D.C. Mun. Regs. tit. 11, r. 11-764
Where an enclosed pedestrian space is provided in the C-5 (PAD) District, the space created shall meet the criteria of this section before the floor area bonus in § 762.4 can be awarded.
The space shall be directly accessible to the public and shall be located to provide direct or indirect access to the public space of the main floor of the building.
The ceiling height shall be a minimum of twenty feet (20 ft.) above any floor level of the enclosed pedestrian space.
There may be more than one (1) floor level in the enclosed pedestrian space, but inter-floor level barrier-free connections shall be required.
The average horizontal dimensions between any of the walls forming an enclosed pedestrian space shall be at least forty feet (40 ft.) wide, but at no point shall the width be less than thirty feet (30 ft.), measured at the main pedestrian circulation floor level of the space; except when an entrance to the enclosed pedestrian space is provided at the facade of the building, the width of the entrance shall be no less than twenty feet (20 ft.).
Pedestrian bridges, balconies, pennants, banners, lighting fixtures, mobiles, or other decorative elements shall be permitted overhead obstructions; provided, that they do not cover in the aggregate more than thirty percent (30%) of the floor area of the enclosed pedestrian space.
An enclosed pedestrian space shall be appropriately lighted.
Interfloor level connections, columns, or similar elements, planting, landscaping, ornamental fountains, statuary, bazaar furniture, kiosks, works of art, or other similar features shall be permitted within the enclosed pedestrian space; provided, that pedestrian circulation shall be barrier-free and shall not be hampered by the features.
D.C. Mun. Regs. tit. 11, r. 11-764