Skip to main content

Development Services

Accessory Dwelling Unit/Junior Accessory Dwelling Unit

 ADU/JADU Updates |March 2024

**New!! View the regulations outside the Coastal Overlay Zone effective March 15, 2024, including a new accessible bonus ADU allowance and new JADU location requirements.**

  • The San Diego Housing Commission’s (SDHC) Accessory Dwelling Unit (ADU) Finance Program helps homeowners with low income in the City of San Diego build ADUs on their property. The program provides financial assistance through construction loans and technical assistance that helps homeowners understand and complete the process of building an ADU. Learn more
  • Have questions about building an ADU on your property? Schedule a free virtual Planning and Zoning appointment.
  • Want to legalize your unpermitted ADU? Learn how
  • ADUs in the non-appealable areas of the Coastal Overlay Zone are now eligible for Process 1 review and approval. Learn more.

Accessory Dwelling Unit

An Accessory Dwelling Unit or ADU is an attached or 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 must include permanent provisions for living, sleeping, eating, cooking and sanitation on the same lot as the primary residence.​

Junior Accessory Dwelling Unit

A Junior Accessory Dwelling Unit or JADU is a unit that is no more than 500 square feet in size and contained entirely within a single-family residence located in a single-family zone. A JADU may include separate sanitation facilities or may share sanitation facilities with the existing structure. The JADU or single-family residence must be owner-occupied.​

Permit Application Process and Requirements

A Building Permit is required to create an ADU or JADU. There are no exemptions. Depending upon the number of dwelling units created by the ADU(s), either a Combination Building Permit or a Building Permit will be issued. If your property is within the Coastal Overlay Zone, please see the Coastal ADU Webpage.​

Apply for a Building Permit

A tiny home in a backyard next to a fire pit

ADU vs JADU Comparison​

Allowable LocationsSingle, Multiple, and Mixed-Use Zones, Planned Districts Ordinance Zones​Single Residential Zones
How many are allowed?​
  • 1 for single-dwelling zones​
  • 2+ for multiple dwelling unit zones​
Size150 - 1200 square feet​150 - 500 square feet
Attached or detached?​May be attached or detached from a dwelling unit​Must be a conversion or attached to an existing or proposed dwelling unit
ParkingNone except near the beach (Beach Impact Area)​None Required
Agreements RequiredNoneJADU Agreement
BonusAdditional ADUs may be proposed as part of the Bonus ADU ProgramJADUs are not part of the ADU Bonus program

Two-unit accessory dwelling unit under construction

ADU Bonus Program​​

If your property is a Sustainable Development Area (check your property with ZAPP), one additional non-deed restricted bonus ADU is allowed for every qualifying on-site deed-restricted ADU to very low-, low- or moderate-income households for 15 years (Table 141-03A). The maximum number of ADUs is only limited by the maximum floor area ratio and maximum lot coverage requirements of the underlying zone.​

Outside of sustainable development areas, where a project proposes qualifying on-site deed-restricted ADUs (Table 141-03A), the maximum number of bonus ADUs is one.​

Please see §141.0302(c)(2)(G) for program details.​

Woman in a wheelchair using a ramp

Accessible Bonus ADU

In addition to the bonus affordable ADU regulations above, if two Affordable ADUs are provided, you may be eligible for a bonus accessible ADU.​

Accessible units must meet the requirements of Chapter 11A of the California Building Code and must be located on an accessible route as defined by the California Building Code.​

Setback Compliance

Construction of new detached structures where a new structure is proposed as an ADU must comply with the Front and Street-Side Setbacks of the Zone (check your property’s Zone using ZAPP). The ADU may encroach into the Side and Rear Setbacks of the Zone, including up to the Property Line in some cases.​

If the side or rear property line are next to another premises that is residentially zoned or developed with exclusively residential uses, an ADU with a structure height that exceeds 16 feet or is multi-story must observe a 4-foot setback on the sides and rear.​

Residential base zone setbacks can be found on §131.0422.

Short ADU

No setback is necessary on the rear and side yard from the property line if the building height is under 16 feet.​

Tall ADU

4' setback from property lines on required side yards and rear yards if ADU / JADU height exceeds 16 feet and it is next to residential.​


ADU may encroach into the side and rear yard setbacks.

