User Guide Appendix A: ADU & JADU Guidelines

Sacramento County Zoning Code
User Guide
Appendix A: ADU & JADU Guidelines

[ADDED 10-22-2026]

A.1 Purpose and Definitions

The purpose of Appendix A of the Sacramento County User Guide is to provide the most up to date guidelines for permitting state-mandated Accessory Dwelling Units (ADU) and Junior Accessory Dwelling Units (JADU) within the unincorporated area of Sacramento County.

Appendix A is not an Ordinance. The ADU Ordinance for Sacramento County was formally repealed on October 22, 2026 as requested by the California Department of Housing and Community Development.

Appendix A is intended to be administratively updated by the Planning Director, from time to time, to ensure efficient review and approval processes for ADUs and JADUs, in compliance with State law.

A.1.A Relationship to State Law

Pursuant to Section 6.8.2.F of the Zoning Code, in case of any conflict between this Appendix and State ADU law provisions, State law provisions shall prevail. Where silent, provisions here shall defer to State ADU law codified in CA GOV § 66310-66342, as may be amended from time to time.

A.1.B Definitions

For all definitions of terms used in ADU law, please refer to CA GOV § 66313.

A.1.B.1 Accessory Dwelling Unit

CA GOV § 66313(a)

An attached or a detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. It shall include permanent provisions for living, sleeping, eating, cooking, and sanitation on the same parcel as the single-family or multifamily dwelling is or will be situated. An accessory dwelling unit also includes the following:

1. An efficiency unit.
2. A manufactured home, as defined in Section 18007 of the Health and Safety Code.

A.1.B.2 Junior Accessory Dwelling Unit

CA GOV § 66313(d)

A unit that is no more than 500 square feet of interior livable space in size and contained entirely within a single-family residence. A junior accessory dwelling unit may include separate sanitation facilities, or may share sanitation facilities with the existing structure.

A.1.B.3 Efficiency Kitchen

CA CBC § 1208.4(3)

A cooking facility with appliances, a sink, a food preparation counter, and storage cabinets that are of a reasonable size in relation to the dwelling unit. In comparison to a “kitchen,” an efficiency kitchen may satisfy the requirement of cooking appliances with one or more 120-volt appliances, such as a microwave or hot-plate.

A.1.B.4 Multifamily

HCD ADU Handbook (as amended March 2026) § Definition of “Multifamily Dwelling”

“Multifamily” for purposes of compliance with State ADU regulations and all use of the term in this Appendix shall mean any parcel developed with at least one set of two attached dwelling units not classified as ADUs.

A.1.B.5 Front Yard

Section 7.3 of the Zoning Code, replicated for reference.

On an interior lot, a yard extending from the full width of the lot between the front of the main building and the front lot line. The depth of the required front yard shall be measured horizontally between the nearest part of the closest building and the nearest point of the front lot line. On a corner lot, the combined yards extending between the main building and adjacent street frontages. When a required “Side Street” setback is specified, such setback shall apply to the portion of the front yard as described in the definition of “Side Street Yard,” as provided in Section 7.3 of the Zoning Code. If no “Side Street” setback is specified, the “Front Yard” required setback shall apply to all frontages on a corner lot.

A.2 General Guidelines

A.2.A Authority

CA GOV § 66323(a)

1. The County has no discretionary process for review of ADU applications and only imposes ministerial review through building permits for ADUs as is required by State law.

2. Requests for deviation from standards provided in this Appendix and/or CA GOV § 66310-66342 are prohibited as pursuant to CA GOV § 66323, ADUs cannot be subject to discretionary processes.

A.2.B Permitted Zones

CA GOV § 66323(a)

ADUs and JADUs shall be permitted in residential or mixed-use zones. This includes the Single-Family Residential, Multiple Family Residential, Commercial, and Mixed-Use Zoning District Sequences provided in Section 2.1.4.A of the Zoning Code.

A.2.C Minimum Size of All ADUs

CA HSC § 17958.1(a)

In no circumstance shall any type of ADU be less than 150 square feet.

A.2.D Short-Term Rental Prohibition

CA GOV § 66323(e) & 66333(g)

An ADU shall not be used for short-term rental/lodging purposes (30 days or less) unless it was legally permitted as an ADU prior to January 1, 2020. JADUs shall not be used for short-term rental/lodging purposes (30 days or less) in any circumstance.

