This Information Bulletin provides guidance on the City of San Diego's requirements for obtaining a Building Permit to construct Accessory Dwelling Units (ADU) and Junior Accessory Dwelling Units (JADU). General Regulations for ADUs and/or JADUs can be found in San Diego Municipal Code Chapter 14, Article 1, Division 3.

Accessory Dwelling Unit (ADU)

What is an ADU?

An Accessory Dwelling Unit (ADU) is an attached or detached residential dwelling unit that:

• Is 1,200 square feet in size or less; and
• Provides complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking, and sanitation; and
• Is located on a lot with a proposed or existing single-dwelling unit or multiple-dwelling units.

Development of multiple ADUs, including Bonus ADUs, are required to comply with the base zone development regulations limiting structure height, lot coverage, and maximum floor area ratio.  

ADUs Allowable Locations

ADUs are permitted in Zones where Use Regulation Tables identify ADUs as allowable Limited Uses. Generally, ADUs are allowed in Zones that permit Residential Uses.

• Base Zone Designations: Use Regulation Tables in SDMC Chapter 13, Article 1, Divisions 1 through 7
• Planned District Ordinance Zone Designations: Use Regulation Tables in SDMC Chapter 15, Articles 2 through 20
• Find your Zone Designation by visiting the Zoning and Parcel Information Portal (ZAPP)

Number of Allowed ADUs

1. Single Dwelling Unit Zone A single dwelling unit zone is a zone that allows a maximum of one dwelling unit on a single lot. Dwelling units permitted within single dwelling unit zones:
   • 1 Single Primary Dwelling Unit; and
   • 1 Accessory Dwelling Unit detached from an existing or proposed dwelling unit; and
   • 1 Accessory Dwelling Unit converted from the existing space of a single dwelling unit or attached accessory structure; and
   • 1 Junior Accessory Dwelling Unit
2. Single Dwelling Unit Zone Exception for Existing Multi-Dwelling Unit Buildings Within single dwelling unit zones, where a legally permitted, previously conforming multi-dwelling unit structure exists, ADUs may be constructed in accordance with the multiple-dwelling unit zone provisions outlined below in Multiple-Dwelling Unit Zones.
3. Other Allowances In addition to the Primary and Accessory Dwelling Units, Guest Quarters and Non-Habitable Accessory Structures are also allowed.

ADUs proposed in conjunction with the City’s implementation of California Senate Bill 9 (2021-2022) are subject to the provisions in SDMC Chapter 14, Article 3, Division 13 (reference §143.1305(c)). If the project proposes an Urban Lot Split in accordance with §143.1315, a signed affidavit from the Record Owner will also be required.

Multiple-Dwelling Unit Zones

A multiple-dwelling unit zone is a zone that allows more than one dwelling unit on a single lot.

1. Conversions or Interior Alterations of Existing Structures
   • Existing Habitable Area: The maximum number of ADUs permitted within the habitable areas of an existing multiple-dwelling unit structure is 25% of the total number of existing dwelling units. One ADU is permitted where the percentage calculation yields less than one ADU.
   • Existing Non-Habitable Area: The number of ADUs permitted within the non-habitable areas of an existing multiple-dwelling unit structure is unlimited. Examples include storage rooms, boiler rooms, passageways, attics, basements, and garages.
2. Construction of New Attached or Detached Structures A maximum of two attached or detached ADUs are permitted on premises with an existing or proposed multiple-dwelling unit structure. The two ADUs may be within one structure or two separate structures.

3. Multiple-Dwelling Unit Zones with an Existing Single-Dwelling Unit Building Within multiple-dwelling unit zones, where a legally permitted single-dwelling unit structure exists, ADUs may be constructed in accordance with the Multiple-Dwelling Unit Zone provisions outlined above.

   The premises may construct the ADU(s) without a requirement to construct any other additional primary dwelling units.

ADU Size Regulations

1. The minimum gross floor area for an attached or detached ADU is 150 square feet.
2. The maximum gross floor area for an attached or detached ADU is 1,200 square feet.
3. The gross floor area of an ADU is included in the total gross floor area of a premises and is subject to the floor area ratio of the underlying zone. However, the floor area may be exceeded to allow one ADU that is up to 800 square feet.
4. Minimum room dimension requirements contained within the California Building Standards Code are applicable.
5. The conversion of an existing accessory structure or a portion of the existing primary residence to an ADU is not subject to the 1,200-square-foot maximum gross floor area limitation.

ADU Setback Regulations

1. Conversions or Interior Alterations of Existing Structures - Where an existing structure is converted to an ADU, the ADU may continue to observe the setbacks of the existing structure.
2. Demolition and Reconstruction of Existing Structures - Where an existing structure is demolished and reconstructed as an ADU, the ADU may continue to observe the setbacks of the original structure. The reconstruction must be at the same location and to the same dimensions as the original structure.

