In all Manufacturing Districts, the obstructions set forth in Sections 23-311 (Permitted obstructions in all yards, courts and open areas) and 23-341 (Permitted obstructions in required rear yards or rear yard equivalents), as well as the following obstructions shall be permitted 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 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)        Any building or portion of a building used for any permitted use, 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 and treatment of patients, or joint living-work quarters for artists) 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 M Districts with an A suffix, the height of such obstruction shall be modified so that such building shall not exceed two stories, excluding basements, nor in any event 30 feet above curb level. In addition, in all districts, decks, parapet walls, roof thickness, skylights, vegetated roofs, and weirs, shall be permitted upon such building, or portion thereof, pursuant to Section 43-42 (Permitted Obstructions);

(2)        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; or

(3)        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 which is also a required front yard or required side yard may contain any obstructions not permitted in such front yard or side yard.