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ADU Questions and Answers

Updated: Feb 15, 2023

In September 2020, a new California Department Of Housing handbook regarding laws, rules, and regulations of newly built ADU’s was released. This article regards the laws of only the state of California, other states may be different.

1. What Is An ADU?

An ADU is an accessory dwelling unit with complete independent living facilities for one or more persons and has a few variations such as detached, where the unit is separated from the primary structure, attached, where the unit is attached to the primary structure. Also 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. As well as 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.

2. How Will an ADU Help Me Financially?

Not only do ADU’s increase the value of your current home from $150,000 and up, they are an asset that will only rise in value over time. ADU’s also create a way to collect monthly rent in which you can put toward your current home mortgage (if applicable.)

3. Can Setbacks Be Required For ADUs?

According to the California Department of Housing ADU Handbook, yes. The housing authority can impose development standards, such as setbacks, for the creation of ADUs. Setbacks may include front, corner, street, and alley setbacks. Additional setback requirements may be required in the coastal zone if required by a local coastal program. Setbacks may also account for utility easements or recorded setbacks.

4. Does The Housing Authority encourage the development of ADUs?

Yes. Pursuant to Government Code Section 65852.150, the California Legislature found and declared that, among other things, California is facing a severe housing crisis and ADUs are a valuable form of housing that meets the needs of family members, students, the elderly, in-home health care providers, people with disabilities and others. Therefore, ADUs are an essential component of California’s housing supply.

5. Are ADUs allowed jurisdiction wide?

No. ADUs proposed pursuant to subdivision (e) must be considered in any residential or mixed-use zone. For other ADUs, local governments may, by ordinance, designate areas in zones where residential uses are permitted that will also permit ADUs. However, any limits on where ADUs are permitted may only be based on the adequacy of water and sewer service, and the impacts on traffic flow and public safety. Further, local governments may not preclude the creation of ADUs altogether, and any limitation should be accompanied by detailed findings of fact explaining why ADU limitations are required and consistent with these factors.

6. Can ADUs exceed the general plan and zoning densities?

Yes. An ADU is an accessory use for the purposes of calculating allowable density under the general plan and zoning that does not count toward the allowable density. For example, if a zoning district allows one unit per 7,500 square feet, then an ADU would not be counted as an additional unit. Further, local governments could elect to allow more than one ADU on a lot, and ADUs are automatically a residential use deemed consistent with the general plan and zoning.

7. Are ADUs permitted ministerially?

Yes. ADUs must be considered, approved, and permitted ministerially, without discretionary action. Development and other decision-making standards must be sufficiently objective to allow for ministerial review. Examples include numeric and fixed standards such as heights or setbacks or design standards such as colors or materials. Subjective standards require judgement and can be interpreted in multiple ways such as privacy, compatibility with neighboring properties or promoting harmony and balance in the community; subjective standards shall not be imposed for ADU development. Further, ADUs must not be subject to a hearing or any ordinance regulating the issuance of variances or special use permits and must be considered ministerially.

8. Can I create an ADU if I have multiple detached dwellings on a lot?

Yes. A lot where there are currently multiple detached single-family dwellings is eligible for creation of one ADU per lot by converting space within the proposed or existing space of a single-family dwelling or existing structure and a new construction detached ADU subject to certain development standards.

9. Can I build an ADU in a historic district, or if the primary residence is subject to historic preservation?

Yes. ADUs are allowed within a historic district, and on lots where the primary residence is subject to historic preservation. State ADU law allows for a local agency to impose standards that prevent adverse impacts on any real property that is listed in the California Register of Historic Resources.

10. Can minimum and maximum unit sizes be established for ADUs?

Yes. A local government may, by ordinance, establish minimum and maximum unit size requirements for both attached and detached ADUs. However, maximum unit size requirements must be at least 850 square feet and 1,000 square feet for ADUs with more than one bedroom. For local agencies without an ordinance, maximum unit sizes are 1,200 square feet for a new detached ADU and up to 50 percent of the floor area of the existing primary dwelling for an attached ADU (at least 800 square feet). Finally, the local agency must not establish by ordinance a minimum square footage requirement that prohibits an efficiency unit, as defined in Health and Safety Code § 17958.1.

