We would like to add a second laundry closet to our home. Currently we have one in the basement (where my mother-in-law) lives, but we would like to add one so as to minimize the need to bother her when we do laundry. The proposed location for the new laundry closet is more or less immediately above the current one. Getting gas, electrical and water supply to the new location is rather easy, but I want to make sure that drain will work. The current setup is a little funky and I want to make sure it doesn't limit what I am able to do.

Please see the attached picture for the current setup. Due to some funky plumbing by the previous owner we decided to us an AAV to vent the bar sink and the washer. Beneath the slab it ties into a shower drain and then onto the main drain. Also, please see a proposed diagram. Would this work? What size pipe will I need to use if it does?

I am hoping to address two problems here, actually. Given some other work we will be doing, it will be possible to go from using an AAV to a roof vent, which I know is preferred. Is there anyway to tie in an additional washing machine, one floor above this setup without having to tear up the concrete slab (again!).

Thanks!

You were doing just dandy until I read this,

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Beneath the slab it ties into a shower drain and then onto the main drain

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You want to discharge two washers and a bar sink, (7 fixture units) into a old 1 1/2" shower branch with a drain in the slab? That's just asking for trouble. Your venting looks fine. Do it in 2 inch and connect back to a stack or a main under the slab. Good luck, Tom

Speedball-

I need to check some photos when I get home tonight, but I think that the shower drain and the laundry drain dump into a 3" via a wye. Does that make things any better?

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Originally Posted by Stubits

Speedball-

I need to check some photos when I get home tonight, but I think that the shower drain and the laundry drain dump into a 3" via a wye. Does that make things any better?

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Sorry Stubby! You're still discharging two washers and a bar sink, (7 fixture units) into a old 1 1/2" shower branch with a drain in the slab. The size of the shower branch gives me concern about whether it will handle the volume or not, but my major concern is the shower drain located on the slab. With even a tiny bit of partial clog where do you think it will backup and overflow first. If it were anything but a shower or tub drain the weashers were dumping into you would have a little bit of safety factor, but with the drain being on the slab you'll have none. Would there be any other place to connect to? Regards, Tom

Tom-

Thanks so much for the help and patience. Let me just make sure I've described the situation correctly before we move onto a plan b!

First of all, I mispoke. It's not a shower but rather a tub. Indeed the drain and waste pipes are under the slab. Does that matter at all? Is there a distinction between tub and shower? My recollection as to how it is all tied together, which I'll confirm with pictures later tonight is that the washer standpipe is 2". The 1.5" tub/shower drain and the 2" washer standpipe connect to a 3" main(? ) drain with a wye.

As for Plan B's, what are some other options?

Thanks!

Tom-

Here are some pictures of the current setup before we closed up the walls/poured the cement. To me, it looks as though the 2" washer drain and the 1.5" shower drain both drain into the 3" main drain independently. Am I wrong? Could this/would this work?

P.S. I know my plumber screwed up and reduced the 2" washer drain down to 1.5" before tying into the 3", but I think that could be fixed pretty easily.

Oh, and just FYI, the 3" drain runs from the photo to the toilet and then to the main drain.

Any thoughts?

If the 2" pipe in the lower picture is the washer/ bar sink drain you're good to go. Looks good to me Stubby. I was concerned that the 1 1/2" drain line would choke down the flow. Go for it! Good luck, Tom

Tom-

Excellent. Thanks so much. Is this something I can do myself or would you suggest engaging a plumber? I'd probably get some help penetrating the roof, only because I have a flat roof and don't like messing with it. A couple of questions...

1) The bar sink and the basement washer each need their own vent, right?

To the vents should be located somewhere between the soil stack and the fixture's p-trap, right?

3) The vents from the basement fixtures should tie into the stack somewhere above where the new, main level washer ties in, right? Does it matter how high above they tie in?

4) What size pipe should I use for the two vents?

Thanks!

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1) The bar sink and the basement washer each need their own vent, right?

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Every fixture that has a trap must be vented. You have already addressed this,(see image)

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to the vents should be located somewhere between the soil stack and the fixture's p-trap, right?

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On a 2" line the vent must be located within a 5 foot limit between trap and stack vent.

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3) The vents from the basement fixtures should tie into the stack somewhere above where the new, main level washer ties in, right? Does it matter how high above they tie in?

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They should revent back into a existing dry vent at least 6 inches over the highest fixtures flood rim. It doesn't matter how high above.

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4) What size pipe should I use for the two vents?

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I would use 2" unless there's a problem with size.. In that case drop to 1 1/2".
Good luck and thank you for rating my answer. Tom

How do you define flood rim? In this instance, would that mean 6" above the top of the washer standpipe?

Hi all...

Flood level rim is this case will be the rim of the washing machine itself.

Stubits... are you still planning on removing the sanitary tee fitting that was reduced to 1.5" and then increased to 2"..?

