Our washer and dryer are in our garage next to the original location of our old tank water heater. We switched to a tankless mounted above the washer early last year and now I have gained a nice chunk of floor space against the wall. I’d like to put a utility sink in that spot. Water supply would be super easy with the heater literally 2 feet away but I’m not sure about the drain.

The drain for the washer juts out of the drywall at a 45 degree angle right about the top of the washer, so several feet up the wall. I know the drain then goes straight down (abs plastic) into the foundation. No crawlspace, no basement. I can see the pipe before it enters the foundation as we had to remove some drywall to do some water damage repair (old water heater leaked).

Is it as easy as tapping into the vertical drain line for the washer with something like this product??

https://homedepot.app.link/X3xBkIrH2J

I don’t know where the p trap is for the existing drain but I’m
Assuming I need to figure that out? Would the sink require it’s own trap?

Since you've looked for a trap and assume it is under the slab, I guess you've confirmed there is not a vent running inside the wall and through the roof (the vent stack would be an ideal location for the addition of a tee)

If there is no vented stack, the drain under the slab is probably a branch and not a vented line, so cutting a wye into the drain would not do anything to get you closer to code (anyway).

You could convert the standpipe drain into the laundry tub drain - do not add another trap, the one under the slab is enough - and discharge the washer via hose into the laundry tub.

Not to code, but it will work if you add a tee to the washer standpipe. You may get soap bubbles coming up through the LT drain.

I'd skip the Furnco tee and hard pipe it with a 2" x 1 ½" tee, 1 ½" thru the wall. A "slip coupling" will assist in the install of the tee if there is no play in the drain line. Give the LT its own trap. For appearance's sake.

quote:

Originally posted by Woodman:
Since you've looked for a trap and assume it is under the slab, I guess you've confirmed there is not a vent running inside the wall and through the roof (the vent stack would be an ideal location for the addition of a tee)

If there is no vented stack, the drain under the slab is probably a branch and not a vented line, so cutting a wye into the drain would not do anything to get you closer to code (anyway).

You could convert the standpipe drain into the laundry tub drain - do not add another trap, the one under the slab is enough - and discharge the washer via hose into the laundry tub.

Not to code, but it will work if you add a tee to the washer standpipe. You may get soap bubbles coming up through the LT drain.

I'd skip the Furnco tee and hard pipe it with a 2" x 1 ½" tee, 1 ½" thru the wall. A "slip coupling" will assist in the install of the tee if there is no play in the drain line. Give the LT its own trap. For appearance's sake.

So the “best” of the easier ways is to completely hijack the washer drain below the level of the future sink so the sink drain is the only thing hooked to it and then reroute the washer drain into the sink?

Look up on the roof above the drain to see if there's a vent. You could also open up the drywall above the current drain to see if it's vented. I'd start there.

quote:

Originally posted by thumperfbc:
So the “best” of the easier ways is to completely hijack the washer drain below the level of the future sink so the sink drain is the only thing hooked to it and then reroute the washer drain into the sink?

It will sort of be to code this way, except the trap is not accessible. No reason why it would not work perfectly while keeping potential sewer gas out of the garage.

I'd might add a p-trap between the LT and the wall to make it "look" right. Aside from being double-trapped, it will then appear to be to code. As long as water-only is going down the drain, there should never be an issue. Lots of silt, mud, gravel, maybe add a clean out in case the underground trap catches too much dirt.

The double-trap will slow down the flow (between the two traps), as there will be an area of pipe without free-flowing air.

let the washer dump in to the sink , and call it good

Some further info... there IS a vent protruding from the roof for that drain and upon closer inspection the drain does not dive down into the foundation where I thought it, it actually elbows 99 degrees and disappears behind the existing drywall that hasn’t been removed, right on top of the 2x4 that sits on the concrete. I assume this elbow is the start of the trap? There is no other drain in the area.

In that case, you can cut the stack in the right place, lift it up 5", and glue a 2" tee onto it (note: tees are directional fittings). A little wiggle left-right-then centered will assure the tee is seated; the bottom joint is the important one. If you're not up to speed on glueing plastic, get some extra 1 ½" fittings and practice a little.

