When we bought our house the plumbing drains for a basement bathroom were roughed in but they did not install any vent lines for them.
We have the first floor plumbing draining into the main stack which drains down into the concrete of our basement and out to the street. The basement bathroom toilet/sink/shower rough in drains tie into that main drain underneath the concrete. They are all capped right now. To properly vent with PVC would be too much demo to the upstairs so we are planning on using Air admittance valves(AAV)(Studor vents). (I can draw a picture if my explanation makes sense)
To vent the sink drain I'm planning to install an AAV inside the vanity.
How do I properly use an AAV with the shower and toilet? For the shower/toilet I'm assuming bust up the concrete, tie into that drain after the P trap with pvc, and run it up into the unfinished area and install AAV's there? Will that work?
Best Answer
So for those out there looking for an answer here is what my plumber did:
The toilet, sink, and shower were all fairly close to each other (in my case about 6 ft). He installed one AAV inside the cabinet under the sink. That is the only AAV installed. He said it has now become a "wet vent" to the toilet and shower drain.