D.C. Mun. Regs. tit. 12, r. 12-B1502
Current through Register Vol. 71, No. 49, December 6, 2024
Strike Section M1502.4.2 of the International Residential Code in its entirety and insert a new Section M1502.4.2 into the Residential Code in its place to read as follows:
Duct installation. Exhaust ducts shall be supported at intervals not to exceed 4 feet (1219 mm) and shall be secured in place. The insert end of the duct shall extend into the adjoining duct or fitting in the direction of airflow. Exhaust duct joints shall be sealed in accordance with Section M1601.4.1 and shall be mechanically fastened. Ducts shall not be joined with screws or similar fasteners that protrude more than 1/8 inch (3.2 mm) into the inside of the duct.
D.C. Mun. Regs. tit. 12, r. 12-B1502