Drainage, Waste & VentQuestion 90 of 360
A horizontal drain run is 80 feet long at 1/4 inch per foot slope. What is the total fall over the run?
a.10 inches
b.20 inches
c.40 inches
d.16 inches
Explanation
Total fall equals slope times length: 80 feet times 1/4 inch per foot = 20 inches. Ten inches would be the fall at 1/8 inch per foot, and 40 inches would require 1/2 inch per foot. Sixteen inches does not match any standard slope for this run.
Law Reference: 2022 California Plumbing Code (CPC) §708.1Practice all 360 questions free — no signup required.
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