TL;DR
A horizontal wet vent is a plumbing layout in which one pipe serves simultaneously as the drain for some bathroom fixtures and the vent for others, running horizontally and sized one pipe size larger than a dry vent would be. The IPC and UPC allow it for bathroom groups, letting a properly sized line from a lavatory vent a toilet and tub that connect downstream, saving considerable pipe in slab and joist construction.
What it means
A horizontal wet vent is a plumbing layout in which one pipe serves simultaneously as the drain for some bathroom fixtures and the vent for others, running horizontally and sized one pipe size larger than a dry vent would be. The IPC and UPC allow it for bathroom groups, letting a properly sized line from a lavatory vent a toilet and tub that connect downstream, saving considerable pipe in slab and joist construction. Strict rules govern fixture order, slope, and which fixture provides the vented connection, so inspectors examine these closely at rough-in.
Where it sits in the glossary
Horizontal wet vent is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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