Chapter 21.28 — SINGLE-FAMILY RESIDENTIAL DISTRICT (R-1)

Note: Prior history: Prior Code § 9-114 and Ords. NS 988 and NS 1001.

The regulations set forth in this chapter shall apply in all R-1 districts and shall be subject to the provisions of Chapter 21.08 , unless otherwise specified in this chapter. (Ord. CS 106 §4, 1984; Ord. CS 1408, 12/9/2025)

Uses permitted in R-1 districts:

• A. One single-family dwelling on any one parcel;

• B. Accessory uses and buildings normally incidental to single-family residences. This is not to be construed as permitting any commercial use;

• C. One sign, not over six square feet in area, and pertaining to only the sale, lease or rental of the property upon which the sign is to be located;

• D. Home occupations, as regulated by Chapter 21.94 ;

• E. Crop farming;

• F. Where there is a recorded subdivision map, there may be maintained one advertising sign of not more than two hundred square feet in area illuminated but nonflashing and nonanimated, and one temporary sales office, for a period of two years immediately following the recording date of the subdivision map, however, the time for maintaining the sign and temporary sales office may be extended for an additional two-year period provided a use permit is first secured. The sign and office shall be subject to all yard requirements and located within the boundary of the subdivision;

• G. Racing homing pigeons as regulated in Chapter 21.92 ;

• H. Garage sales;

• I. A mobile home in lieu of any permitted single-family dwelling as regulated by Chapter 21.72 ;

• J. Family day care homes;

• K. Repealed;

• L. Duplexes on corner lots of subdivisions created after January 1, 1979; provided, that each unit fronts on a separate street and that, in the opinion of the planning director, each unit has the appearance of a single-family residence. Applicants may be required to submit building elevations or other proof that the duplex will meet this requirement;

• M. Accessory dwellings as regulated by Chapter 21.74 .

(Ord. CS 106 §4, 1984; Ord. CS 350 §1, 1989; Ord. CS 663 §§7, 18, 19, 1998; Ord. CS 1290 §15, 2021; Ord. CS 1408, 12/9/2025)

Uses permitted, subject to first securing a use permit in each case:

• A. Churches (excluding tent and open-air churches), schools offering general academic instruction equivalent to the standards prescribed by the State Board of Education, hospitals, public buildings, facilities for public utilities, and community antenna systems with an antenna not exceeding one hundred fifty feet in height;

• B. Repealed;

• C. Mobile home parks; provided that all units are connected to a public sanitary sewer and public water system and that the density does not exceed the maximum allowable in this district;

• D. Family day care homes for more than fourteen persons;

• (Ord. CS 106 §4, 1984; Ord. CS 1290 §16, 2021; Ord. CS 1408, 12/9/2025)

Height limit in R-1 districts:

• A. For dwellings, maximum thirty-five feet;

• B. For detached accessory buildings, maximum twenty feet;

• C. No fence, hedge, or screen planting shall be constructed or permitted to grow in excess of eight feet in height within any required side or rear yard, nor in excess of three feet within any required front yard, or side yard of a corner lot, except fences within the side and rear yard which enclose electrical substations which may be constructed to the height required by law or unless the director determines that visibility will not be obstructed.

• (Ord. CS 106 §4, 1984)

Minimum lot width requirements in R-1 districts, for the creation of new parcels, shall be as specified in Title 20, Subdivision Ordinance, of the County Code. (Ord. CS 1408, 12/9/2025)

Building site are required in R-1 districts:

• A. Sites serviced by public sewer and water facilities, five thousand square feet;

• B. Sites serviced by public water and septic tank facilities or private well and public sewer facilities, twenty thousand square feet;

• C. Sites serviced by private well and septic tank facilities, one acre;

• D. For parcels located wholly within the boundaries of an urbanized area or urban cluster, as designated by the United States Census Bureau, the minimum building site area shall be as specified in Section 21.28.090 of this chapter.

• (Ord. CS 106 §4, 1984; Ord. CS 663 §15, 1998; Ord. CS 1408, 12/9/2025)

Lot coverage permitted in R-1 districts:

For aggregate building coverage, maximum fifty percent of lot area, except as allowed in Section 21.28.090 of this chapter.

(Ord. CS 106 §4, 1984; Ord. CS 1408, 12/9/2025)

Yards required in R-1 districts:

• A. Front yard.

  1. Not less than seventy feet from the existing centerline of the street, nor less than fifteen feet from the planned street line on a major street or expressway, whichever is the greater. The vehicle opening of any building shall be no closer than twenty feet to the property line toward which the opening faces,

  2. Not less than forty-five feet from the existing centerline of the street on a collector street (sixty feet wide), nor less than fifteen feet from the planned street line where a specific plan has been adopted. The vehicle opening of any building shall be no closer than twenty feet to the property line toward which the opening faces,

  3. Not less than forty feet from the existing centerline of the street on a minor street (fifty feet wide) nor less than fifteen feet from the planned street line where a specific plan has been adopted. The vehicle opening of any building shall be no closer than twenty feet to the property line toward which the opening faces;

• B. Side Yard, Interior Lot Line and Rear Yard. Five feet;

• C. Side Yard, Corner Lots. The main building and garages or accessory buildings not having direct vehicular access to the street may be located five feet closer to the planned street line than at the front yard.

• (Ord. CS 106 §4, 1984; Ord. CS 663 §40, 1998)

See Chapter 21.76 for all off-street parking requirements. (Ord. CS 106 §4, 1984; Ord. CS 1408, 12/9/2025)

In accordance with the California Housing Opportunity and More Efficiency (HOME) Act, the following standards shall be applicable to parcels located wholly within the boundaries of an urbanized area or urban cluster, as designated by the United States Census Bureau:

• A. Parcel Splits. Parcels may be split provided the following standards are met:

  1. Building Site Area. The minimum building site area for parcels served with public sewer and water shall be one thousand two hundred square feet for the purpose of the creation of new parcels in accordance with the HOME Act. Building site area standards for parcels not served by water and sewer shall be subject to the building site area standards set forth in Chapter 21.28.050;

  2. A parcel may be split into no more than two parcels;

  3. Each resulting parcel shall be approximately equal in size and no smaller than forty percent of the original parcel being split;

  4. The original parcel being split shall not have been created as a result of the provisions of the HOME Act;

  5. The original parcel being split shall not be adjacent to a parcel previously split by the same property owner; and

  6. All resulting parcels shall have approved access as defined by Title 20, Subdivision Ordinance, of the County Code.

• B. Exceptions. The creation of a parcel under this section shall not be permitted if one of the following applies:

  1. The county building official makes a written finding, based upon a preponderance of the evidence, that the proposed housing development project would have a specific, adverse impact, as defined and determined in Section 65589.5(d)(2) of the California Government Code, upon public health and safety for which there is no feasible method to satisfactorily mitigate or avoid the specific, adverse impact;

  2. The parcel is located within a High- or Very-High Fire Hazard Severity zone; or

  3. The parcel is located within the Federal Emergency Management Act adopted floodway.

• C. Other Development Standards. Except where otherwise allowed by California Government Code Sections 65852.21 and 66411.7 , the provisions of County Code shall be applicable to any development on a parcel split in accordance with the HOME Act.

• (Ord. CS 1408, 12/9/2025)