3. Addition of Floor Area to Existing Structures - Where an addition to an existing structure is proposed for an ADU, the ADU must observe the Front Yard and Street Side Yard Setbacks of the Zone. The ADU may encroach into the Side Yard and Rear Yard Setbacks of the Zone, including up to the Property Line if the structure height is 16 feet or less, unless requirements in the California Building Standards Code apply, including requirements for fire separation distance, opening protection, allowable height, and allowable area.

   If the side or rear property line abuts 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 shall observe a minimum 4-foot Interior-Side Yard and Rear Yard setbacks.

4. Construction of New Detached Structures - Where a new structure is proposed as an ADU, the ADU must observe the Front Yard and Street Side Yard Setbacks of the Zone. The ADU may encroach into the Side and Rear Setbacks of the Zone, including up to the Property Line, unless requirements in the California Building Standards Code apply, including requirements for fire separation distance, opening protection, allowable height, and allowable area.

   If the side or rear property line abuts 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 shall observe a minimum 4-foot Interior-Side Yard and Rear Yard setbacks.

   Exterior staircases, decks, and balconies must conform to the base zone setback.

5. Front Yard and Street Side Yard Requirements - ADUs must observe the Front Yard and Street Side Yard Setbacks of the Zone. However, a maximum of one ADU of 800 square feet or less may encroach into the Front Yard or Street Side Yard Setback.

ADU Parking Regulations

1. No parking spaces are required for ADUs outside of the Coastal Overlay Zone. No parking is required within the Coastal Overlay Zone except if the property is located within the Beach Impact Area of the Parking Impact Overlay Zone and outside of a transit priority area. In this instance, one off-street parking space is required unless any of the following apply:
   • The ADU is 500 square feet or less;
   • The premises is located within a historical district that is a designated historical resource;
   • The ADU is attached to the proposed or existing primary dwelling unit or accessory structure;
   • The premises is located within a residential permit parking district;
   • There is a car share vehicle located within one block of the premises.
2. The conversion or demolition of a garage, carport, or covered parking structure does not require the replacement of parking spaces, except if the property is located in the Coastal Overlay Zone and within the Beach Impact Area of the Parking Impact Overlay Zone and outside of a transit priority area. If the construction of an ADU or JADU involves the conversion or demolition of a covered parking structure and the existing driveway curb is no longer compliant with City standards, the associated driveway shall be closed to the satisfaction of the City Engineer.
3. Where off-street parking spaces are provided, parking spaces may be within setback areas, and in any configuration, including tandem configurations and mechanical lifts.
4. Where off-street parking spaces are provided, parking spaces must be entirely within the property line of a premises, and must conform to the dimension standards of SDMC Chapter 14, Article 2, Division 5.

Other Regulations

1. The property owner is not required to live on-site.
2. An ADU may not be leased for a term of less than 31 consecutive days.
3. ADU(s) development is subject to Refuse, Organic Waste, and Recycle Material Storage Regulations in SDMC §142.0801. Development will need to conform to Table 142-08B enclosure square footage and screening requirements.
4. ADU(s) development exceeding four dwelling units is subject to the Mobility Choices Regulations in SDMC §143.1103.
5. Building Code Requirements - ADUs must comply with all requirements in the California Building Standards Code, including requirements for fire separation distance, opening protection, allowable height, and allowable area. These requirements may result in increased setback requirements for ADU development.
6. Landscape Requirements - If construction of an ADU or JADU would bring the total number of ADUs or JADUs on the premises to a total of two or more, two trees shall be provided on the premises for every 5,000 square feet of lot area, with a minimum of one tree per premises. If planting of a new tree is required to comply with this section, the tree shall be selected in accordance with the Landscape Standards of the Land Development Manual and the City's Street Tree Selection Guide and shall comply with the street tree requirements of SDMC §142.0409(a).
7. The Climate Action Plan Consistency Regulations apply to all projects that result in three or more total dwelling units on a premises (SDMC §143.1403).

ADU Fire Sprinkler Systems

Reference Technical Bulletin RESD 3-4 for fire sprinkler requirements in ADUs.

ADU Solar Photovoltaic Systems

1. 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.
2. ADUs constructed within existing space or as an addition to existing homes, including detached additions where an existing detached building is converted from non-residential to residential space, are not subject to the California Energy Code requirement to provide solar panels.

