107-74 - Modification of Permitted Use Regulations LAST AMENDED 2/2/2011 For any #development#, the City Planning Commission may grant special permits to allow #semi-detached# or #attached# #single-family residences# in R2 Districts and #attached# #single-# or #two-family residences# in R3-1 Districts. As a condition for granting such special permits, the Commission shall find that: (a) only by modifying the #residential building# type, the preservation of trees over six-inch caliper and of existing topography can be assured; (b) by inclusion of the proposed #residential building# types, better standards of privacy and usable #open space# can be achieved; and (c) if the #zoning lot# is located in the #designated open space#, the prohibition of #development# on the #designated open space# requires the permitted #development# to be concentrated in the remaining portion of the tract.