I am remodeling my bathroom, and installing a clawfoot tub. I am going to slope the floor and put in a floor drain as well. The drain for the tub and the floor drain are going to be 24" from each other, and I was planning to bring the two drain lines together using a 45 degree sanitary T.

I am going to use all 2" pvc, and I have very limited under-floor space, so my plan was to have both drains immediately go into 90's, and then connect them in the horizontal plane using the "T".

My question is if I need to have 2 p-traps, 1 for each drain, of if I can have 1 p-trap after the "T".

Also, how close does the vent line need to be to the drain, and to the p-trap? I will have to install a new vent line as well, and I am planning to use an air admittance valve because there is nowhere to go with the vent line.

Thanks in advance for the help!

Hi Cirelo

Sorry, but you will need two Ptraps here.

You want to run an 1.5" drain over to the tub and keep the vent within 3-4 feet of the PTRAP.

For the floor drain, 2" is recommended and in many states this doesn't have to be vented, but I would check requirements of your state to be sure.

If you are installing a floor drain, you should probably also look into installing a TRAP-PRIMER... keeps the trap wet at all times. Here, I usually install the trap-primer under the vanity/sink and run the 1/2" pipe over to the PTRAP (direct connect).

More questions? Let me know, OK?

Mark

In addition to Mark's advice, in my area, tubs require 2" trap and drain - but 1 1/2" vent. Definitely check with your local plumbing Code... Good luck with your project... Milo

My concern is not with the traps, ( the tub requires one and floor drains have one built in)But the fact that you wish to use one drain for both fixtures. I can see future backups coming out of the floor drain. In my area floor drains do not require a vent and discharge into the main by themselves. Cheers, Tom

Check local plumbing code, in my area 3" is the smallest floor drain allowed ,1 1/2" is allowed for tub. If you don't have to be concerned with code, check Marks's and Tom's post, both are very good advice.