In all Commercial Districts, the obstructions set forth in Section 23-441 (General permitted obstruction allowances), as well as the following obstructions, shall be permitted when located within a required yard or rear yard equivalent:

(a)        In any yard or rear yard equivalent:

(1)        Fences;

(2)        Parking spaces for automobiles or bicycles, off-street, open, accessory;

(3)        Energy infrastructure equipment and accessory# mechanical equipment, provided that:

(i)    all equipment shall be subject to the applicable provisions of Section 37-20 (SPECIAL SCREENING AND ENCLOSURE PROVISIONS); and

(ii)    the height of all equipment shall not exceed a height of 23 feet above curb level;

(4)        Steps;

(5)        Walls, not exceeding eight feet in height and not roofed or part of a building.

(b)        In any rear yard or rear yard equivalent:

(1)        Balconies, unenclosed, subject to the provisions of Section 24-166;

(2)        Any building or portion of a building used for any permitted use other than residences, except that any portion of a building containing rooms used for living or sleeping purposes (other than a room in a hospital used for the care or treatment of patients) shall not be a permitted obstruction, and provided that the height of such building shall not exceed one story, excluding basement, nor in any event 23 feet above curb level. However, in C7 Districts, the height of such obstruction shall be modified so that such building shall not exceed two stories, excluding basements, nor in any even 30 feet above curb level. In addition, in all districts, decks, parapet walls, roof thickness, skylights, vegetated roofs, and weirs, pursuant to Section 33-42 (Permitted Obstructions), shall be permitted above such a building, or portion thereof;

(3)        Parking spaces for automobiles or bicycles, off-street, accessory, provided that the height of an accessory building used for such purposes and located in a required rear yard or rear yard equivalent shall not exceed 23 feet above curb level. In addition, decks, parapet walls, roof thickness, skylights, vegetated roofs, and weirs, as set forth in Section 33-42, shall be permitted above such an accessory building, or portion thereof; or

(4)        Solar energy systems affixed to solar canopies and located over parking spaces associated with public parking lots, automobile rental establishments, or commercial or public utility vehicle parking facilities, as permitted, provided that the height shall not exceed 15 feet above the level of the adjoining grade.

However, no portion of a rear yard equivalent that is also a required front yard or required side yard may contain any obstructions not permitted in such front yard or side yard.