This chapter shall be entitled "Single-Family Residential Zone."
(Ord. 1591 § 134, 2014)
The principal objective and purpose to be served by this zone and its application is to create a living environment of the highest standards for single-family dwellings. Other related uses contributing directly to a complete living environment are considered compatible and therefore also permitted. A further related consideration is to make it possible to more efficiently and economically design, install, and maintain all physical public service facilities in terms of size and capacity to adequately and permanently meet needs resulting from a defined intensity of land use.
(Ord. 1591 § 136, 2014)
(1) 
To accomplish the purpose of this chapter, there are established in the Single-Family Residential Zone five minimum required lot area standards with respect to each of which different related yards and open spaces and are identified on the zoning map by the designations RS-15,000, RS-9,600, RS-8,400, RS-7,200, and RS-4,000:
(a) 
The minimum required area of a lot in an area designated as RS-15,000 shall be 15,000 square feet provided, however, in the geographic area described as follows:
Property located in the S.W. 1/4 of Section 17, T22N, R4E, W.M. The real property is enclosed by the following boundaries: west of the western margin of Marine View Drive, north of the northern margin of S. 240th Street, east of the Puget Sound East Passage O.H.W., and south of the north line of the S.E. 1/4 of the S.W. 1/4 of said section as recorded in King County, Washington records. A lot containing a minimum area of 25,000 square feet may be subdivided into no more than two lots, each containing a minimum area of 12,500 square feet, provided sanitary sewer service is available to the lot.
(b) 
The minimum required area of a lot in an area designated as RS-9,600 shall be 9,600 square feet.
(c) 
The minimum required area of a lot in an area designated as RS-8,400 shall be 8,400 square feet.
(d) 
The minimum required area of a lot in an area designated as RS-7,200 shall be 7,200 square feet.
(e) 
The minimum required area of a lot in an area designated as RS-4,000 shall be 4,000 square feet.
(2) 
In a multiple-lot subdivision containing four or more lots, the minimum lot area shall be deemed to have been met if the average lot area is not less than the minimum lot area requirement of the zone in which the property is located. In computing the average square foot area of lots in a subdivision, not more than 25 percent of the number of lots may contain an area less than the prescribed minimum for the zone, but in no case shall a lot contain less area than as set forth in the following:
(a) 
In RS-15,000, 13,500 square feet of lot area;
(b) 
In RS-9,600, 8,640 square feet of lot area;
(c) 
In RS-8,400, 7,560 square feet of lot area;
(d) 
In RS-7,200, 6,400 square feet of lot area;
(e) 
In RS-4,000, 3,600 square feet of lot area; and
(3) 
Provided further, that for lots containing more than the minimum lot area required for the zone in which the property is located, not more than the following areas of such lots may be credited in determining the average lot area:
(a) 
In RS-15,000, 16,500 square feet of lot area;
(b) 
In RS-9,600, 10,560 square feet of lot area;
(c) 
In RS-8,400, 9,240 square feet of lot area;
(d) 
In RS-7,200, 7,920 square feet of lot area;
(e) 
In RS-4,000, 4,400 square feet of lot area.
(Ord. 1591 § 138, 2014)
(1) 
In lots approved before August 3, 1964, the lot area per dwelling unit shall be no less than the minimum area of a lot as required for the zone in which the property is located. In lots approved after August 3, 1964, the lot area per dwelling unit for each individual lot shall be the area of the individual lots conforming to the approved subdivision.
(2) 
In the case of a permitted duplex, the lot area per dwelling unit shall be not less than one-half of the minimum required area of the lot. If a lot has less than 7,200 square feet, and was of record on August 3, 1964, the lot area per dwelling unit for a duplex shall be not less than 3,000 square feet.
(Ord. 1591 § 139, 2014)
Every lot in a Single-Family Residential Zone shall maintain a width of not less than the following:
(1) 
The minimum width of a lot in an area designated as RS-15,000 – 80 feet;
(2) 
The minimum width of a lot in an area designated as RS-9,600 – 75 feet;
(3) 
The minimum width of a lot in an area designated as RS-8,400 – 70 feet;
(4) 
The minimum width of a lot in an area designated as RS-7,200 – 60 feet;
(5) 
The minimum width of a lot in an area designated as RS-4,000 – 40 feet.
(Ord. 1591 § 140, 2014)
Every lot in a Single-Family Residential Zone shall have a front yard with a depth of no less than 20 feet. In through lots in the RS-4,000 Zone in the Redondo Neighborhood, the front yard setback shall be measured from the street with the highest roadway classification. In cases where the street classifications are equal, the City shall give deference to the predominant development pattern of yard setbacks and driveway locations.
(Ord. 1591 § 141, 2014; Ord. 1655 § 9, 2016)
(1) 
In a Single-Family Residential Zone every lot shall have a side yard on each side of the lot.
(2) 
For lots 60 feet or more in width, the side yard shall have a width of not less than five feet on one side and 10 feet on the other side.
(3) 
For lots less than 60 feet in width, all side yards shall have a width of not less than five feet.
