Drainage, Waste & VentQuestion 88 of 360
What is the minimum diameter permitted for any vent pipe?
a.2 inches
b.1 inch
c.3 inches
d.1-1/4 inch
Explanation
No vent pipe may be less than 1-1/4 inch in diameter regardless of the drain it serves. A 1 inch vent is below the code floor. The 2 inch and 3 inch values are minimums for larger drains, not the absolute minimum for any vent.
Law Reference: 2022 California Plumbing Code (CPC) §904.0Practice all 360 questions free — no signup required.
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