IPC Chapter 9 — Vents

Updated Mar 26, 2026

Vent sizing, developed length limits, vent types (individual, wet, circuit, stack), AAVs, roof termination.

IPC Ch9: every trap needs vent within developed length (1.5in trap=6ft, 2in=8ft, 3in=12ft). Vent size min half drain size. Roof termination: 6in above, 10ft from windows. Wet vent: 2in min for one fixture group. AAV per ASSE 1051 where permitted. Island venting for kitchen islands.

TAGS

IPC venting trap AAV wet-vent plumbing

DETAILS

code year

2024

code system

IPC

code section

Chapter 9

SOURCES

🔗https://codes.iccsafe.org/content/IPC2021P1

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