Single-family residence districts, hereinafter designated as R-1 districts, are established to provide for and protect established neighborhoods of one-family dwellings, and to provide space in suitable locations for additional development of this kind, together with appropriate community facilities and allowance for restricted interim cultivation of the soil compatible with such low-density residential development.

(Prior gen. code § 8-26.0)

Residential development within the R-1 districts located within the planning areas of San Lorenzo, Ashland, Cherryland, Fairview, or Castro Valley (areas within the Castro Valley Urbanized Area) shall be subject to the "Residential Design Standards and Guidelines for the Unincorporated Communities of West Alameda County," as amended. On matters not provided for in the Residential Design Standards and Guidelines for the Unincorporated Communities of West Alameda County, the respective regulations in this zoning ordinance shall apply.

(Ord. No. 2014-39, § 1, 10-7-14, eff. 1-1-15)

Every parcel designated on the zoning map as being in the R-E district, as well as every parcel designated as being in a R-1 district, shall be subject to these regulations for a single-family residence district, and shall be designated R-1 upon any revised zoning map.

(Prior gen. code § 8-26.1)

The following principal uses are permitted in an R-1 district:

A.

One one-family dwelling;

B.

Field crop, orchard, garden.

C.

In Castro Valley (areas within the Castro Valley Urbanized Area), Small family day cares and large family day cares.

(Prior gen. code § 8-26.2)

(Ord. No. 2012-58, § 8, 4-10-12; Ord. No. 2020-66, § 3, 12-15-20)

In addition to the uses listed in Sections 17.52.480 and 17.52.580, the following are conditional uses in an R-1 district, and shall be permitted only if approved by the board of zoning adjustments as provided in Section 17.54.130:

A.

Community facility;

B.

Community clubhouse;

C.

Parking lot, only when established to fulfill the residential parking requirements of this title for a use on an abutting lot or lots;

D.

Plant nursery or greenhouse used only for the cultivation and wholesale of plant materials;

E.

Medical or residential care facility for seven or more persons per unit as regulated in Section 17.54.133 (Conditional uses—Residential, medical care, transitional and supportive housing facilities);

F.

Licensed transitional or supportive housing for seven or more persons per unit as regulated in Section 17.54.133 (Conditional uses—Residential, medical care, transitional and supportive housing facilities);

G.

Mobilehome parks subject to the provisions provided in sections 17.52.1000 to 17.52.1065;

H.

Unattended collection box(es) placed in conjunction with an approved community facility as defined in Section 17.04.010; and

I.

Soil importing in accordance with Chapter 17.66.

(Ord. 2002-60 § 1 (part); prior gen. code § 8-26.3)

(Ord. No. 2012-58, § 9, 4-10-12; Ord. No. 2013-26, § 3, 7-16-13; Ord. No. 2019-43, § 2, 10-15-19)

(See Sections 17.52.180—17.52.320, 17.52.470 and 17.52.730.)

(Prior gen. code § 8-26.4)

Except as otherwise specified in the case of a combining district, every use in an R-1 district shall be on a building site having a median lot width not less than fifty (50) feet and an area not less than five thousand (5,000) square feet. A corner building site shall have a median lot width of not less than sixty (60) feet.

(Prior gen. code § 8-26.5)

Except as otherwise specified in the case of a combining district, the minimum requirements for yards in R-1 districts shall be as follows, subject to the provisions of Section 17.52.330:

A.

Depth of front yard: Twenty (20) feet;

B.

Depth of rear yard: Twenty (20) feet;

C.

Width of side yards: not less than five feet plus one foot for each full ten feet by which the median lot width exceeds fifty (50) feet up to a maximum requirement of ten feet, except that in every case the side yard on the street side of a corner lot shall have a width not less than ten feet.

(Prior gen. code § 8-26.6)

Section 17.08.070 notwithstanding, a rear yard may have a depth of not less than ten feet if that portion of the rear yard less than twenty (20) feet in depth is compensated by open area within the same or adjacent yards on the same building site that exceed side and rear yard requirements by an area at least equal to extent of building coverage of the twenty (20) foot, rear yard. Said compensating area shall be considered a required yard in accordance with Section 17.52.330.

(Prior gen. code § 8-26.6.1)

No dwelling shall be so oriented upon a lot in an R-1 district as to have its front or living room entrance opening into a side yard less than ten feet wide, extending from said entrance to the front yard.

(Prior gen. code § 8-26.7)

No dwelling shall have a height of more than two stories, except as provided by Section 17.52.090 nor shall any building or structure have a height in excess of twenty-five (25) feet, except as provided for in this section and by Section 17.52.090. Provided the parcel has a median lot depth of at least one hundred (100) feet, a median lot width of at least seventy (70) feet, and effective lot frontage of at least fifty (50) feet, the height of a dwelling may be increased by two feet for each full ten feet than the median lot width exceeds seventy (70) feet up to a maximum height of thirty (30) feet.

(Ord. 97-70 § 1: prior gen. code § 8-26.8)

A.

In Castro Valley only (areas within the Castro Valley Urbanized Area) the maximum floor area ratio for a one-family dwelling shall be as follows:

B.

Site Development Review Required. New construction or additions which would exceed the maximum floor area ratio or maximum square footage as provided above, may be considered and are subject to site development review.

(Ord. No. 2020-66, § 4, 12-15-20)