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Section P3109 Waste Stack Vent

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P3109.1 Waste Stack Vent Permitted
A waste stack shall be considered to be a vent for all of the fixtures discharging to the stack where installed in accordance with the requirements of this section.
P3109.2 Stack Installation
The waste stack shall be vertical, and both horizontal and vertical offsets shall be prohibited between the lowest fixture drain connection and the highest fixture drain connection to the stack. Every fixture drain shall connect separately to the waste stack. The stack shall not receive the discharge of water closets or urinals.
P3109.3 Stack Vent
A stack vent shall be installed for the waste stack. The size of the stack vent shall be not less than the size of the waste stack. Offsets shall be permitted in the stack vent and shall be located not less than 6 inches (152 mm) above the flood level of the highest fixture, and shall be in accordance with Section P3104.5. The stack vent shall be permitted to connect with other stack vents and vent stacks in accordance with Section P3113.3.
P3109.4 Waste Stack Size
The waste stack shall be sized based on the total discharge to the stack and the discharge within a branch interval in accordance with Table P3109.4. The waste stack shall be the same size throughout the length of the waste stack.
TABLE P3109.4
WASTE STACK VENT SIZE
STACK SIZE (inches) MAXIMUM NUMBER OF FIXTURE UNITS (d.f.u.)
Total discharge into
one branch interval
Total discharge for stack
11/2 1 2
2 2 4
21/2 No limit 8
3 No limit 24
4 No limit 50
For SI: 1 inch = 25.4 mm.

Related Code Sections

Section 913 Vents, Waste Stack Vent
A waste stack shall be considered to be a vent for all of the fixtures discharging to the stack where installed in accordance with the requirements ...
Section P3109 Vents, Waste Stack Vent
A waste stack shall be considered to be a vent for all of the fixtures discharging to the stack where installed in accordance with the requirements ...
Section P3109 Vents, Waste Stack Vent
A waste stack shall be considered to be a vent for all of the fixtures discharging to the stack where installed in accordance with the requirements ...
P3109.3 Vents, Stack Vent
A stack vent shall be installed for the waste stack. The size of the stack vent shall be not less than the size of the waste stack. Offsets shall ...
913.2 Vents, Stack Installation
The waste stack shall be vertical, and both horizontal and vertical offsets shall be prohibited between the lowest fixture drain connection ...