Design & SizingQuestion 11 of 110
A 2 in horizontal fixture drain must fall a total of 5 in over its run at the code minimum slope of 1/4 in per foot. How long is the run?
a.24 ft
b.40 ft
c.20 ft
d.60 ft
Explanation
Length = fall / slope = 5 in / (1/4 in per ft) = 5 x 4 = 20 ft. Pipe 2-1/2 in and smaller uses the steeper 1/4 in per foot minimum. Dividing by 1/8 in per ft would incorrectly give 40 ft, the rate reserved for 3 in and larger pipe.
Law Reference: IPC §704.1Practice all 110 questions free — no signup required.
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