[ncinqueg]

I want to install a utility sink in my laundry room utilizing the same drain/vent as what the washing machine uses now.

Current setup: Washing machine enters into a drain, goes through a p-trap, then that connects to the drain/vent pipe from the left side.

What I want to do: I want to install a sink on the left side also and run the drain along side the drywall and turn it 180 degrees and enter the same drain/vent used for the washing machine from the right side. I figured turning a pipe 180 degrees isn't a problem, so long as I have enough slope in the drain pipe.

Problem: In a perfect world, I would be able to use a double Y connection on the drain/vent (one for the washer and one for the dryer), however, the current connection for the washer is to high on the vent, so I would need to bring the utility sinks connection below the connection of the washer on that same drain/vent. Does this cause a "venting issue"? Any other ideas? Thanks!

[ncinqueg]

Attached are a couple pictures... although the second one is sideways (sorry)

[ncinqueg]

Thanks for the quick reply!
So, what you're saying is just tap the sink drain into the washer drain (prior to the washer p-trap - meaning the pipe on the left in the)... and then can you describe the venting of the sink part again?

[massplumber2008]

Hold on... pics. Helped, but now, what is the drain pipe coming off to the right?

[ncinqueg]

You're talking ab out the horizontal one near the floor? I'm not sure where that one goes (unfortunately not the original owner of the house). Could possibly be a bathroom drain from upstairs? I don't know what that one does...

[massplumber2008]

Without knowing what that pipe is it is hard to advise here... ;) Find out what the pipe is and then let me know what it is. I'll be back in a couple hours.

[ncinqueg]

I wish I had a camera that could see through drywall. This is my best guess... since the laundry room is on the side of the house with the family room (thus no other water sources near there on this level)... I can only assume its from the room directly above there... which is the master bathroom. So, it has to be either the sink or bathtub drain coming down.

[ncinqueg]

massplumber2008 - I reviewed some photos of neighbors who hae a similar model and it looks to be the drain for the shower above in the master bathroom. Does that help any?

[massplumber2008]

OK... couple ideas. My first idea is to have you remove the washing machine Ptrap and install the new sink off that pipe. Then you would just have the washing machine hose connect into the sink and be done with this with very little work... ;)

Otherwise, yes, you can connect underneath the washer drain fitting (but above "shower" fitting) and vent the new sink drain into the existing vent at about 42" off the floor (invert sanitary tee fitting)... see images.

Install a full size cleanout to the new drain (see images) and be sure that the new vent for sink pitches from the washing machine vent to the sink drain, OK?

Mark

[ncinqueg]

Ok, thanks, so would your first idea look something like this??
Except I forgot to draw a p-trap for the sink

[massplumber2008]

No, my first drawing doesn't show the sink drain connecting into the washer standpipe... shows a separate tee fitting being cut in below the washing machine drain fiting (look at image again), but above the proposed shower drain fitting... (see another image below at my next post)...

[massplumber2008]

See image below

[ncinqueg]

see image below

First, thanks for taking the time with the explanations and the drawings!

Couple issues I'm running into with this design is that there is only 6.5" of "vent" pipe" between where the washer connects to the vent and the shower drain connects to the vent. So, putting a connection between those 2 for the laundry tub could be tough. Another problem is all of the water pipping in front where this new drain would connect to the pipe. I'll try to attach a closer up image of that area in a couple minutes.

[ncinqueg]

Here are the closeups with a measuring tape

[massplumber2008]

If you are willing to cut out some of the washing machine drain piping you could install a double sanitary tee fitting and pick the sink and washer drain up that way... :)

Here, if you use a 2" PVC SHIELDED CLAMP (see image) you could cut the pipe between the shower tee and the washer tee, install a new fitting for the sink/washer and then install a coupling in the vent and join all back using the clamp as the final fitting.

[ncinqueg]

[QUOTE=massplumber2008;3389739]If you are willing to cut out some of the washing machine drain piping you could install a double sanitary tee fitting and pick the sink and washer drain up that way... :)

Wouldn't that be like my original drawing to you? Just connect the new sink drain to the washing machine drain with a tee (higher than that of the p-trap), and just have both drains running through the current washer p-trap?

[ncinqueg]

Also, stupid question, when you refer to "Add a cleanout", what does that exactly mean?

[massplumber2008]

Wouldn't be like your original drawing at all.. can't connect the sink into a washing machine standpipe, but if you installed a DOUBLE SANITARY TEE fitting into the stack you could pick up the washer ptrap and run a new Ptrap over to the sink... see image.

The cleanout is called a test tee or some call it a dandy cleanout (see image of an ABS plastic one). Install this on the pipe going to the new sink drain... just in case you need it in the future.

Mark

[ncinqueg]

I gotcha now! I just need to make sure there is enough "height" for the sink drain to slope down and still catch where the double sanitary tee is.

I've also read that using a "Y" double sanitary tee (as opposed to 90 deg angles) is better in case one of the drains ever gets clogged... it would be easier to snake out...

[massplumber2008]

Double wye cancels out the contribution of the vent... not applicable here, but I know what you are saying in terms of snaking the drain. To resolve this issue, plumbers use a special drop head tip on the end of their snakes.