ADU Bonus Program

1. Within sustainable development areas, for every qualifying on-site deed-restricted ADU (Table 141-03A), one additional non-deed-restricted bonus ADU is allowed. The development must still comply with the maximum floor area ratio, maximum height, and maximum lot coverage requirements of the underlying zone.
2. Within sustainable development areas, where a Project proposes qualifying on-site deed-restricted ADUs (Table 141-03A), the maximum number of bonus ADUs is unlimited. The development must still comply with the maximum floor area ratio, maximum height, maximum lot coverage requirements, and other applicable development standards of the underlying zone.
3. 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.
4. Reference SDMC §141.0302(c)(2)(G) for program details.
5. In addition to the affordable ADU bonus, one additional market rate accessible ADU is allowed when at least two affordable ADUs are proposed on a premises in accordance with SDMC §141.0302(c)(2)(I). The bonus accessible ADU must meet the requirements of Chapter 11A of the California Building Code. The accessible ADU shall include at least one accessible bathroom, one accessible kitchen, and one accessible bedroom, and shall be located on an accessible route, as defined by the California Building Code.

Junior Accessory Dwelling Unit (JADU)

What is a JADU?

A Junior Accessory Dwelling Unit (JADU) is a dwelling unit that is not less than 150 square feet and no more than 500 square feet within an existing or proposed single dwelling unit or an attached garage on a residential single dwelling unit lot. A JADU may include separate sanitation facilities or may share sanitation facilities with the single dwelling unit. The JADU shall provide a kitchen or efficiency kitchen.

JADU Allowable Locations

JADUs are permitted in Zones where Use Regulation Tables identify JADUs as allowable Limited Uses. Generally, JADUs are allowed in Single Dwelling Unit Zones.

• Base Zone Designations - SDMC Chapter 13, Article 1, Divisions 1 through 7.
• Planned District Ordinance Zone Designations - Use Regulation Tables: SDMC Chapter 15, Articles 2 through 20.
• Find your Zone Designation by visiting the Zoning and Parcel Information Portal (ZAPP)

Number of JADUs Allowed

1. Single Dwelling Unit Zones A Single-Family Zone is a zone that allows a maximum of one dwelling unit on a single lot. Permitted within Single Dwelling Unit Zones:

• 1 Single Primary Dwelling Unit
• 1 Accessory Dwelling Unit
• 1 Junior Accessory Dwelling Unit

1 JADU may be constructed within an existing or proposed:

• Single Primary Dwelling Unit
• Garage attached to a Single Primary Dwelling Unit

Other Allowances: In addition to the Dwelling Units, Guest Quarters and Non-Habitable Accessory Structures are also allowable.

2. Multiple-Dwelling Unit Zones

• A Multiple-Dwelling Unit Zone is a zone that allows more than one dwelling unit on a single lot.
• JADUs are not permitted within Multiple-Dwelling Unit Zones.

JADU Size Regulations

1. The minimum gross floor area for a JADU is 150 square feet.
2. The maximum gross floor area for a JADU is 500 square feet.
3. The gross floor area of a JADU is included in the total gross floor area of a premises.
4. Minimum room dimension requirements contained within the California Building Standards Co are applicable.

JADU Parking Regulations

1. Where off-street parking spaces are provided, parking spaces may be within setback areas, and in any configuration, including tandem configurations and mechanical lifts.
2. Where off-street parking spaces are provided, parking spaces must be entirely within the property line of a premises and must conform to the dimension standards of SDMC Chapter 14, Article 2, Division 5.

JADU Regulations

1. A JADU shall maintain the same setback requirements of an existing or proposed Single Primary Dwelling Unit.
2. A JADU shall have a separate exterior entry from the Single Primary Dwelling Unit.
3. A JADU shall provide a separate independent kitchen or efficiency kitchen from a Single Primary Dwelling Unit.
4. A JADU may include separate independent sanitation facilities or may share sanitation facilities with an attached Single Primary Dwelling Unit or attached ADU.
5. Where a JADU exists on a premises, the property owner is required to live on-site.
6. The property owner may live in any of the on-site dwelling units.
7. A JADU may not be leased for a term of less than 31 consecutive days. A JADU may not be used for Transient Lodging.

JADU Fire Protection Systems

1. Where a primary dwelling unit is provided with a fire sprinkler system, the JADU will be required to install a fire sprinkler system. The JADU may be required to fire rate the walls that are shared with the primary unit, or ensure that the sprinkler system in the primary dwelling unit communicates with the sprinkler system in the JADU.
2. Where a primary dwelling unit is not required to provide a fire sprinkler system, a proposed JADU will not be required to install a fire sprinkler system. However, the JADU may be required to construct a fire rated wall when sharing a wall with an existing or proposed single-family dwelling when the JADU includes an independent kitchen and independent sanitation facilities.

JADU Solar Photovoltaic Systems

JADUs are not required to provide a solar photovoltaic system.

JADU Agreement Required

Before issuing a Building Permit, a Junior Unit Agreement is required that neither the primary dwelling unit nor the junior unit may be sold or conveyed separately and that the record owner shall reside in either the primary dwelling unit, ADU or JADU.

Permit Application Process and Requirements

Building Permit Requirement

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.

Refer to Information Bulletin 125 to confirm the appropriate permit type.

