A loading space shall have minimum dimensions of not less than twelve feet (12 ft.) in width, fifty feet (50 ft.) in length, exclusive of driveways, drive aisles, and other circulation areas, and a height of clearance of not less than fifteen feet (15 ft.). One (1) off-street loading space shall be provided and maintained on the same lot for every separate occupancy requiring delivery of goods and having a modified gross floor area of five thousand square feet (5,000 sq. ft.) or more.