If there is no free play in the stack, there may be a strap you can loosen, but I'd bet it is just sitting there.

I favor the thick walled Mustee wall-mount utility sink. Frees up floor space. With a proper backing board and beefy screws, like 10 x 1.5", holding the mounting bracket in place, that tub will easily support a full load of water and a dog.

https://mustee.com/catalog/18w...erglass-laundry-tub/

quote:

Originally posted by Woodman:
In that case, you can cut the stack in the right place, lift it up 5", and glue a 2" tee onto it (note: tees are directional fittings). A little wiggle left-right-then centered will assure the tee is seated; the bottom joint is the important one. If you're not up to speed on glueing plastic, get some extra 1 ½" fittings and practice a little.

If there is no free play in the stack, there may be a strap you can loosen, but I'd bet it is just sitting there.

I favor the thick walled Mustee wall-mount utility sink. Frees up floor space. With a proper backing board and beefy screws, like 10 x 1.5", holding the mounting bracket in place, that tub will easily support a full load of water and a dog.

https://mustee.com/catalog/18w...erglass-laundry-tub/

So, cut into the stack, install a T, then plumb the drain from the sink into that T, right?

The washer drain stays where it is or goes to the sink itself? The sink doesn’t need its own trap in this scenario, correct?

I'm guessing:

The vent stack inside the wall is part of the main drain. It is a vented branch off the main drain. It would probably be 2".

Under the slab is a wye coming off the drain. Out of this wye is a p-trap and the washer standpipe.

So there are two pipes you see, the washer standpipe with has it's own trap, and the vent coming off the sewer.

You put a tee on the vent - thus turning the part below the tee into part of the sewer and everything above the tee into the vent.

The tee gets piped to the LT. You'll need a trap on the LT. The washer stays where it is, in its standpipe.

This is all guesswork based on your observations.

quote:

Originally posted by Woodman:
I'm guessing:

The vent stack inside the wall is part of the main drain. It is a vented branch off the main drain. It would probably be 2".

Under the slab is a wye coming off the drain. Out of this wye is a p-trap and the washer standpipe.

So there are two pipes you see, the washer standpipe with has it's own trap, and the vent coming off the sewer.

You put a tee on the vent - thus turning the part below the tee into part of the sewer and everything above the tee into the vent.

The tee gets piped to the LT. You'll need a trap on the LT. The washer stays where it is, in its standpipe.

This is all guesswork based on your observations.

Ohhh.... hmmm, two pipes, eh? If that’s the case I don’t know where the vent pipe is. I assumed the vent going through the roof is the same pipe that the washer is draining into. Shows how much I know (or don’t know).

Just noticed something else... peering behind the washing machine itself there is a large pipe protruding from the wall at a 90 degree angle that is capped. It’s probably 8” to the right of the standing pipe the washer drains too. Is that a clean out for the washer pipe or is it part of the vent?

Heck, all this time I thought you had the wall open.

That capped pipe is what you'll run your LT into.

quote:

Originally posted by Woodman:
Heck, all this time I thought you had the wall open.

That capped pipe is what you'll run your LT into.

Of course it is. Lol. To get to that I have to move the washer and take out Sheetrock. Sounds about right.

UNLESS you’re telling me I can use the threaded pipe itself?? I’m not that lucky, am I?

EDIT: further info... the pipe coming out of the wall is male threaded, not female. It is capped with an actual cap (female threads) and not a plug with male threading. I mention this because I just looked at the Home Depot website and all the 2” clean outs are female threads... the opposite of what I have.

EDIT 2: confirmed via attic: the pipe the washer drains into is not vented. The capped pipe close to ground kevel is the one that extends out past the roof.

So, if I understand you correctly (big IF) it is as simple as using the threaded capped cleanout pipe. I need some sort of adapter that lets me tap into the 2” line with my 1.5” sink drain (trap required at the sink) AND retains a working cleanout port, correct? Can I get a simple piece at Home Depot to accomplish that?

This message has been edited. Last edited by: thumperfbc,

Still fishing for a couple more answers.