Chapter 18.55
SINGLE-FAMILY RESIDENTIAL ZONE
Sections
18.55.060 Lot area per dwelling unit.
18.55.120 Permissible lot coverage.
18.55.130 Placement of buildings and structures.
18.55.140 Accessory living quarters (ALQ).
18.55.010 Title.
This chapter shall be entitled “Single-Family Residential Zone.” [Ord. 1591 § 134, 2014.]
18.55.020 Application.
This chapter shall apply to all areas zoned Single-Family Residential. [Ord. 1591 § 135, 2014.]
18.55.030 Purpose.
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.]
18.55.040 Authority.
This chapter is adopted pursuant to the provisions of chapters 35.63, 35A.63 and 36.70A
RCW and other applicable laws. [Ord. 1591 § 137, 2014.]
18.55.050 Lot area.
(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.]
18.55.060 Lot area per dwelling unit.
(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.]
18.55.070 Lot width.
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.]
18.55.080 Front yard.
Every lot in a Single-Family Residential Zone shall have a front yard with a depth of not 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. 1655 § 9, 2016: Ord. 1591 § 141, 2014.]
18.55.090 Side yard.
(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.]
18.55.100 Rear yard.
(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. 1655 § 10, 2016: Ord. 1591 § 143, 2014.]
18.55.110 Height.
In a Single-Family Residential Zone no residential building or structure shall exceed a height of 30 feet. [Ord. 1591 § 144, 2014.]
18.55.120 Permissible lot coverage.
(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.]
18.55.130 Placement of buildings and structures.
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. 1655 § 11, 2016: Ord. 1591 § 146, 2014.]
18.55.140 Accessory living quarters (ALQ).
(1) Only one ALQ is allowed per residential lot.
(2) The fee owner(s) of the property must physically reside in either the primary single-family dwelling or the accessory unit. At no time shall the ALQ and the primary single-family dwelling be rented simultaneously.
(3) The ALQ shall be designed so that the appearance preserves or complements the architectural design and style of the primary single-family residence.
(4) ALQs shall be accessed either through the entrance of the primary dwelling unit or an additional side or rear entrance.
(5) The ALQ must not be less than 350 square feet of living space. Accessory living quarters shall not exceed 800 square feet if they are: (a) detached from the primary single-family dwelling; (b) created through an addition; or (c) designed into a new structure at the time of construction. For ALQs created within an existing single-family residence, the square footage limitation on an ALQ shall be no more than 35 percent of the total square footage of the primary dwelling.
(6) To gain approval for an ALQ, a property owner shall file a completed ALQ development permit application, sign an affidavit of owner occupancy, provide an additional form of documentation such as a driver’s license or voter registration record, and apply for a building permit for necessary remodeling or construction. Falsely certifying owner occupancy or failure to comply with the terms of the ALQ land use application approval shall result in the loss of ALQ registration and certificate of occupancy.
(7) The owner occupancy affidavit shall be recorded and filed as a deed restriction with the King County Recorder before a certificate of occupancy shall be issued by the Des Moines Building Official. [Ord. 1591 § 147, 2014.]