11. Can maximum unit sizes exceed 1,200 square feet for ADUs?

Yes. Maximum unit sizes, by ordinance, can exceed 1,200 square feet for ADUs. ADU law does not limit the authority of local agencies to adopt less restrictive requirements for the creation of ADUs. Larger unit sizes can be appropriate in a rural context or jurisdictions with larger lot sizes and is an important approach to creating a full spectrum of ADU housing choices.

12. Can parking requirements exceed one space per unit or bedroom for an ADU?

No. Parking requirements for ADUs shall not exceed one parking space per unit or bedroom, whichever is less. These spaces may be provided as tandem parking on a driveway. Guest parking spaces shall not be required for ADUs under any circumstances.

13. What is Tandem Parking for an ADU?

Tandem parking means two or more automobiles that are parked on a driveway or in any other location on a lot, lined up behind one another. Local agencies may choose to eliminate or reduce parking requirements for ADUs such as requiring zero or half a parking space per each ADU.

14. Is flexibility for citing parking required for an ADU?

Yes. Local agencies should consider flexibility when citing parking for ADUs. Off Street parking spaces for the ADU shall be permitted in setback areas in locations determined by the local agency or through tandem parking, unless specific findings are made. Specific findings must be based on specific site or regional topographical or fire and life safety conditions.

15. Can school districts charge impact fees for your ADU?

Yes. School districts are authorized but do not have to levy impact fees for ADUs greater than 500 square feet pursuant to Section 17620 of the Education Code. ADUs less than 500 square feet are not subject to school impact fees. Local agencies are encouraged to coordinate with school districts to carefully weigh the importance of promoting ADUs, ensuring appropriate nexus studies and appropriate fees to facilitate construction or reconstruction of adequate school facilities.

16. What types of fees are considered impact fees for an ADU?

Impact fees charged for the construction of ADUs must be determined in accordance with the Mitigation Fee Act and generally include any monetary exaction that is charged by a local agency in connection with the approval of an ADU, including impact fees, for the purpose of defraying all or a portion of the cost of public facilities relating to the ADU. A local agency, special district or water corporation shall not consider ADUs as a new residential use for the purposes of calculating connection fees or capacity charges for utilities, including water and sewer services. However, these provisions do not apply to ADUs that are constructed concurrently with a new single-family home.

17. Can I still be charged water and sewer connection fees for my ADU?

ADUs converted from existing space and JADUs shall not be considered by a local agency, special district or water corporation to be a new residential use for purposes of calculating connection fees or capacity charges for utilities, unless constructed with a new single-family dwelling. The connection fee or capacity charge shall be proportionate to the burden of the proposed ADU, based on its square footage or plumbing fixtures as compared to the primary dwelling. State ADU law does not cover monthly charge fees.

18. Can impact fees be charged for an ADU less than 750 square feet?

No. An ADU is exempt from incurring impact fees from local agencies, special districts, and water corporations if less than 750 square feet. Should an ADU be 750 square feet or larger, impact fees shall be charged proportionately in relation to the square footage of the ADU to the square footage of the primary dwelling unit.

19. Is a local government required to send an ADU Ordinance to the California Department of Housing and Community Development (HCD)?

Yes. A local government, upon adoption of an ADU ordinance, must submit a copy of the adopted ordinance to the California Department of Housing and Community Development (HCD) within 60 days after adoption. After the adoption of an ordinance, the Department may review and submit written findings to the local agency as to whether the ordinance complies with this section. (Gov. Code, § 65852.2, subd. (h)(1))

20. Are solar panels required for new construction ADUs?

Yes, newly constructed ADUs are subject to the Energy Code requirement to provide solar panels if the unit(s) is a newly constructed, non-manufactured, detached ADU. Per the California Energy Commission (CEC), the panels can be installed on the ADU or on the primary dwelling unit. ADUs that are constructed within existing space, or as an addition to existing homes, including detached additions where an existing detached building is converted from non-residential to residential space, are not subject to the Energy Code requirement to provide solar panels.

Neo Builders Inc. is an experienced construction company with a specialty in building ADU’s. Building an ADU with Neo Builders will increase your monthly cash flow in a stress free and organized process. Check out our Los Angeles rules and regulation page for more details.

Don’t wait, make the call today for a step towards financial freedom. An initial consultation and quote are FREE of charge.

For All Your ADU Needs

NEO Builders Inc.

3940 Laurel Canyon, Studio City #394, 91604

License #: 1061134



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