Good morning,

Quick venting question here -

Small powder room on first floor -- when flushing the toilet you can hear the sink trap being siphoned out. Toilet is at the end of the line, sink right before it -- sewer line travels in the basement to the other side before going out.

My question is -- assuming I use an AAV as the most practical solution to this, would it be best to add the AAV directly underneath the sink? (I'm not sure there is a ton of room due to the S-drain going straight down into the floor)

Or, alternatively could I put it in the basement --- there is a capped off tee between the toilet and the sink; would an AAV work at that location?


Thanks!

Hi Bauer

The AAV should go under the sink and needs to be 4" above the new PTRAP you will install... ;)

Mark