No dwelling shall be constructed, altered, enlarged, placed, moved or maintained and no building permit therefor shall be issued in the R-2 zone, in the R-3C zone, or in the R-3 zone unless, in addition to the minimum lot area and other requirements imposed by this Chapter, the lot contains at least the minimum area and minimum usable open space set forth in Sections 19.52.140 and 19.52.150. (Ord. 89-1 § 1, 1989.)