All,

I am installing an additional sink on the main level of my home. On the lower level, below, there is a main 3" soil stack.
I am thinking to use a 3"x2" Y connector to tie 2" drain pipe into this main soil stack.
The sink will be vented using AAV (island)

Questions:

1. Is there any particular height requirement for that tie-in (off ceiling, off floor)?
2. If not, can I tie it as close to the top of lower level as I can?
3. Can I use regular Y connector or do I have to use one with rubber gaskets and metal tie-in bands?

Water question:
I have 3/4 cold/hot water pipes in the lower level I can tie to; is there any requirement how close the new WATER tie-in has to be to the existing 1/2 pipes coming off 3/4?


Thank you

Hey Greg,

1. Is there any particular height requirement for that tie-in (off ceiling, off floor)? We stub out for a sink at 18" off the floor.

2. If not, can I tie it as close to the top of lower level as I can? I don't understand the question. The top of what lower level?

3. Can I use regular Y connector or do I have to use one with rubber gaskets and metal tie-in bands?
You don't use a wye at all. You will pick up your sink with a 3 X 2" Sanitary Tee and vent with a AAV, (see image).
[QUOTE]Water question:
I have 3/4 cold/hot water pipes in the lower level I can tie to; is there any requirement how close the new WATER tie-in has to be to the existing 1/2 pipes coming off 3/4?/QUOTE]
There is no distance requirement, however, it's recommended that no more then three fixtures be connected to a 1/2" branch. Good luck, Tom

Thanks for posting the photos. It gives exact visual of your situation...

In my region, sink drain comes out of the wall at 17" from the floor. If it is service / laundry sink than you may want to put it few inches lower since laundry sinks are deeper.

Cut your 3" PVC pipe. Cut and remove small section that is equivalent to the height of your new Sanitary Tee. Glue in 3"x2" sanitary tee. Looking at your photo, you should have enough slack in the pipe to be able to move it up so you can insert your San-Tee without using any coupling. But if you have no slack - use Flex-Seal coupling.

Height of your new San-Tee depends on how far it is from the connection your new sink. Slope should run about 1/4" per foot. So do you math.

In this scenario, there really aren't any specific requirements for water installation. Just tap-in as needed.

Tom and Milo, thank you guys.

Tom, to answer your question:

I don't understand the question. The top of what lower level?
1. The photos that you see are in the LOWER level.
2. The sink goes on the level above this one, consequently, the pipe you see on the pictures is BELOW the sink.
3. I am sorry to not forming the question right. Both of you answered that the sanitary Tee has to be installed about 18" off the floor on the lower level (where the soil stack is)

The NEW 2" sink drain pipe will be coming from the top: see right picture, where 3" soil stack turns inward to the floor of the level above, this is where the new 2" pipe will come out from the space between the ceiling and the floor. So my question was:
Can I install San-T on the straight section of the pipe (after the 2 45's you see on the right pic)? Mind you that is about 5 feet from the floor. OR do I have to take my new 2", run it down parallel to the stack, and then turn it to the right and tie it 18" off the floor? I just do not see why I have to run 2" parallel to the soil stack just to tie it in at an appropriate distance from the floor. Why couldn't I tie it higher? The sink is on the level above anyway.
Thank you for your comments.

Guys

Could you please take a look at these picture and let me know if I am progressing in the right direction.

On the pictures you see (from top to bottom)

1. Proposed tie-in of 2" drain to 3" soil stack
2. 2" drain horizontal run
3. Clean-out on the 2" and run toward kitchen island
4. Floor opening with 2" coming down to the place it has to come out of the floor.

Please comment

Thank you