A.2.E Dwelling Unit Separation Requirements

CA GOV § 66323(d)

For purposes of any fire or life protection ordinance or regulation, an Accessory Dwelling Unit shall be considered a separate or new dwelling unit. For purposes of any fire or life protection ordinance or regulation, a Junior Accessory Dwelling Unit shall not be considered a separate or new dwelling unit. ADUs and JADUs shall both have separate exterior entrances.

A.2.F Foundation

All ADUs shall be constructed on a permanent foundation.

A.2.G Relationship to SB 9

HCD ADU Handbook (as amended March 2026) § “Senate Bill 9 (SB 9) (Chapter 162, Statues of 2021)”

ADU/JADU units may be combined with SB 9 projects. In no case shall more than four units, inclusive of ADU/JADU units, be permitted on an existing lot. In the case of a lot with a proposed SB 9 urban lot split, no resultant lot shall individually exceed two dwelling units, inclusive of ADU/JADU units.

A.3. Maximum Number

A.3.A. Single-Family or Halfplex Developments

CA GOV § 66323(a), subdivisions (1) through (2)

The following ADUs (potentially totaling three ADUs) may be permitted on any lot developed with a single-family dwelling or halfplex within a zone as specified in Section A.2.B:

• One (1) detached, new construction ADU, and

• One (1) junior accessory dwelling unit (JADU), and

• One (1) of the following three options:

  • New construction attached ADU, or

  • Attached conversion ADU, or

  • Detached conversion ADU

A.3.B. Conversion ADUs for Multifamily Dwellings

CA GOV § 66323(a), subdivision (3)

Properties developed as multifamily may have up to 25% of total unit count in ADUs or one unit, whichever is greater, converted from existing non-living space. Non-livable space includes, but is not limited to, on-site offices, storage rooms, boiler rooms, passageways, attics, basements, or garages.

A.3.C. New Construction ADUs for Multifamily Dwellings

CA GOV § 66323(a), subdivision (4)

In addition to allowances provided in Section A.3.B, multifamily dwellings may have the following additional ADUs:

1. New Construction. New construction multifamily projects may have up to two (2) new construction detached ADUs. Such ADUs must be detached from the primary multifamily structure.

2. Existing Multifamily Projects. Properties developed as multifamily as of January 1, 2025, may have new construction detached ADUs at a quantity not to exceed eight or the number of existing dwelling units as of January 1, 2025, whichever is less. This is in addition to multifamily ADUs permitted by conversion.

A.4 Maximum Size

A.4.A Detached, New Construction ADUs

CA GOV Title 7, Division 1, Chapter 13, Article 2

Detached, new construction ADUs pursuant to Sections A.3.A or A.3.C. are limited to 1,200 square feet.

A.4.B. Junior ADUs

CA GOV § 66333(d) & 66323(a)(1)(A)

JADUs are limited to 500 sq. ft. of space within the proposed or existing primary dwelling (including attached garages or attached storage areas).

An additional 150 sq. ft. of space may be permitted for ingress/egress for JADUs converted out of existing space. For example, if a second story from a single-family dwelling is converted into a JADU, a stairwell of not more than 150 square feet could be added, among other types of ingress and egress configurations that comply with the local building standards

A.4.C. Attached, New Construction ADU or Conversion ADU

CA GOV § 66333(d) & 66323(a)(1)(A)

An Attached, New Construction ADU is limited to the greater of the following:

1. 50% of the habitable sq. ft of the primary dwelling

2. For a studio or 1-bedroom ADU: 850 sq. ft.

3. For an ADU with 2 or more bedrooms: 1,000 sq. ft.

Conversion ADUs are limited to the existing space or structure on the subject property. An additional 150 sq. ft. of space may be permitted for ingress/egress for ADUs converted out of existing space. For example, if a second story from a single family dwelling is converted into an ADU, a stairwell of not more than 150 square feet could be added, among other types of ingress and egress configurations that comply with the local building standards.

A.4.D. Subordination to Primary Dwelling

CA GOV § 66321(b)(3)

1. For purposes of local classification, ADUs may not exceed the square footage of the existing primary dwelling.

2. If a new dwelling is proposed that is larger than an existing primary dwelling, the existing primary dwelling shall be reclassified as an ADU and the new dwelling shall be classified as the new primary dwelling.

