basement plumbing rough in - what are these pipes?

skypilot84

I am finishing my basement (on my own) and am trying to figure out which pipes are which. I'm pretty sure that the "flush" pipe is for the toilet, the small pipe is for the shower drain, the vertical pipe is the vent and drain for the sink but am confused about the other (larger) pipe...

Any help would be much appreciated as I don't want to screw this up and will need to draw up a diagram for the inspection/permit and all that. I'm hoping to put in a tub, toilet, and sink.

Here is a link for pictures:

http://picasaweb.google.com/maxfletcher/PlumbingPics#

Thanks in advance for the help,
Max

TheEplumber

It looks like you have a roughin for a toilet and lav. Don't really see a tub or shower drain.
Pipe in left corner appears to be toilet vent. You can probably use for a lav, depending on your code restrictions
The other 2" pipe that has CO tee appears to go to upper floor drain.
3" pipe is for WC
The other 3" looks like an end of line floor clean. It might be a back water valve though, but I'm thinking clean out.