Converting Single Vanity to Double

[Birdhouse360360]

Hello everyone, I’ve been looking through forum for a few days now to find advice on how to convert my single vanity to a double. I can’t seem to find my scenario though.

The vent, in my master bathroom on the second story, goes straight up from the tee. All others I’ve seen on here are offset.
I plan on using an AAV for the second lav as my other three bathrooms have them.

So can I add just add a tee below the existing one and run it to the new lav and add an AAV?

 

[Terry]

I would guess that you have a 1.5" pipe in the wall. We have to use a 2" pipe before we split off for a second lav.
I have done the layout below for two which allows you to still snake the drains. In your case the one arm would go forward instead of to the left and out.

Or you might get by with stacking two santee for yours. Which like I mentioned would normally be off a 2" on the wet part with 1.5" trap arms.

 

[Sponsor]

 

[Birdhouse360360]

Or you might get by with stacking two santee for yours. Which like I mentioned would normally be off a 2" on the wet part with 1.5" trap arms.

Thank you Terry. If I do it this way, would an AAV still be needed?