D.C. Mun. Regs. tit. 11-B, § 321
321.1 Court regulations control:
(a) The minimum distance between two (2) building walls on the same lot that face one another, when the space between the two (2) walls is uncovered; and
(b) The minimum area of closed courts.
SOURCE: Final Rulemaking published at 63 DCR 2447, 2650 (March 4, 2016 – Part 2).