3. If an existing primary dwelling is less than 800 square feet in size and a new larger dwelling of up to 800 square feet is proposed, the existing dwelling will be considered an accessory dwelling and the new construction dwelling will be considered a new primary dwelling per local classifications only. In such circumstances, to comply with State ADU law and to allow an ADU per CA GOV § 66323(a)(2), a free Zoning Verification Letter shall be issued to memorialize the development of the new primary dwelling (per local classifications) and the application of State ADU standards on such new dwelling, including reduced setbacks, ADU development impact fees, and more restrictive height limitations.

A.5 Amenities

A.5.A Bathrooms

CA GOV § 66313(a) & CA CBC § 1208.4

1. ADUs. All ADUs must have separate bathroom facilities from the primary dwelling.

2. JADUs. JADUs may have either separate or shared bathroom facilities with the primary dwelling. JADUs with shared bathroom facilities within the primary dwelling are permitted subject to property owner occupancy on the subject property, a recorded deed restriction, a separate exterior entrance from the primary dwelling, and an interior entry provided to the main living area of the primary dwelling to access the shared bathroom facilities.

A.5.B. Kitchens

CA GOV § 66313(a) & CA CBC § 1208.4

1. ADUs. All ADUs shall have a “full kitchen,” as defined in Chapter 7.3 of the Zoning Code.

2. JADUs. All JADUs shall have either an “efficiency kitchen,” as defined in Section A.2.B.4 or “full kitchen,” as defined in Chapter 7.3 of the Zoning Code.

A.5.C. Parking

CA GOV § 66322(a) & CA GOV § 66314(d)(10) & HCD ADU Handbook (amended March 2026) § “Are certain ADUs exempt from parking requirements?”

One (1) parking space shall be provided for new construction detached ADUs over 800 square feet in size accessory to single-family or halfplex developments, except that parking is not required where:

1. The accessory dwelling unit is located within one-half mile walking distance of public transit.

2. The accessory dwelling unit is located within an architecturally and historically significant historic district.

3. When on-street parking permits are required but not offered to the occupant of the accessory dwelling unit.

4. Where there is a car share vehicle located within one block of the accessory dwelling unit.

5. A garage, carport, uncovered parking space, or covered parking structure is demolished or converted in conjunction with the construction of an accessory dwelling unit at least partially within the footprint of the former parking space or structure.

New construction detached ADUs that do not exceed 800 square feet and ADUs of any other type do not require parking.

A.6 New Construction ADU Standards

A.6.A. Required Setbacks

CA GOV § 66323(a), subdivisions (1) through (4) & CA GOV § 66321(b)(3) & HCD ADU Handbook (amended March 2026) § “Setbacks”

The following setback requirements shall apply to ADUs accessory to single-family, halfplex, or multifamily developments:

1. Front Yard. For new construction ADUs over 800 square feet in size, the same front yard setback as required for a primary dwelling or multifamily dwelling, as applicable, in the same zoning district shall be required. For new construction ADUs 800 square feet in size or less, no front yard setback is required.

2. Interior Side & Rear Yard. 4 feet.

3. Easements. Notwithstanding subdivisions (1) and (2), all ADUs shall be located outside of recorded public easements pursuant to Section 5.2.0.B of the Zoning Code.

A.6.B. Maximum Building Height to Peak

CA GOV § 66321(b)(4)

1. Detached Accessory to Single-Family or Halfplex. 16 feet, except that 18 feet may be allowed if the ADU is either:

   1. Located within located within one-half mile of a major transit stop pursuant to CA PRC §21155, or
   2. Proposed at a height to allow a roof pitch consistent with the primary dwelling. Documentation shall be provided demonstrating both the existing roof pitch of primary dwelling and proposed ADU.

2. Attached Accessory to Single-Family or Halfplex. 25 ft. or the maximum allowable height of the primary dwelling, whichever is less.

3. Detached in a Multifamily Project. 18 feet.

4. Measurement. Height limitations for ADUs, as mandated by State law or as provided herein, shall be measured to peak.

A.6.C. Maximum Number of Stories

HCD ADU Handbook (amended March 2026) § “Height Requirements”

The maximum number of stories for a new construction ADU shall be limited by the maximum building height as provided in Section A.6.B.

A.6.D. Attached Non-Habitable Square Footage

All non-habitable square footage attached to a detached ADU accessory to single-family/halfplex or duplex shall be subject to development standards for Residential Accessory Structures as provided in Table 5.10.A of the Zoning Code. All non-habitable square footage attached to a multifamily ADU shall be subject to Multifamily Residential Development Standards as provided in Table 5.8.B of the Zoning Code.

