You cannot "WET VENT" fixtures on different floors. A wet vent is a specific type of venting method. It uses Bathroom Group fixtures only and all of the fixtures must be on the same floor of the building. A bathroom group fixture is a toilet. A lavatory, A tub OR a shower, A bidet and a emergency floor drain located in the bath room.
What your proposing to do is tie the drains from the attic into the vents of the fixtures below. That would be an illegal installation. You need to run the drain from the attic into the 3 or 4 inch stack and vent the attic fixtures separately. Plumbing is about protecting the trap seals not just about drains....
A stack is the vertical pipe that your toilet flushes into on its way to the first floor... Above that point it is a vent.
Last edited by Ghostmaker; 05-10-2013 at 07:25 PM.
Mark, I think what you are not understanding, and correct me guys if I am wrong, please.
Your friend has to run a properly sized waste line, say 3 inch to the main waste line in the basement, and tie in to that line either vertically with a Y or horizontally with a Y and an 1/8th bend, or a combo fitting with a cleanout on the back side. He would then tie in his drains and vent the fixtures in the new bath in the usual way, and run the main 3 inch waste line out the roof. Think about how vent fittings and lines lines are directed and sloped back toward the fixture drains. If you sent waste down the main stack above the lower floor vent tie ins, you would be literally sending crap back toward your fixtures, through the branch vents.
Considering your level of knowledge, you would be much better off directing your friend to this site and let Alan, Eplumber, BeenThere, Javiles, and the Ghost, among others help him out. I know that's what I would do, and I am pretty good at plumbing, but definitely not up to Par with these guys. The most important thing in the building trades, and life, for that matter, is knowing one's limitations.
" Most people would rather die than think, and most do " Bertrand Russell
Last edited by jagans; 05-11-2013 at 10:21 PM.
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