Existing law, the Planning and Zoning Law, among other things, provides for the creation by ordinance, or by ministerial approval if the local agency has not adopted an ordinance, of an accessory dwelling unit (ADU) or a junior accessory dwelling unit (JADU) in accordance with specified standards and conditions. Existing law defines the term "junior accessory dwelling unit" for these purposes to mean a unit that is no more than 500 square feet in size and contained entirely within a single-family structure.
This bill would revise the definition of a "junior accessory dwelling unit" to require the size of a JADU to be no more than 500 square feet of interior livable space.
Existing law makes certain declarations of the Legislature's intent regarding the effect of an ADU ordinance. Existing law authorizes the Department of Housing and Community Development to review, adopt, amend, or repeal guidelines to implement uniform standards or criteria that supplement or clarify the terms, references, and standards for an ADU.
This bill would revise the above-described declaration of legislative intent to additionally apply with respect to a JADU ordinance. The bill would also expand the department's authority to review, adopt, amend, or repeal guidelines to additionally grant that authority with respect to terms, references, and standards for JADUs.
Existing law requires a local agency to submit an ADU ordinance to the Department of Housing and Community Development within 60 days after the adoption for department review, as specified. Under existing law, the standards applicable to an ADU under these provisions supersede a conflicting local ordinance, except as specified.
This bill would similarly require a local agency to submit a JADU ordinance to the department within 60 days after adoption for department review. The bill would also specify that the standards applicable to a JADU supersede any conflicting local ordinance, except as specified.
Existing law requires a local agency to consider ministerally a permit application for an ADU or a JADU within 60 days, as specified. If a local agency has not adopted an ADU ordinance, existing law requires a permit application for an ADU to be considered ministerially within 60 days, as specified. Existing law requires a local agency to determine whether an application for a postentitlement phase permit is complete and provide a written notice of this determination to the applicant within 15 business days after receiving the application, as specified.
If a local agency has not adopted a JADU ordinance, this bill would additionally require that a permit application for a JADU to be considered ministerially in a manner similar to the above-described requirement for ADUs. For the purposes of these provisions, the bill would require an application for an ADU or a JADU to be deemed complete in the same form and manner as an application for a postentitlement permit.
Existing law imposes limits on construction, connection, and impact fees and capacity charges imposed on an ADU, including prohibiting impact fees upon the development of an ADU based on if the ADU is 750 square feet and requiring that any impact fee on an ADU of 750 square feet or more be charged proportionately in relation to the square footage of the primary dwelling unit. Existing law prohibits a local agency, special district, or water corporation from requiring the applicant to install a new or separate utility connection between an ADU and the utility or imposing a related connection fee or capacity charge for specified ADUs, except as specified.
This bill would revise these provisions to additionally apply to construction, connection, and impact fees and capacity charges imposed on a JADU. The bill would revise the above-described limitation on impact fees to, instead, prohibit impact fees upon the development of an ADU or JADU that has 750 square feet of interior livable space or less, and to require that any impact fee on an ADU or JADU that has more than 750 square feet of interior livable space be charged proportionately in relation to the square footage of the primary dwelling unit.
Existing law authorizes the governing board of a school district to levy a fee, charge, dedication, or other requirement against construction within the boundaries of the school district for the purpose of funding the construction or reconstruction of a school facility, subject to specified limitations. Under existing law, the fee, charge, dedication, or other requirement may only apply to specified constructions, including residential construction if the resulting assessable space exceeds 500 square feet.
This bill would specify that an ADU or a JADU that contains less than 500 square feet of interior livable space does not increase assessable space by 500 square feet under these provisions.
Existing law prohibits a local agency from establishing by ordinance a maximum square footage for an attached or detached ADU that is either less than 800 square feet or 1,000 square feet for an ADU that provides more than one bedroom. Existing law also prohibits a local agency from establishing by ordinance any requirement for a zoning clearance or separate zoning review or any other minimum or maximum size for an ADU, size based upon a percentage of the proposed or existing primary dwelling, or limits on lot coverage, floor area ratio, open space, front setbacks, and minimum lot size, for attached or detached dwellings that does not permit at least an 800-square foot ADU with four-foot side and rear yard setbacks.
This bill would revise these size limitations to be based on the square feet of interior living space of the ADU.
Existing law requires a local agency to ministerially approve a building permit application within a residential or mixed-use zone for specified ADUs or JADUs, including one detached, new construction, ADU that does not exceed 4-foot side and rear yard setbacks for a lot with a proposed or existing single-family dwelling. For these ADUs and JADUs, existing law authorizes a local agency to impose specified height limitations and total floor area limitations of no more than 800 square feet. Existing law prohibits a local agency from imposing a requirement that an ADU install a fire sprinkler if a sprinkler is not required for the primary residence.
This bill would require a local agency to ministerially approve a building permit application for a combination of the specified ADUs or JADUs and revise the total area limitation to be based on the square feet of interior livable space. The bill would revise the prohibition on requiring fire sprinkler installation, as described above, to additionally apply to a JADU.
This bill would make other technical and conforming changes to the provisions governing the review and approval of ADUs and JADUs.
By imposing additional duties on local planning officials, this bill would impose a state-mandated local program.
The California Constitution requires the state to reimburse local agencies and school districts for certain costs mandated by the state. Statutory provisions establish procedures for making that reimbursement.
This bill would provide that no reimbursement is required by this act for a specified reason.

Statutes affected:
SB 543: 65956 GOV
02/20/25 - Introduced: 65956 GOV
03/25/25 - Amended Senate: 65941.1 GOV, 65941.1 GOV, 66311 GOV, 66311 GOV, 66313 GOV, 66313 GOV, 66317 GOV, 66317 GOV, 66320 GOV, 66320 GOV, 66321 GOV, 66321 GOV, 66323 GOV, 66323 GOV, 66324 GOV, 66324 GOV, 66327 GOV, 66327 GOV, 66332 GOV, 66332 GOV, 66335 GOV, 66335 GOV, 65956 GOV
04/09/25 - Amended Senate: 65941.1 GOV, 66311 GOV, 66313 GOV, 66317 GOV, 66320 GOV, 66321 GOV, 66323 GOV, 66324 GOV, 66327 GOV, 66332 GOV, 66335 GOV