Check your property's zoning, browse designs & get contractor estimates for your ADU project:
City Hint: The City of Tustin permitted a total of 11 ADU projects in the past year of 2020.
Number of ADUs allowed:
According to state law, all single-family homes are allowed at least one Accessory Dwelling Unit. Additionally, single-family lots which are owner-occupied may create one Accessory Dwelling Unit and one Junior Accessory Dwelling Unit. Also, multi-family lots may now add one ADU per every four existing residential units, so long as they were legally established.
Types of ADUs allowed:
Detached ADU, Attached ADU, Junior ADU are permitted. ADUs may be new construction or converted from existing space. JADUs must be converted from existing space.
Single family and multi-family residential properties will not be subject to the minimum lot size of the underlying zoning district or by ordinance for ADU projects. ~ According To AB68
Single-family and multi-family Lots will be approved to construct up to 850 sq.ft. for a one bed ADU or up to 1,000 sq.ft. for a two bed ADU, regardless of the underlying zoning standards of the property. A Junior Accessory Dwelling Unit up to 500 sq.ft. is approved. The minimum size of any living unit (including Accessory Dwelling Unit (ADU)s and Junior Accessory Dwelling Units) is 150 sq.ft. according to California Residential Code. ~ According To AB68
The maximum required setback for a detached new construction Accessory Dwelling Unit shall be no more than 4 ft from the rear and side property lines. Setbacks will not be required for Accessory Dwelling Units and Junior Accessory Dwelling Units converted from existing space that was legally eastablished. Attached Accessory Dwelling Units and conversions from existing space to be expanded will be required to comply with the setbacks of the underlying zone. ~ According To AB68
Lots which convert an existing garage to an ADU or Junior Accessort Dwelling Unit (JADU) will not be subject to replacement parking requirements. ~ Updated: State Law AB-68
Accessory dwelling units shall not be required to provide fire sprinklers unless they are also required for the primary dwelling. ~ State Standards
Shape, materials and style:
Specific design styles and restrictions are not specified under State Standards. Passageways shall not be required in conjunction with the construction of an accessory dwelling unit. ~ State Standards
The maximum height of an ADU is not specified in the state standards. If ADU maximum height is not established locally, the height limitations of the underlying zone shall apply. ~ State Standards
The municipality shall provide a ministerial review process which is not based on a discretionary approval for an ADU. The process shall take no less than 120 days. Valid applications submitted for ADUs, if not approved or denied within 120 days from submission, shall be considered approved. ~ State Standards
Number of Bedrooms:
No maximum number of bedrooms is established other than that implied by the maximum size of an ADU allowed. ~ State Standards
Owner-occupancy will not be required for new Accessory Dwelling Units (conversion and new construction) built between 2020 and 2025. ~ According To SB13
Connection and utility fees shall be reasonable, and shall not be disproportionately higher than those to develop primary dwellings, so as not to deter the development of ADUs. If a private sewage disposal system is used, such as a septic system, review and approval by a local health officer may be required. ~ State Standards
*** Beginning in 2020, according to state law, all residential zoning districts, including single-family and multi-family, are allowed to build Accessory Dwelling Units. ***
ADUs can be established in zones such as R1 – Single Family Residential and PC RES – Planned Community Residential (varies by development). From there, if a single family home is establish in R2 – duplex residential or R3- Multiple Family Residential, they may use this same provision, however this would not apply to any existing duplex or multiple family dwelling within the same district.
Residential Building Code:
The California Building Code (CBC) 2019 is adopted.
This estimate is based on recently completed projects in the area and is inclusive of all typical soft costs such as permitting, design and engineering fees.