Sep 8, 2026
City of Cotati
201 W. Sierra Avenue
Cotati, CA 94931
By Email: [email protected]; [email protected]; [email protected]; [email protected]; [email protected];
CC: [email protected]; [email protected]; [email protected]; Re: Proposed amendment to the City’s Accessory Dwelling Unit Ordinance Dear City of Cotati,
The California Housing Defense Fund (CalHDF) submits this letter as a public comment concerning item 7B for the Council meeting of Sep. 8, 2026, a proposed amendment to the City’s code sections governing the development of accessory dwelling units (ADUs) and junior accessory dwelling units (JADUs).
We appreciate that the City is updating its ordinance to keep pace with changes in state law.
However, the proposed ordinance does not comply with state ADU law for the reasons discussed in this letter. The City must amend the proposed ordinance in order to address these issues.
Background
The law gives local governments authority to enact zoning ordinances that implement a variety of development standards on ADUs. (Gov. Code, § 66314.) The standards in these local ordinances are limited by state law so as not to overly restrict ADU development. (See id.) Separately from local ADU ordinances, Government Code section 66323 establishes a narrower set of ADU types that local governments have a ministerial duty to approve. “Notwithstanding Sections 66314 to 66322 ... a local agency shall ministerially approve” these types of ADUs. (Id. at subd. (a).) This means that ADUs that satisfy the minimal requirements of section 66323 must be approved regardless of any contrary provisions of the local ADU ordinance. (Ibid.) Local governments may not impose their own standards on such ADUs. (Gov. Code, § 66323, subd. (b) [“A local agency shall not impose any objective development or design standard that is not authorized by this section upon any accessory dwelling unit that meets the requirements of any of paragraphs (1) to (4), inclusive, of subdivision (a).”].) 2201 Broadway, PH1, Oakland, CA 94612
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In addition, ADUs that qualify for the protections of Government Code section 66323, like other ADUs, must be processed by local governments within 60 days of a complete permit application submittal. (Gov. Code, § 66317, subd. (a).) State law also prohibits creating regulations on ADU development not explicitly allowed by state law. Government Code Section 66315 states, “No additional standards, other than those provided in Section 66314, shall be used or imposed, including an owner-occupant requirement, except that a local agency may require that the property may be used for rentals of terms 30 days or longer.”
Impermissible Size Limit for Section 66323 ADUs
Code section 17.42.170(B)(3)(a) limits all ADUs on single-family lots and attached ADUs on multifamily lots to 850 square feet for studio or one-bedroom ADUs and 1,000 square feet for 2+ bedroom ADUs.
Code section 17.42.170(B)(3)(c) limits detached ADUs on single-family lots and attached ADUs on multifamily parcels to 1,200 square feet, even though this conflicts with the more restrictive size limit in Code section 17.42.170(B)(3)(a).
Code section 17.42.170(B)(3)(d) further limits ADUs to 50% of the existing primary dwelling or 800 square feet.
However, these limits on ADU size violate the provisions of Government Code section 66323, subdivisions (a)(1), (a)(3), and (a)(4).
● Government Code section 66323, subdivision (a)(1) allows the conversion of existing space within a single family dwelling or accessory structure into ADUs without size restriction.
● Government Code section 66323, subdivision (a)(3) allows the conversion of non-livable space in multifamily buildings into ADUs without size restriction.
The City cannot impose a size restriction on these types of ADUs because Government Code section 66323, subdivision (b) prohibits the application of any local standards to section 66323 ADUs. Size restrictions are such a prohibited local standard.
From page 19 of the March 2026 HCD ADU Handbook (emphasis added):
A local agency may notimpose development or design standards, including both local standards and standards found in State ADU Law, on 66323 Units that are not 2 of 5
specifically listed in Government Code section 66323. (Gov. Code, § 66323, subds. (a), (b).) This includes, but is not limited to, parking, height, setbacks, or other zoning provisions (e.g., lot size, open space, floor area ratio, etc.).
Such size limitations are indeed other local zoning provisions that cannot be imposed on 66323 ADUs.
The City must amend its ADU ordinance to remove these size limits on section 66323 ADUs.
