ADU Accessory Dwelling Units & Home Renovations.
Contact us for questions or quotes.
Costa Mesa is a city in Orange County, California. It is known for its large selection of art galleries, performance venues, and museums. The city is home to the Orange County Fairgrounds, which hosts a number of events throughout the year, including the Orange County Fair. The city also features numerous retail centers, including the South Coast Plaza, a high-end shopping mall.
Regional Project Manager
Get New Construction, ADU, New Room Addition, Home Remodeling, Interior Design, Architecture Design, Single Family ADU, Multi Family ADU, Junior ADU & Garage Conversions in this city.
Accessory Dwelling Unit City Requirement
ADU Maximum Size
JADU Maxium Size
150 Feet addition or
max 50% Primary Dwelling Size
4 Feet Front & Side
18 Feet Detached 25 Feet Attached
No Parking Requirement or one space max
1/2 Mile from Public Transportation
Costa Mesa, CA, USA
Types of ADU
There are two types of ADUs - an ADU and a JADU. All residential lots can have one ADU and one JADU.
There are three kinds of ADU construction:
Detached: The unit is separated from the primary structure
Attached: The unit is attached to the primary structure
Converted Existing Space: Space (e.g., master bedroom, attached garage, storage area, or similar use, or an accessory structure) on the lot of the primary residence that is converted into an independent living unit
Junior Accessory Dwelling Unit (JADU): A specific type of conversion of existing space that is contained entirely within an existing or proposed single-family residence
Accessory Dwelling Units (ADUs) are a type of housing that allows for additional living space to be built on residential lots. There are two main types of ADUs: a traditional ADU and a Junior ADU (JADU).
A traditional ADU can be constructed in three ways: detached, attached, or by converting existing space on the property. A detached ADU is a standalone unit that is not physically connected to the primary residence, and typically built in the backyard or as a separate unit on the property. An attached ADU is physically connected to the primary residence and can be built as an addition to the primary structure or as an interior conversion, such as converting a basement or garage. A converted ADU utilizes existing space, such as a garage or storage area, on the property to create an independent living unit.
A Junior ADU (JADU) is a specific type of conversion of existing space that is contained entirely within an existing or proposed single-family residence. It is also known as a "in-law unit" or "granny flat." Unlike traditional ADUs, JADUs do not require a separate bathroom and typically smaller in size. The main purpose is to provide an affordable and more compact housing option for family members, friends, or renters.
Residential lots are allowed to have one traditional ADU and one JADU. Both types of ADUs offer flexible living options and help to address the need for additional housing, whether it's for aging family members, renters, or others.
All ADUs must comply with relevant state and local laws and regulations, including zoning laws, building codes, and parking requirements.
Single-Family ADU Accessory Dwelling Unit Development Standards
ADUs are permitted in single-family residential zoned properties (R-1). All ADUs shall be constructed with independent access separate from the main residence entrance. All ADUs shall have a living/sleeping area, a kitchen or kitchenette (i.e., stove or hotplate, refrigerator, and sink), and a bathroom that includes a shower or bathtub. ADUs are no longer subject to Lot Coverage and Floor Area Ratios of the city's zoning designation. The following are single-family ADU development standards:
Detached Accessory Dwelling Unit
Maximum of two stories or 25 feet
ADU shall match the architectural design of the existing or proposed main dwelling.
Attached Accessory Dwelling Unit
Maximum of two stories or 25 feet
Cannot exceed 50% of the existing main dwelling unit
ADU shall match the architectural design of the existing or proposed main dwelling
Setbacks for your ADU
ADUs shall adhere to the state's setbacks of four feet from the side and rear yard and must remain 6 feet from the existing main dwelling. Existing accessory structures and single-family homes that are converted into ADUs are exempt from meeting the required setbacks however, any expansion shall meet the four-foot side and rear yard setback, as pursuant to Government Code Section 65852.2.
Parking for Tenant
All new ADUs will be required to provide one additional parking space, cover, or uncovered if the proposed ADU is not within a one-half (.5) mile radius of public transit station (bus stops included). However, for accessory structures or a portion of the existing residence that is converted into an ADU, no additional parking is required. An ADU cannot have direct access to a garage if the proposed or existing garage has less than three spaces.
Junior ADU Development Standards
Junior Accessory Dwelling Units (JADUs) are very small living units created within the existing main dwelling. The JADU must have a living/sleeping area, and a kitchen or kitchenette (i.e., stove or hotplate, refrigerator, and sink). A bathroom is not required, however, if a bathroom is not provided, the JADU shall have direct access into the existing main dwelling unit. A JADU cannot exceed a total of 500 square feet and any expansion of the existing main dwelling to accommodate the JADU shall not exceed 150 square feet.
JADUs shall adhere to the state's setbacks of four feet from the side and rear yard. Existing single-family homes that are converted into JADUs are exempt from meeting the required setbacks as pursuant to Government Code Section 65852.2.
Parking is not required for JADUs, however, an ADU cannot have direct access to a garage if the proposed or existing garage has less than three spaces.
Multi-Family Lots ADU Development Standards
ADUs are permitted on multi-family zoned properties (R-2 and R-3). All ADUs shall be constructed with independent access separate from the main residence entrance. All ADUs shall have a living/sleeping area, a kitchen or kitchenette (i.e., stove or hotplate, refrigerator, and sink), and a bathroom that includes a shower or bathtub. ADUs are no longer subject to Lot Coverage and Floor Area Ratios of the city's zoning designation.
As you look to begin your whole home remodel, here's the general order of operations:
Planning and Design: This is the initial phase where architects, designers, and engineers develop plans for the ADU. This includes determining the size, layout, and features of the ADU, as well as ensuring that the ADU complies with all local zoning and building codes.
Demolition: If the ADU is being added to an existing structure, this phase involves removing any necessary parts of the original structure to make way for the new addition.
Rebuilding/Framing: This phase involves constructing the foundation and framing for the ADU. The foundation provides support for the ADU, while the framing forms the structure of the walls, floor, and roof.
Mechanicals/Plumbing/HVAC/Electrical: This phase involves installing the mechanical systems and electrical wiring necessary for the ADU to function. This includes items such as heating and cooling systems, plumbing, and electrical wiring.
Walls: This phase involves installing the walls of the ADU. This includes drywall, insulation, and any other necessary finishes to the interior walls.
Flooring: This phase involves installing the flooring of the ADU. This can include materials such as tile, hardwood, or carpet.
Cabinets: This phase involves installing cabinets, countertops, and other kitchen and bathroom fixtures.
Appliances: This phase involves installing appliances such as ovens, ranges, dishwashers, and refrigerators.
Note that some of the phases may happen simultaneously and/or there can be slight variations to the list provided depending on the specifics of the project and local codes.
Contact Us for more information.