20.00.10 Accessory Dwelling Unit (ADU) Regulations

A. Purpose. The purpose of this Section is to establish standards, in compliance with California Government Code Section 65852.2, for the development of accessory dwelling units.

B. Intent. The provisions of this Section are intended to implement the provisions of the General Plan Housing Element that encourage the development of housing types for all economic segments of the community and to minimize governmental constraints on residential development. Furthermore, these provisions are intended to increase the supply of smaller and affordable housing while ensuring such housing remains compatible with the existing neighborhood.

C. Applicability. Except as otherwise provided by this Chapter or County Code, accessory dwelling units shall be allowed by-right (ministerially permitted) in any zone which allows for residential uses. This includes mixed-use zoning districts which allow residential and nonresidential land uses.

D. General Requirements. An accessory dwelling unit:

1. Is a use that is accessory to an existing or proposed primary dwelling; 2. Shall be located on a parcel zoned to allow single-unit or multi-unit residential uses either by-right or with discretionary approval and that contains an existing or proposed primary dwelling; 3. Is not subject to the density requirements of the General Plan, but shall otherwise be consistent with the General Plan text and land use diagrams: 4. Shall not be sold or otherwise conveyed separately from the primary dwelling, except as otherwise provided in Government Code Section 65852.26; and 5. Shall not be rented for a term of less than 30 days. The primary dwelling may be rented for a term of less than 30 days.

E. Permit Requirements and Processing Procedures. An application for an accessory dwelling unit that complies with all applicable requirements of this Section and California Government Code Section 65852.2 shall be approved ministerially through the Building Permit process. A Building

Permit application for an accessory dwelling unit on a parcel with an existing or proposed single-unit or multi-unit dwelling shall be acted upon within 60 days of the Building Permit application being complete. The Building Permit applicant may request a delay in the County's processing of the Building Permit, which shall result in the tolling of the 60-day time period.

F. Planned Community District. Accessory dwelling units located in the P-C (Planned Community District) shall comply with the requirements of this Section.

G. Specific Plans. Accessory dwelling units located in areas governed by an adopted specific plan shall comply with the requirements of this Section.

H. Separate Access Required. An accessory dwelling unit shall have exterior access that is separate from the exterior access for the primary dwelling. A passageway that provides access to the accessory dwelling unit from a street is not required.

I. Fire Sprinklers. Fire sprinklers shall be required if required for the primary residence.

J. Accessory Dwelling Unit and Junior Accessory Dwelling Unit. Two accessory dwelling units, one as described in Government Code Section 65852.2(e)(1 )(A) and one as described in Government Code Section 65852.2(e)(1)(B), and one junior accessory dwelling unit, as described in Government Code Section 65852.2(e)(1)(A), are allowed per parcel with an existing or proposed single-unit dwelling, when in compliance with the requirements of this County Code.

K. Illegal Units. This Section shall not validate any existing illegal accessory dwelling unit. The standards and requirements for the conversion of an illegal accessory unit to a legal conforming unit shall be the same as for a new accessory dwelling unit.

L. Development Standards. A Building Permit for an accessory dwelling unit shall be issued only when the accessory dwelling unit complies with all the following development standards:

1. Number. Accessory dwelling units shall comply with the following: a. Two accessory dwelling units, one as described in Government Code Section 65852.2(e)(1)(A) and one as described in Government Code Section 65852.2(e)(1)(B), and one junior accessory dwelling unit, as described in Government Code Section 65852.2(e)(1)(A), on a parcel with an existing or proposed single-unit dwelling. b. No more than two detached accessory dwelling units on a parcel with an existing or proposed multi-unit dwelling. c. Within an existing multi-unit dwelling structure, multiple accessory dwelling units shall be allowed in areas that are not used as livable space, including but not limited to storage rooms, boiler rooms, passageways, attics, basements, or garages. The number of accessory dwelling units allowed is limited to a maximum of 25-percent of the number of multi-unit dwellings within the structure. In no case shall fewer than one accessory dwelling unit be allowed. 2. Location. An accessory dwelling unit shall be allowed in the following locations: a. Within an existing or proposed primary dwelling, including attached garages, storage areas, or similar attached areas; b. An existing or proposed detached accessory structure; or

c. Above a garage that is attached to or detached from the primary dwelling; d. When located within an existing accessory structure, the accessory structure shall comply with the following:

(1) Only be enlarged to provide ingress and egress and, in no case, shall the expansion exceed 150 square feet; (2) Provide exterior access; and (3) Provide side and rear setbacks for fire and safety in compliance with the California Building Code. 3. Setbacks. An accessory dwelling unit shall comply with the following setback requirements: a. Attached Unit. An attached accessory dwelling unit shall be subject to the same front setback requirement applicable to the primary dwelling, unless it precludes development of an accessory dwelling unit that is at least 800 square feet, at least 16 feet in height, with four-foot side and rear yard setbacks, and complies with all other development standards of this Section. In addition to the safety triangle standards established in Section 12.08.10, the interior side, street side, and rear setbacks shall be a minimum of four feet. No rear, street side, or interior side setback is required for an accessory dwelling unit that is located fully within an existing single-unit dwelling, provided a separate exterior access is provided for the accessory dwelling unit. b. Conversion of Existing Living Space or Existing Accessory Building. An accessory dwelling unit or portion of an accessory dwelling unit located within the existing space of an existing dwelling or within an existing detached accessory structure shall not require a setback from the rear, street side, or interior side property lines. c. Existing Detached Private Garage. No setback shall be required for an existing garage that is converted to an accessory dwelling unit, except as required for fire and safety. A setback of four feet from the interior side, street side, and rear property lines is required for an accessory dwelling unit constructed above an existing garage.

