Planning & EstimatingQuestion 276 of 360
You are laying out a 2-inch horizontal drainage pipe. What minimum slope does the CPC require for a pipe this size?
a.1/4 inch per foot
b.1/16 inch per foot
c.1 inch per foot
d.1/2 inch per foot
Explanation
Under CPC Table 708.1, horizontal drainage piping 2½ inches and smaller must slope at least 1/4 inch per foot (about 2%). Larger pipe may be permitted at 1/8 inch per foot. Getting the fall right on the plan prevents solids from settling and clogging the line.
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