D.C. Mun. Regs. tit. 25-F, § 607
607.1 A floor covering such as carpeting or similar material shall not be installed as a floor covering in toilet room areas where handwashing sinks, toilets, or urinals are located; refuse storage rooms; or other areas where the floor is subject to moisture.
607.2 If carpeting is installed as a floor covering in areas other than those specified in Section 607.1, it shall be:
(a) Securely attached to the floor with a durable mastic, by using a stretch and tack method, or by another similar method; and
(b) Installed tightly against the wall under the coving or installed away from the wall with a space between the carpet and the wall and with the edges of the carpet secured by metal stripping or some other means.
SOURCE: Final Rulemaking published at 60 DCR 3582 (March 15, 2013).