the rear, street side, or interior side property lines. c. Existing Detached Private Garage. No setback shall be required for an existing garage that is converted to an accessory dwelling unit, except as required for fire and safety. A setback of four feet from the interior side, street side, and rear property lines is required for an accessory dwelling unit constructed above an existing garage.

d. Replacement of Existing Structures. For an accessory dwelling unit constructed in the same location and to the same dimensions as an existing structure, setbacks of four feet from the interior side, street side, and rear property lines shall be provided. e. New Detached Unit. A new detached accessory dwelling unit shall comply with the front setback of the underlying zoning district, unless it precludes development of an accessory dwelling unit that is at least 800 square feet, at least 16 feet in height with four-foot side and rear yard setbacks and complies with all other development standards of this Section. A detached accessory dwelling unit shall be located a minimum of four feet from the interior side, street side, and rear property lines. 4. Distance Between Structures. A detached accessory dwelling shall maintain a minimum of five feet of separation between the primary dwelling and other accessory structures on the site or the minimum distance required by the Building Code, whichever is greater. 5. Maximum Floor Area. Accessory dwelling units shall comply with the following floor area standards: a. An accessory dwelling unit shall not exceed 1,200 square feet in floor area. b. The floor area of an ADU or JADU is measured from the exterior walls at the building envelope, excluding any garage area or unenclosed covered porch areas. For the purposes of measurement all attached and/or interior storage areas, mezzanines, lofts, attics (except those less than seven feet in height accessed by a crawlspace and/or other code compliant access), and similar uses shall be counted in the total square footage. 6. Height Limit. Accessory dwelling units are limited to a maximum height of 16 feet, except as established below: a. If a detached accessory dwelling is located within a half-mile of a major transit stop or high-quality transit corridor, as defined in Chapter 20.04 (Definitions), the unit is limited to a maximum height of 18 feet, and may be up to two feet taller, for a maximum of 20 feet, if necessary to match the roof pitch of the primary dwelling unit. b. If a detached accessory dwelling is located on a parcel with a multistory, multi unit

dwelling structure, the unit is limited to a maximum height of 18 feet. c. An accessory dwelling located above a detached garage is limited to a maximum height of 25 feet.

d. An accessory dwelling attached to the primary dwelling is limited to the height allowed in the underlying zoning district.

7. Lot Coverage. An accessory dwelling unit shall comply with the lot coverage requirements of the applicable zoning district, except that in the case where the allowable site coverage would preclude an accessory dwelling unit, one attached or detached accessory dwelling unit with a maximum size of 800 square feet, regardless of the number of bedrooms, shall be allowed and shall comply with the requirements of this Section. 8. Privacy. For an accessory dwelling unit located outside of the required setbacks for the primary dwelling and which faces an adjoining property, at least one of the following measures shall be used to provide privacy: a. All windows located outside of the required setback of the primary dwelling and which fronts an adjoining property shall be clerestory (minimum of five feet, six inches above the finished floor);

b. All windows located outside of the required setback of the primary dwelling and which fronts an adjoining property shall have permanently obscured glazing; or c. At least 18 inches of lattice that is 50 percent open shall be added to a solid six foot fence located on the shared property line. 9. Parking. One off-street, all-weather parking space is required for an accessory dwelling unit in addition to that required for the primary dwelling, except as established below. a. No offstreet parking shall be required if any of the following circumstances exist: (1) The accessory dwelling is located within one-half mile of public transit. (2) The accessory dwelling unit is located on a property which is recognized as historically significant. (3) The accessory dwelling unit is part of the existing primary residence or an existing accessory structure. (4) When onstreet parking permits are required but not offered to the occupant of the accessory dwelling unit. (5) Where there is a car share vehicle located within one block of the accessory dwelling unit. (6) When a permit application for an accessory dwelling unit is submitted with a permit application to create a new single-family dwelling or a new multifamily dwelling on the same lot, provided that the accessory dwelling unit or the parcel satisfies any other criteria listed in this paragraph. b. The required off-street parking space may be covered or uncovered and shall be allowed in tandem and in setback areas, unless the review authority makes specific findings that such parking is not feasible due to specific site topographical or fire and life safety conditions. c. If a garage, carport, or covered parking is demolished in conjunction with the construction of an accessory dwelling unit or converted to an accessory dwelling unit, replacement parking is not required.

• • (Ord. 2023 006 (part), 2023; Ord. 95 03 (part), 1995)