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Property layout with ADU locations smInterpreting all the moving parts within a city can be overwhelming, confusing, and frustrating for many homeowners.

We work with you to set expectations early-on to determine what’s possible for your property and budget and handle the design, plans, and permits.

What You Need to Know About Building an ADU in Your City

  1. Three Per Lot: There’s a limit to three ADU’s (one junior and one detached) per residential lot zoned for single-family residences with a single-family residence already built on the lot (triplex).

  2. Separate Entrance: An ADU must have its own separate entrance.

  3. Kitchen: An ADU must have an efficiency kitchen which includes a sink, cooking appliance, counter surface, and storage cabinets.

  4. Bathroom: An ADU must include the minimum of a 3/4 bath.

  5. Fire Sprinklers: ADUs are to be considered part of the single-family residence for the purposes of fire and life protection ordinances and regulations, such as sprinklers and smoke alarms. ADUs shall not be required to provide fire sprinklers if they were not a requirement for the primary residence.

  6. approved stampCity Approval and Hearings: Cities are required to approve an ADU within 60 days, without a hearing or discretionary review.

  7. Homeowner Occupancy: Cities cannot require owner occupancy until 2025.

  8. Minimum Size: An ADU must have a minimum living area of 150 square feet.

  9. ADU Size Single Family: A city is required to approve any attached or detached ADU under 1200 square feet unless the city adopts a new ADU ordinance setting local government standards for a single-family zoned lot. If a city adopts such an ordinance it must follow two restrictions: One, no maximum unit size limit under 850 square feet (or 1000 square feet for a two-bedroom ADU). Two, a floor area ratio must allow development of at least one 800 square feet attached or detached ADU on every lot.

  10. Conversion Size: A conversion ADU may be up to 1200 SF regardless of the size of the parcel or home.

  11. Conversion Additional Square Footage: A Conversion ADU may be expanded up to 150 square feet, not to exceed 1200 square feet total, except as may be necessary to accommodate ingress and egress to the ADU.

  12. Conversion of a Structure: A conversion ADU can be created from a legal structure built at any time (i.e. garage, accessory structure, storage room) and has setbacks sufficient for fire safety based on local ordinance.

  13. Junior ADU Limits: JADUs are limited to no more than 500 square feet in size and must be: Attached to a single family home, exterior entrance is separate from the primary residence, include a kitchenette with counter space, cabinets, and appliances and interior access to a bathroom.

  14. Junior ADU Connections to Primary Residence: Allowing interior connection between ADU and primary unit is allowed, i.e. laundry room.

  15. New Home and ADU Construction: An ADU can be developed at the same time as a primary unit, under most of the same rules.

  16. Single Story Height Limit and Property Line Set Backs: The height limit for a single story ADU is 16 feet with a side and rear set back of 4 feet.

  17. Second Story Height Limit and Set Backs: The height limit and set back requirements for a two story ADU is dependent on local ordinance.

  18. Lot Requirements and Coverage: There are no minimum lot size requirements.

  19. Development and Impact Fees: ADUs that are 750 square feet and smaller are not subject to impact fees (schools, parks, water). Fees for ADUs over 750 square feet are limited and determined based on the primary dwelling square footage.

  20. Homeowners Associations: An HOA must allow the construction of ADUs.

  21. Utility Fee Requirements for Conversions: Where ADUs are being created within an existing structure (primary or accessory), new or separate utility connections and fees (connection and capacity) are not required.

  22. Parking: There are no parking requirements for an ADU created through the conversion of existing space or located within a half-mile walking distance of a bus stop or transit station.

  23. Multi-Family and Mixed-use Zoned Properties: Up to 2 new construction ADUs (either attached or detached) is permitted, and up to the number that equals 25% of the existing dwelling units may be added by converting non-livable space within existing multi-family buildings with a 4-foot set and rear setback and 16-foor maximum height

  24. Persons with Disabilities: Local governments must provide exception to zoning and land use regulations which includes an ADU ordinance for people with disabilities. Potential exceptions are not limited and may include development standards such as setbacks and parking requirements and permitted uses that further the housing opportunities of individuals with disabilities.

  25. Sale of an ADU: An ADU cannot be sold separately from the primary residence.

  26. Short Term Rentals: An ADU and JADU can only be rented for terms longer than 30 days. Vacation rentals are not permitted.

Disclaimer: This list of rules and guidelines are a summary of the key provisions as a result laws Senate Bill 13, Assembly Bill 68, Assembly Bill 670, Assembly Bill 881, and previous ADU legislation.

Many cities have found loopholes around these laws and/or have adopted a local ordinance that exceeds the minimum requirements.

We Help Determine What Makes the Most Sense for You and Your Property


Understanding Accessory Dwelling Units and Their Importance in California

ca mapThe California legislature found and declared that allowing accessory dwelling units (ADUs) in single family and multifamily zones provides additional rental housing and are an essential component in addressing housing needs in California. In 2017 and 2019, changes to ADU laws further reduced barriers, better streamline approval and expand capacity to accommodate the development of ADUs.

ADUs are a unique opportunity to address a variety of housing needs and provide affordable housing options for family members, friends, students, the elderly, in-home health care providers, the disabled, and others. Further, Accessory Dwelling Units offer an opportunity to maximize and integrate housing choices within existing neighborhoods.

ADUs, in-law suites, and garage conversions offer benefits that address common development barriers such as affordability and environmental quality. ADUs are an affordable type of home to construct in California because they do not require paying for land, major new infrastructure, structured parking, or elevators. ADUs are built with cost-effective one- or two-story prefab, modular, or wood frame construction. ADUs work very well for couples, small families, friends, young people, and seniors.

ADUs also help California meet its diverse housing needs. Young professionals and students desire to live in areas close to jobs, amenities, and schools. To address the needs of individuals or small families seeking living quarters in high opportunity areas, homeowners can construct an accessory dwelling unit, convert a garage or underutilized part of their home. This flexibility benefits not just the people living in the space, but the homeowner as well, in the form of extra monthly rent income or the ability to keep family close.

Relaxed regulations and the cost to build an ADU make it a very feasible to create affordable housing option for students, elderly parents, young professionals and seniors looking to downsize. The cost of an ADU typically ranges between $70k to $200k including design, permits, and construction. The price point may sound expensive upfront but an ADU is a long-term investment. Once you factor in savings on childcare, senior housing, renting an office, rental income, and increased property value it is easy to determine the return on your investment.

Accessory Dwelling Units are a powerful type of housing because they allow for different uses, and serve different populations ranging from students and young professionals to young families, people with disabilities and senior citizens.

We Navigate the Process of Building an ADU in Your City

Cities that we currently work with in Southern California: Long Beach, Santa Ana, Seal Beach, Signal Hill, San Pedro, Rolling Hills Estates, Rancho Palos Verdes, Lomita, Torrance, Redondo Beach, Hawthorne, Compton, Lakewood, Norwalk, Cerritos, Los Alamitos, Cypress, Buena Park, Downey, Whittier, Los Angeles, Culver City, Santa Monica, Manhattan Beach, El Segundo, Montebello, Hacienda Heights, Fullerton, Anaheim, Garden Grove, Westminster, Fountain Valley, Yorba Linda, Placentia, Villa Park, Tustin, Orange, Irvine, Lake Forest, Laguna Beach, Huntington Beach, Costa Mesa, Newport Beach, Laguna Niguel, San Juan Capistrano, Mission Viejo, San Clemente, Rancho Santa Margarita, Alhambra, Arcadia, Pasadena, Glendale, Burbank, Encino, Calabasas.


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