Air Admittance Valves

[devans175]

I'm remodeling my basement and need to move my laundry room. All of the drain lines are already in (there was a bathroom there before) The only problem I see is that the new utility tub will be kind of far from the main stack (10 to 15 feet away) Running a new vent will be difficult, and costly. Does anyone have any opinion on using an Air Admittance Valve? Any suggestions on best practices for installing it. The model I found online is "Air Admittance Valves by STUDOR"

Also, 1.2 inch is typical for a utility tub drain, isn't it?

You help is appreciated.

[Gary Swart]

The AAV question arises here periodically, and always brings mixed comments. The simple answer to your question is, yes, the do work and it will vent your sink. The chief objection to them is that they are a mechanical device and therefore can/will fail. For that reason you must leave access to it. You still must have a "real" vent to the outside, which of course, you do. There is no pipe size 1.2". Maybe you're converting 1-1/4" to a rounded off decimal? I'd use 1-1/2" for a utility sink.

[jadnashua]

If that space was a bathroom previously, it should have been vented. You sure there isn't one, maybe burried in and old wall? Unless you are draining the washer into the sink, the standpipe for that should be 2".

[devans175]

If that space was a bathroom previously, it should have been vented. You sure there isn't one, maybe burried in and old wall? Unless you are draining the washer into the sink, the standpipe for that should be 2".

The previous fixtures were on the opposite wall, along with the main stack for the house. I have room to run the drain lines, but routing a new vent, (since the main stack is now 15 feet away) would open a whole can of worms.

There is no pipe size 1.2". Maybe you're converting 1-1/4" to a rounded off decimal? I'd use 1-1/2" for a utility sink.

Sorry, I mis-typed. I meant 1.5. I appreciate the feedback!