I'm finishing off my basement and need to shift some plumbing around to make room for a new wall -- and could use some help. I've read the 2009 IPC code on venting, but not being a plumber, it doesn't make complete sense.

The current drain line for the 1st floor bathroom sink comes through the floor (ceiling) and wraps around the room to the stack vent in the opposite corner. Unfortunately, it is right where the new span header has to go. Because there are drain and vent lines right below, I am hoping I can tie it into one of these, somehow.

I've attached pictures of my original layout and a couple ideas I came up with for rerouting the pipes; I don't know if either of these approaches would actually work. Can anyone offer additional insight please?

Hi TLL...

If you go with proposed #1 you will need to cut into the wall on the first floor... see diagram.

If you go proposed #2 you don't need to disturb the plumbing upstairs... see diagram.

You need to add cleanouts. I drew one in... I would add 1 or 2 more.

Joist orientation may dictate your solution...

Any questions... let me know.

Mark

(dotted/dashed lines equal vents)

Thank you for the quick reply Mark. Because the upper floor is finished, #1 really isn't viable, so I'll have to go with #2, but I have a couple of follow-ups

a. The 1.5" vent for the double sink -- can it cross-over higher, like at ceiling height? I couldn't find any info about a maximum height.


b. The cleanout makes sense, I actually forgot to draw the existing one at the 2x1.5x1.5x1.5 cross, but an additional one should've been obvious.

c. Could I just extend the current 1.5" coming from the upper floor to the new cleanout, then go 2" from the cleanout to the tee? There is only 1 fixture attached to this upper drain and it is a bathroom sink and I really don't want to rip any of the finished room up, if possible.

I do want to follow IPC code to avoid any inspector conflict, I just want to avoid additional work ;)

Thanks again
Shawn

Yup... vent can go up to ceiling before going horizontal.

If you install a 2" cleanout and then reduce to 1.5" for the upstairs sink you should be all.

Mark

Great!! Thanks again for your quick replies, I appreciate the help.

Shawn