.
Conversion ADUs
An existing legal garage, accessory structure or dwelling unit may be converted to an ADU. There is no maximum size, but if you add more than 150 sq.ft. of new floor area, the unit is considered “new construction” and subject to maximum size limitations. Legal, nonconforming structures may also be converted; structures built without benefit of permits may be converted but are considered new construction and have to meet current building code and zoning regulations.
Code Enforcement Amnesty
Between January 1, 2020 and January 1, 2030, ADUs constructed before January 28, 2020 with code violations (including ADUs in illegal structures) may request to defer code enforcement for up to five years, subject to a County determination that there is not an imminent risk to health and safety.
The Permit Process
An ADU requires a building permit using the County’s online ePlan review process: http://scceplanreview.santacruzcounty.us/.
To apply for a permit, you will need full construction plans and the application fee. For a complete list of required application materials, review the ePlan website or visit the Building Counter on the 4th Floor of the Government Center at 701 Ocean Street. In some situations, discretionary approval may be required in addition to a building permit.
Note that fire districts, water agencies, and sanitation agencies (Dept. of Public Works sanitation or Environmental Health Services) review building permits for compliance. Applicants in the Soquel Creek Water District must receive a “Will Serve” letter for New Construction ADUs.
Questions?
Use the Planning Dept. website to make an appointment for a visit or phone call from the Planning Counter during counter hours (M-Th, 8:30-11:30 am). Emails and phone calls outside counter hours are usually returned within 24 hours – see contact info below.