Everything about building Accessory Dwelling Units in Irvine, CA
Check your property's zoning, browse designs & get contractor estimates for your ADU project:
Last Updated 09/20/21
Number of ADUs allowed:
Under state law, each single-family home may now create at least one Accessory Dwelling Unit. Owner occupied single-family properties may create one Accessory Dwelling Unit and one Junior Accessory Dwelling Unit (JADU). Multi-family properties, per every four existing residential units, may create one Accessory Dwelling Unit, so long as the existing units 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.
Lot size:
Single family and multi-family residential parcels will not be subject to the minimum lot size of the underlying zoning district or by ordinance for ADU projects. ~ AB68 & AB881 Update
ADU size:
Single-family and multi-family Parcels will be permitted to create up to 850 square feet for a one bedroom ADU or up to 1,000 square feet for a two bedroom ADU, regardless of the underlying zoning standards of the property. A Junior Accessort Dwelling Unit (JADU) up to 500 square feet is permitted. The minimum size of any living unit (including Accessory Dwelling Units and Junior Accessort Dwelling Unit (JADU)s) is 150 square feet according to California Residential Code. ~ AB-68
Detached units may be allowed up to 1,200 sq. ft.
Setbacks:
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 Unit (JADU)s 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
Parking:
Replacement parking shall not apply to lots which convert an existing garage to an Accessory Dwelling Unit or Junior Accessory Dwelling Unit. ~ According To AB68
A local agency shall not impose ADU parking standards for any of the following
(1) Accessory dwelling unit is located within one-half mile walking distance of public transit.
(2) Accessory dwelling unit is located within an architecturally and historically significant historic district.
(3) Accessory dwelling unit is part of the proposed or existing primary residence or an accessory structure.
(4) When on-street parking permits are required but not offered to the occupant of the accessory dwelling unit.
(5) When there is a car share vehicle located within one block of the accessory dwelling unit.
Fire Safety:
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
Height:
ADUs shall be allowed at least 16 ft in height. 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
Design review:
State Standards don't require any additional design review.
Number of Bedrooms:
Not specified by State Standards.
Ownership:
Owner-occupancy will not be required for new ADUs (conversion and new construction) built between 2020 and 2025. ~ SB13
Utility connections:
Local health officer approval where a private sewage disposal system is being used, if required. (State requirements)
Allowed Zones:
*** Beginning in 2020, according to state law, all residential zoning districts, including single-family and multi-family, are allowed to build Accessory Dwelling Units. ***
The City’s Accessory Dwelling Unit (ADU) Ordinance permits the development of an ADU on all lots occupied with a proposed or existing single-family dwelling unit and zoned for single-family or multi-family residential use. However, State law does not prohibit Homeowner’s Associations abilities to regulate ADUs and does not override Covenants, Conditions, and Restrictions (CC&Rs). Additionally, the ADU Ordinance does not supersede any recorded condo plan notes and definitions that may prevent or restrict development of an ADU.
Residential Building Code:
The California Building Code (CBC) 2019 is adopted.
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