Impermissible Front Setbacks
Code section 17.42.170(B)(5)(a) imposes underlying front setback on all ADUs including 66323 ADUs. Code section 17.42.170(B)(3)(f) prohibits the development of an ADU greater than 800 square feet in the front setback.
However, the City may not impose any such front setbacks on ADUs eligible for the protections of Government Code section 66323. The City may not impose front setbacks limits on these ADUs due to the provisions of Government Code section 66323, subdivision (b): “A local agency shall not impose any objective development or design standard that is not authorized by this section upon any accessory dwelling unit that meets the requirements of any of paragraphs (1) to (4), inclusive, of subdivision (a).” This means that the City cannot impose any standards on section 66323 ADUs beyond what is specifically allowed in that section of state law, including front setbacks for ADUs developed pursuant to Government Code section 66323.
Furthermore, the City cannot force an applicant to place an ADU in the back yard when there is available space in the front setback. This is because Government Code section 66323, subdivision (b) forbids all local standards not authorized by that section.
See pages 16-19 of the March 2026 HCD ADU Handbook for more information on section 66323 ADUs. From page 16: “ … 66323 Units do not have to comply with lot coverage,front setbacks, and design standards”
The City must amend its ADU ordinance to remove this front setback requirement for section 66323 ADUs.
Impermissible Parking Requirements
Code section 17.42.170(B)(2) imposes parking requirements on all ADUs, “except when an exemption is provided by state ADU law.”
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However, the City cannot impose local development standards on ADUs that conform to the requirements of Government Code section 66323, subdivision (a), as section 66323, subdivision (b) specifically exempts such ADUs from all local requirements. This means that the City cannot impose parking requirements on section 66323 ADUs.
From page 19 of the March 2026 HCD ADU Handbook (emphasis added):
A local agency may not impose development or design standards, including both local standards and standards found in State ADU Law, on 66323 Units that are not specifically listed in Government Code section 66323. (Gov. Code, § 66323, subds. (a), (b).) This includes, but is not limited to, parking, height, setbacks, or other zoning provisions (e.g., lot size, open space, floor area ratio, etc.).
From page 33 of the HCD ADU Handbook:
In addition, local agencies may not impose parking requirements on 66323 Units.
Additionally, the caveat “except when an exemption is provided by state ADU law” is insufficient. The average homeowner will simply obey the provisions of the local code when applying for an ADU permit. The City must amend the ADU code to comply with state law, and not rely on this savings clause. (See Latinos Unidos Del Valle De Napa Y Solano v. County of Napa (2013) 217 Cal.App.4th 1160, 1169 [invalidating local ordinance and finding savings clause, which stated that state law would prevail over conflicting local law, was insufficient].) The City must exempt section 66323 ADUs from parking requirements, as is required by state law.
Impermissible Discretionary Process
Code section 17.42.170(B)(3)(b) requires discretionary approval of ADUs exceeding certain sizes. However, state law does not allow any such process.
Government Code section 66316:
“An existing accessory dwelling unit ordinance governing the creation of an accessory dwelling unit by a local agency or an accessory dwelling ordinance adopted by a local agency shall provide an approval process that includes only ministerial provisions for the approval of accessory dwelling units and shall not include any discretionary processes ...”
Government code section 66317, subdivision (a):
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“ A permit application for an accessory dwelling unit or a junior accessory dwelling unit shall be considered and approved ministerially without discretionary review or a hearing ...”
Because the City’s code illegally limits the size of 66323 ADUs (see above description of this issue), its discretionary pathway is illegally forcing applicants to seek discretionary review just to secure approval of an ADU that is already guaranteed by state law.
The City must eliminate this discretionary review and allow development of ADUs pursuant to Government Code section 66323 without any such discretionary process. ◄ ►
We applaud the City for updating its ADU as state law changes. However, the City must amend its ADU ordinance to address the above issues.
CalHDF is a 501(c)3 non-profit corporation whose mission includes advocating for increased access to housing for Californians at all income levels, including low-income households.
You may learn more about CalHDF at www.calhdf.org.
Sincerely,
Dylan Casey
CalHDF Executive Director
James M. Lloyd
CalHDF Director of Planning and Investigations
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