(Ord. 1591 § 142, 2014)
(1) 
In a Single-Family Residential Zone every lot type except through lots shall have a rear yard, except that through lots in the RS-4,000 Zone in the Redondo Neighborhood may have a rear yard with the setback measured from the street with the lower roadway classification. In cases where the street classifications are equal, the City shall give deference to the predominant development pattern of yard setbacks and driveway locations.
(2) 
For lots 6,400 square feet or more in area, the rear yard shall have a depth of not less than 20 feet.
(3) 
For lots less than 6,400 square feet in area, the rear yard shall have a depth of not less than 10 feet.
(Ord. 1591 § 143, 2014; Ord. 1655 § 10, 2016)
In a Single-Family Residential Zone no residential building or structure shall exceed a height of 30 feet.
(Ord. 1591 § 144, 2014)
(1) 
In a Single-Family Residential Zone all buildings and structures shall not cover more of the lot than the maximum lot coverage requirements provided in this section.
(2) 
The maximum lot coverage requirements provided in this section shall not apply to open areas for on-site parking and private swimming pools.
(3) 
For lots 6,400 square feet or more in area, maximum lot coverage shall be 35 percent of lot area.
(4) 
For lots less than 4,480 square feet in area, maximum lot coverage shall be 50 percent of lot area.
(5) 
For lots 4,480 to 6,399 square feet in area, maximum lot coverage shall be 2,240 square feet.
(Ord. 1591 § 145, 2014)
Placement of buildings and structures on any lot in a Single-Family Residential Zone shall conform to the following:
(1) 
Interior Lots.
(a) 
Any building or structure any portion of which contains a dwelling unit or accessory dwelling unit shall not be located closer to any property line than allowed by the yard requirements of this chapter;
(b) 
The distance between a building or structure containing a dwelling unit or accessory dwelling unit and any other buildings on the same lot shall be not less than 10 feet;
(c) 
On the rear third of a lot accessory buildings or structures not containing accessory dwelling units may be built on the lot side lines and the lot rear line; provided, not less than 10 feet of the lot rear line shall be free and clear of buildings and structures; and provided further, if the lot rears upon an alley, a garage with a vehicular entrance from the alley shall maintain a distance of not less than 15 feet from the centerline of the alley.
(2) 
Corner Lots and Reverse Corner Lots.
(a) 
Except as specified below, any building or structure containing a dwelling unit or accessory dwelling unit and any other building on the same lot shall observe a distance from any lot side line of five feet from one side and 10 feet from the side street side and the rear property line specified by this chapter;
(b) 
The distance between a building or structure containing a dwelling unit or accessory dwelling units and any other buildings on the same lot shall be not less than 10 feet;
(c) 
On the rear third of a corner lot accessory buildings or structures not containing accessory dwelling unit may be built on the lot interior side line and the lot rear line; provided, if the lot rears upon an alley, a garage with a vehicular entrance from the alley shall maintain a distance not less than 15 feet from the centerline of such alley;
(d) 
On the rear third of a reverse corner lot accessory buildings or structures not containing accessory dwelling units may be built to the lot interior side line, but no building or structure shall be erected closer to the lot rear line than five feet unless an alley intervenes, in which case accessory buildings or structures may be built to the lot rear line unless the accessory building is a garage with a vehicular entrance directly from the alley, in which case such building or structure shall maintain a distance of not less than 15 feet from the centerline of the alley;
(e) 
In all cases the width of the required side yard on the side street side shall be observed.
(Ord. 1591 § 146, 2014; Ord. 1655 § 11, 2016)
(1) 
General. Accessory dwelling units must meet all of the standards of the underlying zone in which the property is located. Additionally, accessory dwelling units shall be included in the calculation for allowable units per lot. Example: If four units is the maximum total number of units allowed on a given lot and a triplex has been developed, one ADU may be added to the lot.
(a) 
Impact Fees. All ADUs are subject to adopted impact fees. Refer to the adopted Development and Engineering Services Fee Schedule.
(b) 
Number and Configuration. A single-family residential unit or middle housing unit may have up to three ADUs per lot in the following configurations: attached ADUs, detached ADUs, or a combination of attached and/or detached ADUs.
(c) 
Design Standards. The ADU shall be complementary with the architectural style and materials of the primary residence. Components considered include materials and roof line.
(d) 
Size. The ADU must not be less than 350 square feet of gross floor area and shall not exceed 1,200 square feet of gross floor area.
(e) 
Location. An ADU may be sited at a lot line if the lot line abuts a public alley, unless the city routinely plows snow on the public alley, but all other setbacks of the underlying zone apply.
(f) 
Conversions. An ADU may be converted from legal and legal nonconforming structures existing on the effective date of the ordinance codified in this section, including but not limited to detached garages, even if they violate current code requirements for setbacks and lot coverage for the underlying zone.
(g) 
Separate Sale. An ADU may be sold or otherwise conveyed separately as a condominium unit independently from the primary unit.
(h) 
Required Permits. A property owner shall apply for both a land use permit and a building permit for necessary remodeling or construction. If the ADU is to be a rental, the property owner shall also apply for and obtain a City business license prior to renting out the unit.
(Ord. 1820 § 3, 2025)