http://s1055.photobucket.com/albums/s518/BlakToothGrin/

Redo kitchen with 36" cabinets tight to ceiling. Tore out sofit this weekend and found this. Toilet drain on second floor coming out a lot more than anticipated!

In between the joist where you can't see is a 45.

Can I replace all the cast from the toliet, to the tee in the stack with PVC or ABS? Reconfigure with 45's to compact the whole setup and get tight to the floor joists? Does it half to be 6" pipe from toilet to tee, or can I go smaller? How small?

Thanks so much for any help in advanced!

Are you sure it's 6"? Yes you can replace cast with PVC. ABS is not permitted in many areas.

Your right, toilet drain is 3" and the stack is 4". What can I do to compact the setup?

Just realized it's actually the drain for the double vanity upstairs.

Within reason you can raise pipes for more clearance but don't just start cutting joists. You need to keep the same diameter pipe, don't go to 3" and then back to 4. Can you load your picture on this site? Vanity should be 1 1/2 or 2".

I posted his picture below (see image).

BTG, You certainly can repipe the cast iron to PVC (or ABS depending on your area). The vertical stack needs to remain 4" up and through the roof and the horizontal (toilet drain) needs to remain 3" all the way to the toilet.

If you plan to remove all the cast iron above this point be sure to support the base of the stack and the horizontal piping when doing the work.

See if you can tell what type of cast iron pipe/fittings you have... service weight cast iron is marked as SV and extra heavy cast iron is marked as XH on the hubs/pipes. Then order the correct cast iron (SV or XH) x PVC shielded clamp to transition from the cast iron to the PVC (or ABS) pipe... see image. This will only be available like this from a plumbing supply house.

If you plan on simply repiping the horizontal (toilet drain) piping to the toilet then I see no issue using a few 45s and a 90 or two to bring this up as tight to the joists as you can... just be sure to leave 1/4" pitch per foot of pipe for proper drainage.

Little gained overall for the work, but it must be important enough if you are considering it, huh... ;)

More questions just let us know, OK?

Mark

Thanks for the replies guys! It has to be the vanity cause it's too tight to the wall to be the toilet. Not planning on cutting joists, just would like to get it tight to joists. The old cabinets were 30" with a 12" sofit. The new cabinets are 36" with 6" of crown molding to reach the ceiling. I paid a lot of money for the new cabinets and don't want to have to cut up the backs and tops to modify. My idea is to 45 down and to the right, 45 at the first joist to keep tight and get the horizontal run, and 45 down into a Y going into the stack. When I get home from work today, I'll check to see if it's SV or XH pipe. I will also get dimensions of everything.