D.C. Mun. Regs. tit. 11, r. 11-1606
The following provisions apply to new buildings, structures, or uses with frontage on First Street S.E. south of M Street S.E., within the CG Overlay.
Each new building shall devote not less than seventy-five percent (75%) of the gross floor area of the ground floor to retail, service, entertainment, or arts uses ("preferred uses") as permitted in §§ 701.1 through 701.5 and §§ 721.1 through 721.6 of this Title; provided, that the following uses shall not be permitted: automobile, laundry, drive-through accessory to any use, gasoline service stations, and office uses (other than those accessory to the administration, maintenance, or leasing of the building).
Preferred uses shall occupy 100% of the building's street frontage along First Street S.E., except for space devoted to building entrances or required to be devoted to fire control.
The minimum floor-to-ceiling clear height for portions of the ground floor level devoted to preferred uses shall be fourteen (14) feet.
For good cause shown, the Zoning Commission may authorize interim occupancy of the preferred use space required by § 1606.2 by non-preferred uses for up to a five (5) year period; provided, that the ground floor space is suitably designed for future occupancy by the preferred uses.
Where preferred use retail space is required under this section and provided, the requirement of 11 DCMR § 633 to provide public space at ground level shall not apply.
D.C. Mun. Regs. tit. 11, r. 11-1606