I have 1910 colonial house with a washing machine draining into a slop sink. The slop sink periodically gets things left in it by my kids and overflows. I know the easy answer but if you have kids, you know that this can be harder than the plumbing change. Can I replace the slop sink into a vertical drain. DO I need a vent pipe to do this? I do not think that there is a vent around the sink but I could vent something by adding a vent pipe to an exterior wall. How is the vertical drain designed and what do I need to look out for in order to do this?

Thanks for your help. :confused:

I have 1910 colonial house with a washing machine draining into a slop sink. The slop sink periodically gets things left in it by my kids and overflows. I know the easy answer but if you have kids, you know that this can be harder than the plumbing change. Can I replace the slop sink into a vertical drain. DO I need a vent pipe to do this? I do not think that there is a vent around the sink but I could vent something by adding a vent pipe to an exterior wall. How is the vertical drain designed and what do I need to look out for in order to do this?

Thanks for your help. :confused:


ANY and ALL fixtures that have traps have to be vented. I've freehanded a drawing that shows the typical washer installation. The trap sets just off the floor and has at least a 36" stand pipe that you hang the hook of the washer hose in. However, there may be a way to do this using the old slop sink trap without cutting into the wall but I have to know how high the pipe coming out of the wall is from the floor. Cheers, Tom

You confirmed what I thought. A picture is worth a thousand words so I attached a picture of the screwy plumbing that is there now. It's pretty ugly but in the back of the trap is the vent! I don't think this is right but you tell me. It looks like a real cob job to me but I'm no expert. I'd like to fix this, keep the slop sink but have a stand pipe that the washer vents into. The trap looks like 10" off the ground. You should also let me know if I should get a professional in to fix this.

Whoa! You just changed your entire question. In your first post you said you wished to REPLACE the slop sink with a washer hookup. In your last post you now wish to keep the slop sink and add a washer standpipe to it.
You just complicated the whole job. I can tell you how to replace the slop sink with a washer standpipe with no sweat but to cut into the top of the trap and tee off to a sweep and then into a standpipe will require someone with some plumbing skills. You are already vented with a AAV,(Air Admitance Valve) so you will have no vent problems. Let me know what you decide. Cheers, Tom

Sorry for the confusion Tom. I just wanted to change the drainage from into the slop sink to the verical drain. Any advice you have would be appreciated.

[QUOTE=hackofalltrades]Sorry for the confusion Tom. I just wanted to change the drainage from into the slop sink to the verical drain. Any advice you have would be appreciated.[/QUOTE

I must be dense because I'm still confused about what you wish to accomplish.
Post#1 asks,"Can I replace the slop sink into a vertical drain?"
Post #2 then declares," I'd like to fix this, keep the slop sink but have a stand pipe that the washer vents into.
Post #3 tells me, " I just wanted to change the drainage from into the slop sink to the verical drain. "

Do want to keep the slop sink and add a washer stand pipe? Or do you want to replace the slop sink with a washer stand pipe?
I await post#4 with baited breath. Cheers, Tom

I want to keep the slop sink and add a washer stand pipe.

I want to keep the slop sink and add a washer stand pipe.

OK, now you're going to need a plumber. If this were my call I would leave the slop sink drain and trap alone and cut in a 2" sanitary tee 6" to center off the floor in the drain/vent line. Then I would arm out to where I want my washer to set and add a 2" trap and a 36" standpipe. You have enough room to do this beneath the existing tee and that would be the easiest to do. Good luck, Tom