18-29-902.3 Sheet lead.

   Sheet lead for vent pipe flashings shall weigh not less than 3 pounds per square foot (15 kg/m 2 ) for field-constructed flashings and not less than 2 1/2 pounds per square foot (12 kg/m 2 ) for prefabricated flashings.

18-29-903 Vent Stacks and Stack Vents.

18-29-903.1 Main vent required.

   Every sanitary drainage system receiving the discharge of a water closet shall have a main vent that is either a vent stack or a stack vent. Such vent shall run undiminished in size and as directly as possible from the building drain through to the open air above the roof.

18-29-903.2 Vent stack required.

   A vent stack or a main vent shall be installed with a soil or waste stack whenever continuous vents or other branch vents are required in two or more intervals.

18-29-903.3 Vent termination.

   Every vent stack or stack vent shall extend outdoors and terminate to the open air.

18-29-903.4 Vent connection at base.

   Every vent stack shall connect to the base of the drainage stack. The vent stack shall connect at or below the lowest horizontal branch. Where the vent stack connects to the building drain, the connection shall be located within ten pipe diameters downstream of the drainage stack.

18-29-903.5 Vent headers.

   Stack vents and vent stacks connected into a common vent header at the top of the stacks and extending to the open air at one point shall be sized in accordance with the requirements of Section 18-29-916.1. The number of fixture units shall be the sum of all fixture units on all stacks connected thereto, and the developed length shall be the longest vent length from the intersection at the base of the most distant stack to the vent terminal in the open air, as a direct extension of one stack.

(Amend Coun. J. 10-14-21, p. 37722, Art. IX, § 2)