18.144.050: DWELLING UNITS PER ACRE:
   A.   The maximum number of dwelling units per acre of net development area for sites under fifteen percent (15%) slope shall be as follows:
 
Zone
Number
R-1
6.5
R-S
4.5
R-E
3.0
R-A
2.0
 
Densities within the R-R, A-1 and A-2 are established by the zone classification.
   B.   The maximum number of dwelling units per area for sites with an average slope of fifteen percent (15%) or over shall be in accordance with the HD hillside development district, chapter 18.138 of this title.
   C.   "Net development area" is defined as the gross area of the site less land area required for completion of perimeter streets and/or streets required by the circulation element of the general plan and less land area within the project set aside for schools, churches, flood control improvements, and other nonresidential uses. Common open space shall be considered in calculating the gross area of the site. Public parks if included as part of the open space shall also be considered in calculating the gross area of the site. (Ord. 2136 § 3, 1990: Ord. 1000 § 52.51(D), 1955)