205.1 A penthouse or rooftop structure on a single household dwelling or flat shall be permitted pursuant to Subtitle C § 1501.

205.2 A mechanical penthouse or rooftop structure with a maximum height of eighteen feet, six inches (18 ft. 6 in.) shall be permitted on a non-residential building constructed pursuant to Subtitle D §§ 203.3 through 203.6.

205.3 For all other buildings and uses, the maximum permitted height of a penthouse or rooftop structure shall be twelve feet (12 ft.) and one (1) story.

SOURCE: Final Rulemaking published at 63 DCR 2447, 2834 (March 4, 2016 – Part 2); as amended by Final Rulemaking published at 70 DCR 011297 (August 25, 2023).