Water Supply & DistributionQuestion 56 of 120
What is the minimum nominal size normally permitted for a water service pipe serving a building?
a.1/2 in
b.5/8 in
c.1 in
d.3/4 in
Explanation
The water service pipe may not be smaller than 3/4 in regardless of what the fixture unit calculation produces. A 1/2 in service is below the code floor even for a very small single-fixture building, and 5/8 in is a meter size designation, not a standard pipe size. Requiring 1 in as the minimum is stricter than the code and would be a design choice, not a code requirement.
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