Accessory Apartment: A dwelling unit that is secondary to the principal single household dwelling unit in terms of gross floor area, intensity of use, and physical character, but which has kitchen and bath facilities separate from the principal dwelling and may have a separate entrance.

Adult day treatment facility: A building or part of a building used for non-residential programs operated for the purpose of providing medically supervised day treatment services for adults with a developmental disability or mental disorder, totaling six (6) or more persons who are present for fewer than twenty-four (24) hours per day. An adult day treatment facility includes the following accessory uses: counseling, education, training, health, and social services for the person or persons with legal charge of individuals attending the center, including, but not limited to, any parent, spouse, sibling, child, or legal guardian of such individuals. This definition does not encompass facilities that offer drug or alcohol abuse rehabilitation services. For the purposes of this definition, the following sub-definitions apply:

  • Mental disorder - an abnormal mental condition in an individual who requires a comprehensive and relatively intensive range of mental health services in a therapeutic and structured environment if he or she is to remain in the community or if he or she is to move from twenty-four (24) hour institutional care to the community.
  • Developmental disability - a severe, chronic disability of a person that is attributable to a mental or physical impairment, or both, that is manifested before the person attains the age of twenty-two (22) years and is likely to continue indefinitely. The impairment causes substantial functional limitations in three (3) or more areas of major life activity: (a) Self-care; (b) Receptive and expressive language; (c) Learning; (d) Mobility; (e) Self-direction; (f) Capacity for independent living; or (g) Economic sufficiency. A developmental disability reflects the person's need for a combination and sequence of special, interdisciplinary or generic care, treatment, or other service, which are life-long or of extended duration, and are individually planned and coordinated.

Advisory Neighborhood Commission (ANC): A duly elected body established in accordance with § 738 of the District of Columbia Home Rule Act, approved December 24, 1973 (87 Stat. 774, 824, as amended; D.C. Official Code § 1-207.38).

Affected Advisory Neighborhood Commission: The ANC for the area within which the property that is the subject of a Zoning Commission or Board of Zoning Adjustment application or appeal is located, except that if the subject property is located on a street that serves as a boundary line between two ANCs, then the term “affected ANC” means both ANCs.

Affordable Housing: Housing where costs, including utilities and any mandatory fees for rental or mortgage principle and interest, taxes, insurance and any mandatory fees, do not exceed thirty percent (30%) of the targeted household income ranges.

Airspace Development: Development above or below streets or alleys.

Alley: A public way designated as an alley in the records of the Surveyor of the District of Columbia. An alley is not a street for the purposes of this title.

Alley Lot: see Lot, Alley.

Alterations, Structural: Any change in the permanent, physical members of a building or other structure, such as bearing walls or partitions, columns, joists, rafters, beams, or girders.

Angular Plane: A plane, based on a defined angle, that a building façade may be set up to, or behind.

Animal Boarding: Any premises, other than a veterinary hospital, pet shop, or pet grooming establishment, used as a commercial establishment for the overnight boarding and/or recurring daily care of animals for a fee. Any pet grooming establishment that permits ten (10) or more animals on the premises at a time, or that permits the overnight stay of animals, is considered an animal boarding use.

Animal Shelter: Any premises that houses and feeds stray or abandoned animals without a fee and is operated by a non-profit organization or governmental agency.

Antenna: A device used to transmit or receive communications signals. This term encompasses transmitting and receiving elements, and rotating or other directional mechanism.

Antenna Tower: A lattice-type structure, guyed or self-supporting, used to support antennas for broadcasting, transmission, reception, or other utility equipment.  Such structures shall not be deemed ground-mounted antennas as that term is used in this chapter.

Antenna, Building-mounted: Any antenna and its necessary support structure, not including an antenna tower or monopole, that is attached to the walls of, or integrated into, a building, church steeple, cooling tower, elevator bulkhead, parapet, penthouse, fire tower, tank, water tower, or other similar structure.

Antenna, Ground-mounted:  Any freestanding antenna with its base placed directly on the ground.  Ground does not include artificially elevated terrain such as berms or planter boxes but may include graded lawns, terraced landscapes that are formed from the natural grade, and at-grade patios.

Antenna, Roof-mounted: Any antenna and its necessary support structure, not including an antenna tower or monopole, that is attached to the roof of a building and which does not fall within the definition of a building-mounted antenna.

Apartment: One (1) or more habitable rooms with kitchen and bathroom facilities exclusively for the use of and under the control of the occupants of those rooms.  Control of the apartment may be by rental agreement or ownership.

Apartment House: Any building or part of a building in which there are three (3) or more apartments, providing accommodation on a monthly or longer basis.

Arcade, open:  A continuous area, located along the perimeter of a building, designed for pedestrian uses, and which adjoins a street for its entire length; and, except for structural piers, columns, or arches, is open to the street. See also:  Subtitle B, Chapter 3.

Areaway: A subsurface space adjacent to a building open at the top or protected at the top by a grating or guard that includes window wells and passageways accessing basement/cellar doors.

Art Center: A multifunctional arts use that comprises two (2) or more distinct arts design and creation uses integrated under single management.

Art Exhibition Area:A building lobby, part of a lobby, or other publicly accessible space on the basement or first or second floors of a building or an outdoor public area on private property, which space is designed and used for the public display and sale of works of art.

Art Gallery: an establishment that derives more than fifty percent (50%) of its income from the display and sale of objects of art.

Art Incubator: An arts use that:

  • Is organized under single management with a single certificate of occupancy;
  • Has as its core mission the provision of work space at a reduced cost for aspiring artists or arts organizations;
  • Provides work space that is either communal or subdivided into any number of areas;
  • May include the following uses: artist studio, administrative offices of arts organizations, legitimate theater, or media studio; and
  • Does not have any residential uses.

When located in any residential zone pursuant to Subtitle A § 101.8(a), the art incubator may have up to six (6) public sales per year for art produced in the incubator, and up to six (6) performances per year of dramatic or performance art produced in the incubator.

Artist Live-Work Space: A dwelling unit or building in which an artist or artists reside and work in an artist studio use in compliance with the requirements of one (1) of the following categories:

  • Single artist live-work space: A single dwelling unit occupied by an artist to both live and work, where a minimum of thirty percent (30%) of the gross floor area of the unit is used for an artist studio use by the artist residing therein. The minimum size of a live-work unit shall be one thousand square feet (1,000 sq. ft.). In residential zones the artist may sell art produced on site as a clearly incidental part of the live-work use; or
  • Multi-artist live-work space: A building or part of a building with two (2) or more dwelling units, with all units inhabited by artists whose primary studio is in the same structure or on the same property, but not in their unit. The studio space may be communal or may be subdivided into any number of areas.

Artist Studio: A place of work of one (1) or more persons who are engaged actively and, either gainfully or as a vocation, work in the following:

  • The fine arts, including but not limited to crafts, painting, printmaking, or sculpturing;
  • The performing and visual arts, including but not limited to dance, choreography, photography, or filmmaking;
  • Any use from the arts design and creation use category;
  • The composition of music; or
  • The recording and/or production of music, video, or other media form.

In residential zones the artist may sell art produced on site as a clearly incidental part of the studio use.