Coastal Development Permit Requirement

1. A Coastal Development Permit (CDP) is required for the creation of all ADUs and JADUs that are not completely contained in the existing primary structure or include increases in habitable area, or include conversion of non-habitable space within the Coastal Overlay Zone.
2. As of Sept. 7, 2022, ADUs and JADUs proposed in the non-appealable area of the Coastal Overlay Zone are eligible for a City-issued Coastal Development Permit, provided that specific administrative findings are made to ensure that the ADU/JADU(s) conform to the Local Coastal Program.
3. If the administrative findings outlined in §126.0708(c) are satisfied, the Coastal Development Permit shall be issued as a Building Permit in accordance with Process One as specified in §112.0502 and Chapter 12, Article 9, Division 2.
4. The creation of a JADU within the Coastal Overlay Zone does not categorically require a CDP. Qualifying JADU projects within the Coastal Overlay Zone meeting the exemption criteria of SDMC §126.0704 may be permitted without a CDP.

Other Permit Requirements

1. Single Primary Dwelling Units with ADUs or JADUs (R3 Occupancy Classifications): Project Submittal Manual Section 2A
2. Multiple-dwelling units with ADUs or JADUs (All Other Occupancy Classifications): Project Submittal Manual Section 2
3. Minimum submittal requirements for each ADU or JADU include the following:
   1. Plans / Calculations:
      1. Site Plan and Vicinity Map (See Information Bulletin 122).
      2. Floor Plans and Roof Plans.
      3. Elevations and Sections (as applicable).
      4. Structural plans and details.
      5. Structural calculations and/or truss calculations (as applicable).
      6. Title 24 Energy calculations.
   2. Forms
      1. General Application, DS-3032
      2. Water Meter Data Card, DS-16
      3. Storm Water Applicability Checklist, DS-560

Preapproved ADU Plans

Per California Assembly Bill (AB) 1332 (Carillo 2023), applicants may apply for a permit using preapproved plans. Applications that utilize preapproved plans will be subject to a 30-day review and must comply with the development regulations contained in the SDMC. Note: In order to utilize a preapproved plan, applicants must directly reach out to the ADU provider to find the cost to license the preapproved plan for their own ADUs. For a list of preapproved plans, please visit the Accessory Dwelling Unit/Junior Accessory Dwelling Unit webpage.

Applicants may also apply to have their plans preapproved for use by others. Applications for plan preapproval will be processed in accordance with the master plan production process outlined in Information Bulletin 114a. Once a plan is preapproved, it will be posted on the DSD website with the applicant's contact information alongside other preapproved plans.

Fees

1. For a complete list of all applicable fees, reference Information Bulletin 501 and visit the Fees page.
2. ADUs and JADUs are subject to payment of School Fees. For detailed information of when this fee applies, reference Information Bulletin 146.
3. Beginning Aug. 9, 2022, the General Plan Maintenance Fee applies to all ADU and JADUs.
4. ADUs are subject to Development Impact Fee requirements in accordance with SDMC §142.0640(b)(1).
5. Projects proposing more than one ADU will be required to pay the Regional Transportation Congestion Improvement Program Fees.
6. ADUs/JADUs are not exempt from the City’s Inclusionary Affordable Housing Regulations (SDMC Ch. 14, Article 2, Division 13). Projects proposing one or more ADU that results in 10 or more total dwelling units (or five or more total dwelling units in the Coastal Overlay Zone) are subject to Inclusionary Housing requirements.
   1. Projects that propose to pay the Inclusionary In Lieu Fee are subject to the requirements of §142.1306.
   2. Affordable ADUs proposed in accordance with §141.0302(c)(2)(D) are NOT exempt from the net building area calculations of the In Lieu Fee unless the units are deed restricted for 55 years at 60% of the area median income (or lower).  
7. Fee Payment Options
   1. Customers are encouraged to make online payments by e-check or credit card. Bank and processing fees apply. There are no minimum or maximum credit card transaction amounts when making payments online.
   2. Customers can also drop check payments into the payment drop-off safe located on the first-floor lobby of the downtown Development Services Center during business hours. All payments must be made out to “City Treasurer.”
   3. Customers can also request a Payments appointment to make credit card or check payments in person at the Development Services Center. With in-person payments, the minimum credit card transaction amount is $10, and the maximum is $99,999.99. Payments with an "SAP Invoice Number" are not accepted here. Instead, these invoices can be paid with the City Treasurer; Learn more.

How to Apply

Applications for Accessory Dwelling Units and Junior Accessory Dwelling Units are now being accepted in digital paperless formats through an Online Permitting Account.

Digital Application Portal

1. Navigate to the Development Services Application Portal.
2. For new Permit Applications, within the Building Applications section, select “Building Construction.”
3. For changes to existing issued Permits (under construction), request: “Construction Change to a Building Permit.”