Frequently Asked Questions

What isn’t an ADU or JADU?

• Detached guest houses, or similar, that include conditioned space that may be intended for occasional overnight use but does not contain cooking facilities (i.e., neither a full kitchen nor an efficiency kitchen).

• Second Dwelling Unit (SDU). While SDUs may look similar to ADUs, and State requirements provide similar side and rear setbacks for both types of dwellings, there are notable differences. SDUs are only permitted on properties that are eligible to utilize Senate Bill 9 (SB-9) provisions. Additionally, SDUs are subject to the same development standards as primary dwellings (except for size limitations), meaning they can be taller, have multiple stories, and trigger full Development Impact and Affordable Housing Ordinance fees.

• Tiny Homes, or similar ‘homes on wheels’ (THOWs). Any temporary living quarters (Recreational Vehicle, ‘Housecar’ or similar) that is regulated by the California Department of Motor Vehicles is not permitted as a dwelling unit in Sacramento County, except when parked at a permitted Mobile Home Park. All dwelling units must be placed on a foundation and meet residential building standards.

Is an ADU Allowed on my Property?

Any property developed with a primary residential use is permitted to have ADUs within zones listed in Section A.2.B.

Can I have an ADU or JADU in the Agricultural-Residential or Agricultural Zones?

No, ADUs and JADUs are not permitted in the Agricultural-Residential (AR) ¹ or Agricultural (AG) zones as they are not “single-family residential” or “mixed-use” zones. For options for additional dwellings in these zones, please see Zoning Code allowances for “Agricultural Accessory Dwellings” in Section 3.9.3.C or “Farmworker Housing” in Section 3.5.2.C.

Can I Use my ADU or Junior ADU as a Short-Term Rental?

An ADU cannot be used for short-term rental activity unless it was a legally permitted ADU prior to January 1, 2020. JADUs and Guest Houses cannot be used for short-term rental activity in any circumstance.

What if I want to Build an ADU or JADU that Doesn’t Meet Standards?

ADUs and JADUs must meet standards provided in this Appendix. Deviations are not permitted per Section A.2.A.

Will Converting an Existing Accessory Structure to an ADU Require a Building Permit?

Yes. A conversion of this type is considered a change in use under the building code and requires the structure to be brought into compliance with current residential building standards. See the information provided by the Building Permits and Inspections Division at https://building.saccounty.gov/.

Want to skip the hassle of designing your own ADU? Check out our Shelf Ready ADUs!

Thanks to a grant awarded to the County by the State Department of Housing and Community Development (Local Early Action Planning “LEAP” Grant), the County has a selection of detached ADU plans available for use on any property eligible for an ADU.

The “Shelf Ready” ADU plans offered through the program include a 460-square foot studio/one bedroom unit, an 870-square foot two-bedroom unit, a 1,000 square-foot two-bedroom unit, and a 1,184 square-foot three-bedroom unit. For more details, visit https://development.saccounty.gov/us/en/building-permits-inspection/news/shelf-ready-adu-plans-now-available.html.

What fees should I expect for a new ADU?

Fees for ADUs are project specific and can vary significantly from site to site. Further, fees can come not only from the County, but from other agencies involved in the building process, such as the Sacramento Municipal Utilities District (SMUD), water districts, and local fire departments.

For any project, you should expect to pay for building permit fees and development impact fees. For information on building permit fees, you can contact Building Permits and Inspection (BPI) Division at (916) 875-5296. For an estimate of applicable development impact fees, you may contact the Site Improvement and Permits Section (SIPS) of County Engineering for assistance. For information on how to request a development impact fee estimate, visit this page: https://development.saccounty.gov/us/en/county-engineering/sips/development-impact-fees.html.

I’d like to Learn More about Requirements for Solar Panels, Utility Service Requirements, and Other Topics.

The California Department of Housing and Community Development (HCD) has developed a helpful handbook that provides a thorough FAQ of developing ADUs and JADUs in California. The handbook is available by going to www.hcd.ca.gov, choosing ‘Accessory Dwelling Units,’ and then ‘ADU Handbook’.

Footnotes

1. Options for ADUs may be available in the AR zones within urban census tracts under Senate Bill 9 (SB 9) provisions. ↩