Drainage, Waste & VentQuestion 1 of 120
A horizontal 2 in fixture branch is installed at the code minimum slope. Over a developed run of 18 ft, how much total fall does the pipe have?
a.1-1/8 in
b.2-1/4 in
c.4-1/2 in
d.9 in
Explanation
Pipe 2-1/2 in and smaller requires a minimum slope of 1/4 in per ft, so 18 ft x 1/4 in = 4-1/2 in of fall. 1-1/8 in comes from using 1/16 in per ft and 2-1/4 in from using the 1/8 in per ft rate that applies only to 3 in and larger pipe. 9 in would be 1/2 in per ft, which is double the required minimum.
Law Reference: IPC §704.1Practice all 120 questions free — no signup required.
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