[Execut1ve]

I have a question concerning the installation of a washer, dryer and laundry sink in an old (1940s I believe) house. On the other side of the wall they will be installed against is a bathroom, with an old clawfoot tub directly against the wall and a sink and toilet further into the room. The reason I mention this is I would like to avoid running new plumbing all the way from the basement (this is on the second floor) and would like to make use of the plumbing from the tub if possible, as the tub is no longer in use. I am reasonably handy with a wrench and don't mind the elbow grease but I want to be sure I get it right the first time.

My concerns are drain size and vent positioning. I learned recently that code requires drains for washing machines to be 3". I don't have a 3" drain line anywhere close, so I thought I would also install a laundry sink and drain the washer into that, which is permissible by code. The laundry sink would only need a 2" drain. Can I borrow the drain from the (unused) tub for this purpose? I know there needs to be a vent in there too, any suggestions on where that would go?

Here is a picture for reference, in full MS Paint glory:


I am assuming there won't be any code issues tapping into the tub's hot/cold lines for the washer and sink. Anyone is welcome to fill in the missing plumbing between the laundry sink and tub. all advice and suggestions welcome! thanks!

 

[oh'mike]

Tubs often have 1 1/2" drains ---a washer needs a 2" drain---so you are in trouble already---

As to the water lines----1/2" is fine---but touching 60 or 70 year old threaded pipe may well lead to a repipe job---so keep that in mind when you take a wrench to vintage pipe----

 

[Execut1ve]

what does the washer drain size have to do with it? the washer will drain into the laundry sink via utility hose, and the sink will be tied into the tub drain, not the washer. does draining the washer into the laundry sink increase the drain size requirement for the laundry sink?

also I was told by a plumber friend that code required a 3" drain for washing machines - have I been misinformed?

 

[tylernt]

Either you were misinformed or this website is wrong:

http://www.engineeringtoolbox.com/drainage-fixture-unit-values-d_1077.html

EDIT: While a washer only needs 2", if the washer and that entire bathroom are all going into the same pipe, that pipe needs to be 3".

 

[Execut1ve]

All right, so a washer requires a 2" drain. I see on your chart that a laundry sink requires 1 1/2", which is the same as a bathtub. If all this is correct, then it seems I should be able to disconnect the tub drain and connect the laundry sink drain to that pipe.

 

[TheEplumber]

I would not put any sink on less then 2" and I would not put a washer on less then 2".some areas do now require 3" for washers too. So your plumber friend was probably correct for where he works.
Will your idea work? There's a good chance it will, it was done similar to that 50 years ago.....

Sent from my iPhone using DIY Forum

 

[Beepster]

All right, so a washer requires a 2" drain. I see on your chart that a laundry sink requires 1 1/2", which is the same as a bathtub. If all this is correct, then it seems I should be able to disconnect the tub drain and connect the laundry sink drain to that pipe.

Building inspectors (you have a permit, right?) don't like you trying to pull an end around on the code. I would interpret it as anything downstream from the washer must be 2" no matter what route it takes.

Do whatever Eplum tells you to.

B

 

[billman5000]

The top picture shows my laundry room setup exactly. I don't have a vent either. Washer drains into tub, tub drains into floor drain. A full washer load fills the tub about 60%, because the water can't drain as fast as the washer pumps it out. Am considering adding a vent someday. They make on-demand vents that pull in air when water is going down the drain; the vent is a small plastic dealie that goes at the top of a 2" pipe, and that pipe just has to be above the top level of the laundry tub in my case. Otherwise to get a working vent, the venting pipe has to go up thru the roof.

 

[tylernt]

They make on-demand vents that pull in air when water is going down the drain; the vent is a small plastic dealie

Ah yes, an AAV or Air Admittance Valve. Allowed by some local AHJ, disallowed by some.

 

[Execut1ve]

finally got into the bathroom to take some pictures.


Plumbing at the head of the tub. I didn't realize the taps had been removed and the water lines capped. I also didn't realize the drain line for the tub (turns out it is 1 1/2") turns and goes directly into the wall in question. I will have to investigate on the other side of the wall; there is a wardrobe in the way now that will be removed if I go ahead with this project.



Found this odd little pipe sticking out of the floor near the foot of the tub. Gas line or plumbing? I can't tell

 

[Execut1ve]

Building inspectors (you have a permit, right?) don't like you trying to pull an end around on the code. I would interpret it as anything downstream from the washer must be 2" no matter what route it takes.

Do whatever Eplum tells you to.

B

I refer to my earlier question: if a laundry sink by itself requires a 1 1/2" drain, does discharging the washing machine into it increase the size requirement of the drain?

 

[Execut1ve]

update: I pulled some drawers out of the wardrobe and had a look at the wall. I didn't see any pipes emerging, so either the drain line from the tub turns straight downward inside the wall or it just ends 0.o