Where is the vent for the tub? It's not the 2" drain (that starts out 1.5") that picks up the washing machine and lavatory... is it? If so, then you have issue, at least where I come from. Here, washing machine cannot act as a WET VENT for a tub... could siphon the trap dry and allow sewer gasses into home every time you do laundry... hmmmm..?

TOM...what are your thoughts here..? Am I missing something?

Stubits... let me know more.. ok?

MARK

Mark-

Thanks for the additional information. I understand the concept of flood level rim.

Yes, I will fix the reduced sanitary tee. The plumber apparently bought the wrong sanitary tee, 1.5" to 3" instead of 2",and he said it would work fine. Indeed it has, no problems. Same goes for the tub which is used on a daily basis. Should I replace it with a 2"x1.5"x3" tee?

More importantly, thank you for raising the issue of the vent for the tub. Honestly, I don't really know the answer, but let me give you some more info, it might make more sense to you than it does it me. Starting from the photo above, as you can see, the 1.5" bar sink and the 2" washer connect to a 3" drain, along with the 1.5" tub drain. That drain goes about 5' or so where it ties into the toilet. There is a vent stack right next to the toilet that runs up through the rough. I didn't really think much about the venting of the tub. Is it not vented at all or is it just vented poorly? Does the vent stack I am referencing do anything at all? Or is it not helping the situation here?

Here is a photo of the stack.

Hi again...

Where I'm from... the tub in unvented. In terms of venting principles the vent stack near the toilet will not come into play here... not as the water from the washing machine passes the sanitary tee fitting and creates suction on the tub ptrap and siphons it dry... that is why each trap needs to have its own vent right after the trap... at least theoretically!

Anyway, I kind of hijacked this thread. I want to know what Tom thinks. Give him awhile to respond and I'll pop back later.

PS: You cannot use sanitary tee fittings underground like that... period.

Also note that choking a 2" pipe down to 1.5" is not a problem now, but later when the pipe gets clogged by something and when snaking it it gets caught around my cable so badly that I can't retrieve the snake and have to chop the floor up to remove the snake... that make sense.. It happens. So your plumber was really WAYYYY off here!

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Originally Posted by Stubits

How do you define flood rim? In this instance, would that mean 6" above the top of the washer standpipe?

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If there are no more fixtures on the washer vent then you are correct. Change the 1 1/2" drain back to 2 inches going into the 3 inch. There's no reason the washer drains should have been choked down. Will this job be inspected? Regards,Tom

Ok, many thanks Mark. I value your opinion tremendously. For what it is worth, I don't think it would be altogether difficult to run a vent from the shower up to "new" stack I am planning to put in.

Tom- Would love your insight on the questions raised by Mark. To answer your questions, no, there will be noting above the washer at all, so I think I get where to tie in the vents. And you're right, only reason the drain got choked down was because the plumber used the wrong pieces.

Job will not likely be inspected. I am finding it harder and harder to trust the tradespeople around here and was thinking of doing it myself. In my area, only licensed plumbers can get a permit for any plumbing work at all.

Mark's sharper then I am today. He picked up on the San tee and I didn't. Vent the tub and change out the fittings from the two 45's on past the san tee that should have been a wye and not a san tee. Kudos Mark for cleaning up after the old man!
Tom

Gentlemen, thank you so much. As always, you make everything seem possible. Really appreciate your watching out for me.

Ok, so nothing new but a couple of follow-on questions.

First, sounds like the tub definitely needs to be vented. Fortunately all of this is nice and close, so it should be a problem. 1) Can I vent the tub into the washer stack, assuming it is over flood rim level of new washer? 2) Or can I tie it into the vent pipe I am going to run for the bar sink/basement washer?

Regarding the sanitary tee/wye issue, can you walk me through this a bit more? What exactly am I looking to accomplish? Also, just out of curiosity, why is a wye preferred here over the sanitary tee?

Thanks!

Hi again...

At the first picture below I have noted that the vent fitting is backward... if possible this should be changed... not critical, but just so you know... ;)

A sanitary tee fitting is not allowed on its back basically because when snaking that drain line in the future the snake could go up the drain as much as it could go down the drain... it is simply plumbing 101. No sanitary tees allowed in horizontal waste pipeing (but OK to pick up a vent).

In terms of venting the tub I would have you install a wye fitting and then a sanitary tee fitting for the vent and then the ptrap to the tub... if possible. You can tie into the vent for the washer at about 48" off the finish floor...

You decide what is reasonable here... I just want you to know as much as you can is all... ;)

MARK

Mark-

Many, many thanks. At the end of the day, if I'm going to be opening up the walls I might as well get it right, no? Even if the darn plumbers can't!

I am still not able to conceptualize the changes I need to make. What can stay? What must go? On the 3" drain do I cut it just before the 2 45's and run it straight into the wye? I am sorry, just not seeing it.