In all Residence 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, subject to the requirements set forth in Section 23-442 (Additional permitted obstructions);

(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 community facility uses, including accessory parking spaces for bicycles within such building, provided that the height of such building shall not exceed one story, nor in any event 23 feet above curb level, and further provided that the area within such building dedicated to accessory parking spaces for bicycles shall not exceed the area permitted to be excluded from floor area, pursuant to Section 25-85 (Floor Area Exemption). In addition, decks, parapet walls, roof thickness, skylights, vegetated roofs and weirs, pursuant to Section 24-51 (Permitted Obstructions), shall be permitted above such an accessory building, or portion thereof. However, the following shall not be permitted obstructions:

(i)        in all Residence Districts, 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;

(ii)        in R1, R2, R3-1, R3A, R3X, R4-1 R4A or R4B Districts, any portion of a building used for any community facility use;

(iii)        in all Residence Districts not listed in paragraph (b)(2)(ii) of this Section, beyond 100 feet of a wide street, any portion of a building used for a community facility use other than a school, house of worship, college or university, or hospital and related facilities;

(3)        Parking spaces, off-street, accessory to a community facility use, provided that the height of an accessory building, or portion of a building used for such purposes, shall not exceed 15 feet above curb level. However, such accessory building or portion of a building shall not be a permitted obstruction in R1, R2, R3-1, R3A, R3X, R4-1, R4A or R4B Districts.

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.