Hello! Some of you may rememebr me form the moving a toilet thread from 2 weeks ago. I am swapping the locations of the toilet and shower. The old shower drain/vent is now removed/capped where necessary, and the new toilet drain/vent is in place. I now need to add a shower drain/vent where the toilet once was. My plan is (see included pics) to cut into the old toilet drain (3 inch PVC) and bring that down to 2 inch pipe for the shower drain (with P trap). My question is, can I use the existing vent as shown in the picture, or do I need to run a new vent line after the shower P trap? Running a new vent is not a major problem as I can tie into the tub 1.5 inch vent line near by, but I figured if I could use the vent that was used when the toilet was here, then I could save myself some work.

One more question which I think I know the answer to, but just to check, I am not breaking and code violations by bring a 3 inch pipe down to 2 inches, am I? I would say no, but just wanted to check.

As always, thanks!
Rob

http://home.comcast.net/~rdmkap/drain1.JPG

http://home.comcast.net/~rdmkap/drain2.JPG

Hi Rob, Welcome back.

I can find no fault with using the old vent. Some local codes mandate a three inch vent somewhere in the system. We put ours on the kitchen because we increased the size of the kitchen drain line to three inch since disposals became popular. So would choking the three inch vent down to two inches still do the job? Yes, I think it would. Would you still be in code? Check your local codes to find out. Cheers, Tom

So would choking the three inch vent down to two inches still do the job? Yes, I think it would. Would you still be in code? Check your local codes to find out. Cheers, Tom

Thanks Tom. And to clarify, I am not choking a 3 inch vent down to a 2 inch vent. I am choking the old three inch toilet drain line down to a 2 inch line for the shower. As per the pictures, the three inch vent will still remain (it is the one in the first pic that you can barely see going up into the wall cavity.

So I will still have a 3 inch vent going up the wall and out the roof. I was mostly wanting to make sure that the vent about 3-4 feet away that vented the toilet when it was there would be close enough to vent the shower as well once I tie it into the line as shown.

Thanks again!
Rob