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burked1234
Laundry Room Plumbing. Air admittance valve.

I'm going to be installing new plumbing in my basement for the Laundry setup (moving it)

Can you use an Air Admittance valve in place of a vent for the plumbing (they are permitted by code in my boro)? How do you size them for a 2" drain pipe?

This will be plumbed into a 4" secondary stack that is roof vented (and ties into the main drain under the floor) but as I understand it I should still vent this.
Roof venting is not really an option for this drain.

johnjh2o
Re: Laundry Room Plumbing. Air admittance valve.

If it's just for a clothes washer the drain should be 2" and the vent 1-1/2".

John

burked1234
Re: Laundry Room Plumbing. Air admittance valve.

thanks. are the Air Admittance valves based on vent pipe size?
Is there a benefit to sizing the vent to 2"

johnjh2o
Re: Laundry Room Plumbing. Air admittance valve.

If the vent is 1-1/2" there is no benefit to use one larger then the vent size. Many of these valves can be used on 1-1/2 or 2".

John

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