D.C. Mun. Regs. tit. 11, r. 11-K419
The provisions of this section establish the design requirements for all buildings and structures located in the HE zones.
Except as provided in Subtitle K § 418.2, the front of a building or structure shall extend to the property line(s) abutting the street right-of-way for not less than ninety percent (90%) of the property line and to a height of not less than twenty-five feet (25 ft.).
Whatever portion of the front of a building or structure that does not extend to the property line(s) pursuant to Subtitle K § 419.2 must extend to within twenty-five feet (25 ft.) of the front property line and to a height of not less than twenty-five feet (25 ft.).
Awnings, canopies, bay windows, and balconies may extend forward of the required building line to the extent permitted by any other regulations.
For every fifty feet (50 ft.) of uninterrupted building fa?e length, the building shall incorporate modulated and articulated building wall planes through the use of projections, recesses and reveals expressing structural bays, changes in color graphical patterns, texture, or changes in building material of the façde.
The articulation shall have a minimum change of plane of six inches (6 in.).
Façde articulation of less than two feet (2 ft.) in depth shall qualify to meet the street frontage required building line standards of Subtitle K §§ 419.2 and 419.3.
Any single articulation feature shall not exceed sixty percent (60%) of the building façde width.
Buildings with ground floor retail shall incorporate vertical elements to create a series of storefront-type bays with entrances that are no more than fifty feet (50 ft.) apart.
Security grilles shall have no less than seventy percent (70%) transparency.
Street-facing facades shall not have blank walls (without doors or windows) greater than ten feet (10 ft.) in length.
Each use within a building shall have an individual public entrance that is clearly defined and directly accessible from the public sidewalk.
Exterior display of goods and exterior storage between the building line and the front lot line is prohibited. Outdoor seating for restaurants and pedestrian-oriented accessory uses, such as flower, food, or drink stands, or other appropriate vendors, are permitted to the extent consistent with other District laws.
Windows shall cover the following minimum area of street-facing façde above the ground floor level.
TABLE K § 419.14: MINIMUM PERCENTAGE OF STREET-FACING FAçDES
| Location | Minimum Percentage | |
| Non-Residential | Residential | |
| Primary Street | 35% | 20% |
| Secondary Street | 40% | 20% |
Buildings and structures shall clearly articulate a base, middle, and top, except for row dwellings and flats.
High quality, durable materials which enhance the building and convey permanence shall be required.
The use of synthetic stucco, vinyl siding, and/or other low-grade exterior finishes is prohibited.
D.C. Mun. Regs. tit. 11, r. 11-K419