Check your property's zoning, browse designs & get contractor estimates for your ADU project:
City Hint: The city permitted a total of 416 ADU projects in the past year of 2019, which makes it above average for ADU production compared to other cities statewide.
Number of ADUs allowed:
Single family Properties: Subject to standards, one ADU and one JADU may be allowed.
Multifamily Properties: Subject to standards (pages 2-4), two detached ADUs may be allowed. For a duplex, one attached ADU may also be allowed. For multifamily lots, a number of attached ADUs equivalent to up to 25% of existing units may also be allowed (for example, a building with 12 units may qualify for 3 attached ADUs).
Types of ADUs allowed:
Detached ADU, Attached ADU, Junior ADU are allowed. Accessory Dwelling Unit (ADU)s may be new construction or converted from existing space. Junior ADUs must be converted from existing space.
Accessory Dwelling Unit projects on single family or multi-family residential lots will not be subject to the minimum lot size of the underlying local zoning code or by special ordinance. ~ AB68
Single Family Lots < 9,000 sq. ft:
-Detached: 1,000 sf maximum.
-Attached: Size can be up to 800 sf OR up to 50% of the primary residence area without exceeding 1,000 sf. Example: For an 1,800 sf home, a 900 sf attached ADU is allowed.
Single Family Lots >= 9,000 sq. ft:
-Detached ADU: 1,200 sf maximum.
-Attached ADU: Size can be up to 800 sf OR up to 50% of the primary residence area without exceeding 1,200 sf. Example: For an 2,400 sf home, a 1,200 sf attached ADU is allowed.
JADU: 500 sq. ft
Multifamily Lots: Detached ADU: 800 sf maximum
Attached ADU: 800 sf maximum
Attached ADU: Same setback requirements as apply to the main dwelling unit.
- Must be set back 45 feet minimum from front property line.
- Rear/side setbacks less than 3 feet may be subject to fire mitigation measures, see p. 4.
- A second story OR new ADU with greater than 40% rear yard coverage must be set back 4 feet from both rear and side property lines.
Multifamily Residences: Attached ADU:
-Setbacks not applicable as the attached ADU is limited to a conversion of existing nonlivable space.
- Must be in the rear yard or 45 feet from the front property line.
- Rear/side setbacks: Minimum 4 feet, allows for up to 1-foot projection for eaves
- A second story must be set back 4 feet from both rear and side property lines.
Parking space location: If you are required to provide a parking space, it must be located on a surface free of mud or dust. It may be located within the front and side setbacks of the property, with a minimum driveway length of 18 feet.
Parking requirements after a garage conversion: If you converted a garage to an ADU, replacement parking for the main home is no longer required.
No parking is required for an ADU that meets any of the following criteria.
1. The ADU is located within .5 mile of a public bus stop or rail station (see www.vta.org), and the path of travel is publicly accessible.
2. The ADU is part of or within the primary residence or existing accessory building.
3. The ADU is on a street that requires on-street parking permits, but the permit has not been offered to the occupant of the ADU.
4. The ADU is located within one block of where a motor vehicle provides hourly and daily service as part of a regional fleet operated by a public
agency or publicly-leased motor-vehicle-sharing organization.
5. The ADU is located within a historic district listed in the City’s Historic Resources Inventory.
Fire sprinklers are required if required in the primary home.
Shape, materials and style:
Detached units do not need to meet any specific design standards. Attached ADUs and detached ADUs on properties listed on the Historic Resources Inventory must incorporate architectural style and elements of the primary dwelling.
Sill height for any openings must be a minimum 5 feet from the floor for walls nearest to rear and side property lines.
Single Family: Attached ADU: Same height limitations as apply to the main dwelling unit.
Detached ADU: One story: 18 feet maximum. Two-story: 24 feet maximum
If the property includes a JADU, height of a detached ADU is 16 feet maximum per state law.
Multifamily: Attached ADU: Limited to a conversion of existing non-livable space and must maintain existing height.
Detached ADU: 16 feet maximum per state law
Ministerial review process. Allowed by right in accordance with zoning and building code.
