18-29-905 Vent Connections and Grades.

18-29-905.1 Connection.

   All individual, branch vents shall connect to a vent stack, stack vent or extend to the open air.

18-29-905.2 Grade.

   All vent and branch vent pipes shall be so graded and connected as to drain back to the drainage pipe by gravity.

18-29-905.3 Vent connection to drainage system.

   Every dry vent connecting to a horizontal drain shall connect above the centerline of the horizontal drain pipe.

18-29-905.4 Vertical rise of vent.

   Every dry vent shall rise vertically to a minimum of 6 inches (150 mm) above the flood level rim of the highest trap or trapped fixture being vented.

18-29-905.5 Height above fixtures.

   A connection between a vent pipe and a vent stack or stack vent shall be made at least 6 inches (150 mm) above the flood level rim of the highest fixture served by the vent, and 42 inches (1067 mm) minimum above finished floor. Horizontal vent pipes forming branch vents, relief vents or loop vents shall be at least 6 inches (150 mm) above the flood level rim of the highest fixture served and 42 inches (1067 mm) above finished floor.

18-29-905.6 Side inlet.

   Side inlet closet bends are not permitted.

18-29-905.7 Vent for future fixtures.

   Where the drainage piping has been roughed-in for future fixtures, a rough-in connection for a vent shall be installed a minimum of one-half the diameter of the drain, but not less than the minimum size indicated in Table 18-29-916.1. The vent rough-in shall connect to the vent system. The connection shall be identified to indicate that the connection is a vent.

18-29-906 Fixture Vents.