Encroachments such as exterior staircases, balconies, second-story decks, and roof decks may NOT encroach into setbacks with the ADU.


Frequently Asked Questions

What is my site zoned as?

You may check your property’s Zone using ZAPP.

Do ADUs count towards the floor area ratio?

ADUs count towards gross floor area and floor area ratio calculations.

Can I place an ADU in my front yard?

ADUs must conform to the front and street side yard setbacks of the Zone.

If a garage is converted into a Junior Accessory Dwelling Unit (JADU), do you need to provide replacement parking?

Replacement of parking is not required unless the site is located in the Beach Impact area of the Parking Impact Overlay Zone and is outside of a Transit Priority Area. In this case one replacement parking space is required, unless any of the following apply:

  • The ADU or JADU is 500 square feet or less;
  • The premises is located within a historical district that is a designated historical resource;
  • The ADU or JADU is attached to the proposed or existing primary dwelling unit or accessory structure;
  • The premises is located with a residential permit parking district;
  • There is a car share vehicle located within one block of the premises.

How much will my ADU cost in total?

Fees vary and are calculated depending on what the project is proposing. Applicants are encouraged to review Information Bulletin 501 for the schedule of construction permit fees.

Do ADUs count towards density?

No. ADUs are considered supplemental to the primary use on the site and therefore not included in density.

What is the maximum height permitted for my ADU/JADU

ADUs and JADUs must conform to the maximum permitted height of the applicable Zone.

Can I maintain my driveway after converting my garage into an ADU?

In some cases, a driveway may need to be closed. If a garage conversion or addition of an ADU or JADU causes an existing driveway to be less than 18 feet long measured from the back of the sidewalk inward to the parcel, the driveway must be closed.

Does my ADU / JADU require a fire sprinkler system?

Detached ADUs are only exempt from sprinkler protection when the primary dwelling unit is not sprinkler protected, and the detached ADU(s) is considered a Group R-3 occupancy. Attached ADUs always require sprinkler protection when the primary dwelling unit is sprinkler-protected. Please see RESD-3-4 for more information.

Can decks or open exterior staircases encroach into the side or rear setbacks if they are for the ADU?

No. Decks and open exterior staircases must conform to the side or rear setback of the Zone. If the staircase is enclosed as conditioned habitable area and included in the ADU square footage, the staircase is considered part of the ADU and may encroach in the side or rear setback in accordance with SDMC 141.0302(c)(2)(G).

Can I use my ADU as an AirBnB / vacation rental?

No. An ADU or JADU may not be used for a rental term of less than 31 consecutive days.

Does my ADU require refuse, organic waste, and recyclable materials storage?

Yes. Development that generates refuse, organic waste, and/or recyclable material must provide for the collection and management of these materials pursuant to Chapter 6, Article 6. Development must provide adequate storage space for these materials as set forth in SDMC Sections 142.0801 through 142.0830.

Does my ADU / JADU require solar panels?

Newly constructed ADUs are subject to the California Energy Code requirement to provide solar panels if the unit(s) is a newly constructed, non-manufactured, detached ADU. Per the California Energy Commission (CEC), the panels can be installed on the ADU or the primary dwelling unit. JADUs do not require solar panels.

Is my ADU exempt from inclusionary housing fees?

No. ADUs are considered dwelling units and are subject to the Inclusionary Housing Regulations.

What is the distance required between my proposed ADU and an existing structure?

ADUs must comply with all requirements in the California Building Standards Code, including requirements for fire separation distance. ADUs are not subject to zoning building spacing regulation outlined in SDMC 131.0450.

Is parking required for new ADUs?

Parking is not required for new ADUs except for garage conversions in the Beach Impact area of the Parking Impact Overlay Zone that are outside of a transit priority area.

When an ADU is proposed on top of a garage or carport, is the garage or carport square footage included in the maximum 1,200 square feet of the ADU?

No. The garage or carport space beneath the ADU would not be included in the ADU square footage but may be included in the overall gross floor area of the site.

If an ADU is located on posts, is the ground floor exterior space included in the maximum 1,200 square feet of the ADU?

No, but that area may be included in the total gross floor area of the site in accordance with SDMC 113.0234(b)(3).