If a habitation is located on the ground floor of a residential building, the yard of the building which lies immediately outside the habitation shall be maintained clear of any obstruction to ventilation for a distance of at least three feet (3 ft.) from the exterior wall of the building, or such further distance as may be required by any other law or regulation.
A reasonable amount of trees or shrubbery shall not be considered to be a violation of this section.
D.C. Mun. Regs. tit. 14, r. 14-509