Every part of a required yard shall be open to the sky, unobstructed except for permitted accessory buildings in a rear yard, the ordinary architectural projections of skylights, sills, belt courses, cornices, chimneys, flues, and other ornamental features which project into a yard not more than two and one-half feet (21/2'), and open or lattice enclosed fire escapes, fireproof outside stairways and balconies opening upon fire towers projecting into a yard not more than five feet (5'). (Ord. 93-5, 7-6-1993, eff. 7-15-1993)