In a Class U1 District, every structure shall have a rear yard. The least dimension of such rear yard shall be twenty percent of the depth of the lot, but such least dimension need not be less than forty feet, provided that such least dimension shall in no case be less than the height of the structure. On a corner lot, the rear line of which is identical with the side line of an interior lot, no accessory structure, if detached from the main structure, shall be erected within twenty-five feet of any street line or rear lot line. (Ord. 3053. Passed 3-14-00.)