The lower fixture can revent on the next floor at 42" above the floor.
It looks like you're "getting" it.
First, thanks for creating and maintaining this very helpful forum. I've been reading it for about a week and I'm impressed with the knowledge everyone here has, and of course you willingness to assist those of us that are simply "dangerous"! lol In any event, I thought I would post my sink drain plan here to ensure I do it correctly to the extent possible. In the attached picture, you can see a drain from a new sink coming through the cinderblock wall to the left of the 4" main soil pipe. I plan to bring it on through, trap it and vent it. There is an existing vent directly above that serves a washing machine just above. A diagram of my proposed new piping is attached too. If anyone sees any reason this would be problematic please chime in. Thanks in advance!
Last edited by Terry; 07-10-2011 at 01:29 PM. Reason: pics added
As long as that upper tee is located at least 6" above the top of the washer standpipe, (the 42" requirement will probably be too low in this case, which is why they give both requirements), it will work.
thanks for the replies gentlemen! I thought that would be the case. It is also the challenge... getting up that high in an existing wall, so I will have to find a way to get to the attic just above the washer somehow. Anybody want to lend me a 4' long 2" holesaw? lol