Air admittance valve usage

I am remodeling and expanding my basement bathroom. The ideal location of the new toilet is approximately 12 feet from the vent stack. There is no direct way to run a new vent stack to the outside. Would an AAV be an acceptable way to handle this situation?


See if this helps

Vent Distance (Small).jpg

That may depend on where you live, and the codes in effect in your area. AAV’s are not allowed in some areas. . .

Attached is a rough drawing of my “little” problem. I am relocating the stack washer/dryer to an inside wall and would like to add a sink next to it. Would this work?

I don’t see a toilet!

You have a “double trap” on the sink in your drawing which be incorrect.

There is no toilet!!! The big trap under the floor is for the washer/dryer combo with the stand pipe going up into the wall to fit into a recessed box for the drain and shut off valves. I want to put a sink next to the washer and wondering if I can tap into the stand pipe with a “Y” or do I have to tap into the line below the floor. If I tap into the floor line how do I vent the sink?Also does it matter which side of the washer the sink will be?

Sorry. You used the word toilet in your original post.

Add a wye fitting in the 2" line after the trap and pipe to the trap under the sink. You still need to vent the sink so an air admitance valve may be the way to go. Check with your local code authourity or simply call a plumber.


Look again…two seperate posters…two different questions…

(Hijacking in progress :stuck_out_tongue: )


You are absolutely correct. My apologies. :smiley: