Private roads shall consist of a paved road bed constructed to minimum Department of Transportation standards for public streets, including curbs and curb drops. The minimum width of a private road shall be 38 feet from curb to curb along its entire length or, where at least three accessory parking spaces are provided for every two dwelling units and no such spaces are located within the bed of a private road, the minimum width shall be 34 feet. The entrance to any group parking facility may be narrower than such minimum widths for a distance not to exceed 20 feet, and a private road may contain a landscaped median provided the paved width of such private road meets the minimum width required exclusive of such medians. The City Planning Commission may modify the required width of a private road, pursuant to Section 26-26 (Modification and Waiver Provisions).