1163.10 MINIMUM LOT SIZES.
   (a)    Lot per area dwelling unit may be reduced by not more than forty percent (40%) of the minimum lot area required in the Official Schedule of Regulations. A planned unit development need not conform to the density requirements of Chapter 1153. A diversification of lot sizes is encouraged.
   (b)   Lot widths may be varied to allow for a variety of structural designs. It is also recommended that setbacks be varied.