638.1 Where an open court is provided in a CR District, the court shall have the following minimum dimensions:

(a)	Residential building, except hotel	Width: Three inches per foot (3 in./ft.) of height of court, but not less than ten feet (10 ft.);
(b)	Hotel and other permitted structure	Two and one-half inches per foot building (2 1/2 in./ft.) of height of court, but not less than six feet (6 ft.);

638.2 Where a closed court is provided in a CR District, the court shall have the following minimum dimensions:

(a)	Residential building, except hotel	Width: Four inches per foot (4 in./ft.) of height of court, but not less than fifteen feet (15 ft.); Area: Twice the square of the required width of court dimension; and
(b)	Hotel and other permitted structure	Width: Two and one-half inches per foot (2 1/2 in./ft.) of height of court, but not less than twelve feet (12 ft.); Area: Twice the square of the required width of court dimension.

638.3 For the purposes of this section, "residential building" shall include dwellings, flats, multiple dwellings, rooming and boarding houses, hospitals, and community-based residential facilities.

638.4 In the case of a building devoted to both residential and nonresidential uses, the minimum width and area of a court shall be computed as follows:

1. (a) When the residential and nonresidential uses are located on different floors of the building, the width and area requirements shall be computed for each use at the plane of each floor of the building; and
2. (b) When the residential and nonresidential uses are located on the same floor of the building, the width and area requirements for that plane shall be computed based on the requirements for residential buildings in §§ 638.1 and 638.2.

638.5 No required opening for the admission of light and natural ventilation shall open onto a court niche where the ratio between the width of court niche and the depth of court niche is less than two to one (2:1).

638.6 No portion of a court niche shall be farther than three feet (3 ft.) from a point where the court niche is less than three feet (3 ft.) in width.

SOURCE: § 4506.6 of the Zoning Regulations, effective May 12, 1958; as amended by: Final Rulemaking published at 27 DCR 2066, 2070 (May 16, 1980); Final Rulemaking published at 28 DCR 3482, 3503 (August 7, 1981); Final Rulemaking published at 28 DCR 4192, 4196 (September 25, 1981); and Final Rulemaking published at 47 DCR 9741-43 (December 8, 2000), incorporating by reference the text of Proposed Rulemaking published at 47 DCR 8335 (October 20, 2000).