Everything about building Accessory Dwelling Units in Orange, CA
Check your property's zoning, browse designs & get contractor estimates for your ADU project:
Number of ADUs allowed:
One ADU is permitted on a lot with a proposed or existing single-family dwelling.
Attached ADUs are allowed within the proposed or existing living area of a single-family dwelling, or within existing non-habitable space attached to a single-family dwelling, including attached garages.
New construction: One attached ADU is permitted per lot, where no detached ADU exists. An existing JADU may be converted to an attached ADU permitted by this subsection if no attached or detached ADU exists.
One JADU is permitted per lot.
Types of ADUs allowed:
ADUs are limited to properties zoned to allow single-family or multifamily dwellings when the property includes a proposed or existing primary residence in the form of a single-family or multifamily dwelling. Properties zoned to allow residential uses exclusively as an accessory use, or as a use that is not permanent long-term housing, shall not be eligible for an ADU or JADU unless the property is exclusively developed with a primary, legal-nonconforming, long-term, permanent residential use.
Lot size:
There shall be no minimum lot size in order to construct an ADU or JADU.
ADU size:
A. Any Size ADU Within Existing Building Area. No setback shall be required for an existing living area or accessory structure or a structure constructed in the same location and to the same dimensions as an existing structure that is converted to an ADU or to a portion of an ADU. Portions of the ADU constructed outside of the existing structure shall comply with the setbacks of the zoning district.
B. ADUs of eight hundred (800) square feet or less.
1. Setbacks of no more than four feet from the side and rear lot lines shall be required for an ADU that is not converted from an existing structure or a new structure constructed in the same location and to the same dimensions as an existing structure.
2. Front setbacks shall be pursuant to the setback for the zoning district.3.An Administrative Adjustment may not be granted to lessen required setbacks.
C. ADUs greater than eight hundred (800) square feet.1.Side and rear setbacks of no more than four feet shall be required for any ADU in excess of 800 square feet.2.Front setbacks shall be pursuant to the setback for the zoning district.
D. Fire and Safety Setbacks. Setbacks in all instances shall be sufficient for fire and safety, as determined by City fire and safety personnel
Setbacks:
A. Any Size ADU Within Existing Building Area. No setback shall be required for an existing living area or accessory structure or a structure constructed in the same location and to the same dimensions as an existing structure that is converted to an ADU or to a portion of an ADU. Portions of the ADU constructed outside of the existing structure shall comply with the setbacks of the zoning district.
B. ADUs of eight hundred (800) square feet or less.
1. Setbacks of no more than four feet from the side and rear lot lines shall be required for an ADU that is not converted from an existing structure or a new structure constructed in the same location and to the same dimensions as an existing structure.
2. Front setbacks shall be pursuant to the setback for the zoning district.3.An Administrative Adjustment may not be granted to lessen required setbacks.
C. ADUs greater than eight hundred (800) square feet.
1. Side and rear setbacks of no more than four feet shall be required for any ADU in excess of 800 square feet.
2. Front setbacks shall be pursuant to the setback for the zoning district.
D. Fire and Safety Setbacks. Setbacks in all instances shall be sufficient for fire and safety, as determined by City fire and safety personnel.
Parking:
A. No additional parking shall be required in association with the creation of a JADU. However, any required parking for the primary residence that is eliminated for the creation of a JADU shall be replaced on-site in conformance with all requirements of Chapter 17.14.
B. Except as specified in Section 17.29.130.D, an ADU requires one additional parking space per ADU or per bedroom, whichever is less.
1. Required parking spaces may be provided as tandem parking on a driveway only if the required parking space is not within the setback established for the zoning district.
2. Required parking spaces may also be provided in a tandem configuration within a carport or garage meeting the setback requirements of the zoning district.
3. Each parking space must maintain twenty (20) feet deep by ten feet wide interior clear dimensions.
4. In the event that required ADU parking is unable to be provided pursuant to subsections 1 or 2 above, and the parking area meeting the dimensions of subsection 3 can be accommodated on-site within required setbacks, an alternate parking location shall be determined by the Community Development Director.
C. When a garage, carport, or covered parking structure is demolished in conjunction with the construction of an ADU or converted to an ADU, those off street parking spaces are not required to be replaced. Only those portions of garage, carport, or covered parking structure necessary to accommodate the ADU are authorized for demolition. Any remaining area with interior dimensions of at least eighteen (18) feet long by nine feet wide shall remain as parking when required for the primary residence.
D. No parking is required for an ADU in any of the following instances:
1. The ADU is located within one-half mile walking distance of public transit as defined by the Department of Housing and Community Development.
2. The ADU is located within an architecturally and historically significant historic district.
3. The ADU is part of the proposed or existing primary residence or an accessory structure.
4. In the event on-street parking permits are required but not offered to the occupant of the ADU.5.When there is a permanently reserved parking space or parking facility specifically for a car share vehicle located within one block of the accessory dwelling unit.
Fire Safety:
The installation of fire sprinklers shall not be required in an ADU if sprinklers are not required for the primary residence. Construction of an ADU may impose fire sprinkler requirements for the primary residence and ADU.
Shape, materials and style:
For all new construction ADUs, roof forms and pitch shall match the principal residence. Any garage door(s) shall be removed from a garage or other accessory structure that is converted to an ADU or JADU, and the opening shall be treated and finished to match the building.
Exception. An ADU or JADU that complies with the requirements of Government Code Section 65852.2(e) shall not be subject to design and development standards unless otherwise provided herein.
Height:
ADUs and JADUs may not exceed the greater of sixteen (16) feet in height or the height of existing space being converted.
Design review:
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:
To ensure the accessory status of ADUs, to provide for reasonable livability, and to accommodate differing bedroom counts to fulfill diverse living needs in the community, the number of bedrooms in an ADU or JADU shall be proportionate to the square feet of living area for the ADU or JADU as follows:
A.ADUs or JADUs one hundred fifty (150) to five hundred (500) square feet shall be limited to one bedroom.
B.ADUs five hundred one (501) to one thousand (1,000) square feet shall be limited to two bedrooms.
C.ADUs created from repurposed accessory structures having more than one thousand (1,000) square feet may have one additional bedroom for each five hundred (500) square foot increment of living area.
Ownership:
A. An ADU may be rented separate from the primary residence, but may not be sold or otherwise conveyed separate from the primary residence.
B. Owner occupancy is not required for an ADU or primary residence until after January 1, 2025, at which time owner occupancy shall be required for new ADUs if the applicable provision of state law is not extended.
C. Owner-occupancy is required for a single-family dwelling with a JADU. The owner may reside in either the remaining portion of the single-family dwelling or in the JADU. Owner-occupancy shall not be required if the owner is another governmental agency, land trust, or housing organization.
D. ADU and JADU rentals shall be for a term longer than thirty (30) days and shall not be eligible as a short term rental.
Utility connections:
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
Historic Requirements:
The City may apply design standards on ADUs to prevent adverse impacts on any real property that is listed in the California Register of Historic Resources.
The City may impose standards including, but not limited to, design, development, and historic district design standards on ADUs. ADUs in a historic district shall adhere to the Historic Preservation Design Standards for that district.
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. ***
Open Space:
Open space requirements of Sections 17.14.110 and 17.19.090 are not applicable for the construction of an ADU up to eight hundred (800) square feet but shall apply for an ADU greater than eight hundred (800) square feet.
Residential Building Code:
The California Building Code (CBC) 2019 is adopted.
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