The following architectural features of a building may extend into a required yard, subject to other specific provisions in this Zoning Ordinance:
(a) Cornices, canopies, eaves or other similar architectural features may project into side yards a distance not exceeding one-third of the side yard width.
(b) Open fire escapes on the side or rear of a building may project into side and rear yards a distance not to exceed four feet, six inches.
(c) Bay windows, balconies, chimneys, pilasters, uncovered stairways and necessary landings and chimneys may project a distance not exceeding fifty percent of yard requirements, provided that such features do not occupy, in the aggregate, more than one-third of the length of the building wall on which they are located.
(d) Open (i.e., unroofed) porch, steps, or terrace, provided it does not occupy more than fifty percent of the yard requirements of the yard in which it is located.
(e) An open arbor or trellis.
(f) An awning or movable canopy not to exceed ten feet in height, nor projecting more than six feet into any required yard.
(g) A retaining wall, fence or masonry wall.