21.18.010 District purposes.
   (a)   Three residential zoning designations are established to implement the low density residential (LDR), medium density residential (MDR), and high density residential (HDR) land use designations of the general plan. Residential zoning districts are as set forth in the following paragraphs.
   (b)   Single-family Residential (R-1) Zoning Districts. The R-1 districts are established to designate areas for single-family dwellings (primarily detached) and similar and related compatible uses. Except as otherwise provided in Article VI, Chapter 21.50, one dwelling is permitted on each lot in this district. This district is further subdivided into five individual single-family categories, with the suffix indicating the minimum lot size permitted as follows:
      (1)   R-1-6,000 (minimum lot size is 6,000 square feet);
      (2)   R-1-7,500 (minimum lot size is 7,500 square feet);
      (3)   R-1-8,000 (minimum lot size is 8,000 square feet);
      (4)   R-1-10,000 (minimum lot size is 10,000 square feet); and
      (5)   R-1-15,000 (minimum lot size is 15,000 square feet).
   (c)   Medium Density Residential (R-3) Zoning District. The R-3 zoning district is established to designate areas for detached and attached residential housing types at a maximum density of fifteen units per acre, and related compatible uses.
   (d)   High Density Residential (R-4) Zoning District. The R-4 zoning district is established to designate areas for all housing types at a maximum density of twenty-eight units per acre, and related compatible uses.
(Ord. 612 Exhibit A (part), 2008).