In-Wall vent for downstairs bathroom

[Kevin Richards]

I had a plumber tell me that my downstairs bathroom was either unvernted or had a Stuard (or something like that) vent in the wall. Does anyone know what that is? Also, I thought a toilet would not flush without a vented drain… sinks.. showers.. and so on.

[Robert Stephen MortonParticipant]

Alwassle. He may be referring to a studor air admittance valve.
Trust your plumber if he is a Licensed Master Plumber.
Bob

[alwasl8Participant]

Is there a way to tell for sure if it is vented or not (or find studor vent) without tearing into walls?

[nicktheplumberParticipant]

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In reply to message posted by alwasl8:
Is there a way to tell for sure if it is vented or not (or find studor vent) without tearing into walls?

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First of all, a Studor Vent (Air Admittance Valve-AAV) is permitted by some but not all codes, for some but not all applications. So far as I am aware, neither the UPC nor the IRC permits an AAV as the sole vent for a toilet.

Second, the codes that DO permit AAVs specify that they may NOT be sealed up behind walls. They need to be accessible for two reasons: 1) to be able to check on them; and, 2) because they need a free supply of air to properly vent, and sealing them behind a wall may deprive them of that free air supply.

NtP

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