Unvented S-trap

Would anyone have a graphic showing how this S-trap could be converted to a proper arrangement using an AAV.

Simple… add a wye or sanitary tee to where the horizontal connects to the vertical, and extend the vertical up to it’s highest point with an AAV attached. Don’t forget to leave servicing space to replace the AAV every 3-5 years.


Thanks Jeff…perfect.
I assume the adjacent toilet wasn’t vented either. Is there a correction for that?

S-trap conversion.

s traps.jpg



Thanks. I assume that you would still need to add venting though.

Thanks Jeff
It looks like adding an AAV under the sink would be quite easy but adding the AAV to the toilet after the fact would be very difficult.

Correct, without venting the new setup Chris showed would still be considered an s-trap.