Number of Bedrooms
Up to two bedrooms are allowed, and the maximum bedroom size is 400 sf
Owner-occupancy will not be required for new ADUs (conversion and new construction) built between 2020 and 2025. ~ SB13 Update
Local health officer approval where a private sewage disposal system is being used, if required. (State requirements)
Front Door for Attached Unit cannot be on same street-facing façade as that of primary residence, unless all other locations for placing front door would require a pathway that is unobstructed, clear to the sky and extending from a street to the front door. (20.30.150.K.3)
Rear Yard Coverage:
Note that the current rule of a maximum 40% coverage of the rear yard will continue to be required.
*** Beginning in 2020, according to state law, all residential zoning districts, including single-family and multi-family, are allowed to build Accessory Dwelling Units. ***
Please refer to the following Zoning Code Section for information related to ADU's: https://library.municode.com/ca/san_jose/codes/code_of_ordinances?nodeId=TIT20ZO_CH20.30REZODI_PT2USAL_20.30.150SEUN -- You could also review this webpage: http://www.sanjoseca.gov/documentcenter/view/78534
Storage / Closet
Maximum of 60 square feet of closet space allowed per entire ADU.
Rear Yard Coverage
The cumulative total of the rear yard covered by detached unit, accessory buildings, and accessory structures cannot exceed 40%. (20.30.150.J.7)
Kitchen / Bath
(a) Kitchen required (sink, food storage, permanent cooking facilities)
(b) Maximum one bathroom
Attached – (1) Share a wall or (2) have integral roof structure with primary residence, and separated by no more than 10 feet. (20.30.150.J.2)
Detached - (1) Must be located in the rear yard, with a 6-foot separation from the main residence. (20.30.150.J.3 & 4) (2) May be attached to detached garage, if it meets Building and Fire Code; but may not be attached to other accessory buildings.(20.30.150.J.6)
PARKING EXEMPTION (20.30.150.I): No additional parking shall be required for a Secondary Dwelling that meets any of the following criteria:
The Secondary Dwelling is located within one-half (1/2) mile of, and has a path of travel that is always publicly accessible to a Site containing an existing public rail-transit station or at least one (1) public bus route with a frequency-of-service interval of fifteen (15) minutes or less during the morning and afternoon peak commute periods.
The Secondary Dwelling is located within a Historic District identified in the City’s Historic Resources Inventory as defined in Chapter 13.48 of Title 13 this Municipal Code.
The Secondary Dwelling is part of the existing primary residence or part of an existing Accessory Structure.
When on-Street parking permits are required but not offered to the occupant of the Secondary Dwelling.
When there is a motor vehicle that is operated as part of a regional fleet by a public agency or publicly leased motor-vehicle-sharing organization and provides hourly and daily service located within one (1) block of the Secondary Dwelling.
Residential Building Code:
The California Building Code (CBC) 2019 is adopted.
City of San Jose, Development Services Permit Center
200 E Santa Clara St., San Jose, CA San Jose, CA 95113
ADU Design Library
Browse hundreds of models to find the right fit for your property.
ADU Model 400 sqft
W 20 ft L 20 ft
ADU Model 720 sqft
W 20 ft L 20 ft
ADU Model 594 sqft
W 27 ft L 22 ft
"Housable has been a great resource regarding my ADU project. I purchased both the Property and Design Reports. In both cases, they delivered as promised and on time."Ed in Corona, CA
"My experience with Housable was exceptional. The team was extremely helpful and responsive. I am very satisfied and happy to have used these services. As a home owner I do not know the construction lingo or process but the Housable team very kind and helpful and patient with me. My expectations were exceeded. Thank you for everything."Monica H. in Oakland, CA
"The property report was great! Made me feel like my project is feasible."Alexandria in Santa Ana, CA
"My permits were APPROVED, thank you for all your hard work. I am in the process of meeting with contractors. "Mary S. in San Jose, CA
"I just wanted to let you know that the permit process has been completed and we are currently in the construction phase. The work you guys did was great and I will definitely be using this service again in the future. I will keep you guys updated on anything important. Thanks!"Patrick L. in Orange County, CA
SELECT ADU SIZE & TYPE
* upon completion of ADU
CONSTRUCTION COST ESTIMATE
* based on local average price per sqft
SELECT ADU SIZE & TYPE
Size: 500 sqft
Appreciation Estimate = (Base Value: $) / (Home's Living Space: sqft) * (ADU's Living Space: sqft)
Rental Estimate = (Rent Per Sqft: $4.18) * (ADU's Living Space: sqft)