Arizona CJ
New Member
I'm planning on adding a sink to a laundry room. The good news is the wall I want to put it on has the water supply lines and sewer stack for the upstairs quest bathroom in it, so easy access to hot and cold water and the stack, and the stack serves only that bathroom group (one sink, one WC) so it's well under the fixture limit. The bad news; no vent line nearby, and there's a toilet upstream, plus wet-venting between floors looks to be against code. So, I gotta vent.
The sink drain design is pretty simple; 2" P-trap arm of around 20" into a sanitary T on the stack, with a vent line going vertical from a T on the arm. Running the vent line up to join one in the attic two floors up looked to be about 95% of the work involved in this project (I'd need to open several walls, just for a start.).
My first thought was why not look into Studor or similar Air Admittance Valves (AAV) I've seen some pros mention. I was skeptical, because I see people having to be prodded to consider them. I assumed it was cost, so I figured it'd be a few hundred bucks or more. I checked usage guides, local codes, etc, and that checked out, so I decided to bite the bullet on cost and buy one. Then I got a shock; they aren't hundreds of $, but $30 to $40. I can't even buy the pipe and fittings I need for the dry vent run for that, let alone repair and repaint the walls, plus the many days of work. I could just put the Studor in the cabinet under the sink instead.
This makes me think I'm missing something here; if it's this easy and cheap, why are people so reluctant to consider them, especially when running a dry vent line would be a massive undertaking? Is there thus an unseen flaw in my plan?
The sink drain design is pretty simple; 2" P-trap arm of around 20" into a sanitary T on the stack, with a vent line going vertical from a T on the arm. Running the vent line up to join one in the attic two floors up looked to be about 95% of the work involved in this project (I'd need to open several walls, just for a start.).
My first thought was why not look into Studor or similar Air Admittance Valves (AAV) I've seen some pros mention. I was skeptical, because I see people having to be prodded to consider them. I assumed it was cost, so I figured it'd be a few hundred bucks or more. I checked usage guides, local codes, etc, and that checked out, so I decided to bite the bullet on cost and buy one. Then I got a shock; they aren't hundreds of $, but $30 to $40. I can't even buy the pipe and fittings I need for the dry vent run for that, let alone repair and repaint the walls, plus the many days of work. I could just put the Studor in the cabinet under the sink instead.
This makes me think I'm missing something here; if it's this easy and cheap, why are people so reluctant to consider them, especially when running a dry vent line would be a massive undertaking? Is there thus an unseen flaw in my plan?
