How to tie into drain stack effectively

[cwolters]

I am changing a washing machine from draining into a utility tub to a direct stack to drain into.

The drain for the upstairs sink (the dishwasher and kitchen sink drain here) is just on the other side of the wall (30" max) from where I want to put the new drain stack for the washing machine. The drain is not only going below the house to the city system but acts as a vent stack up to the roof.

Here is what I want to do, does it make sense?

Tie into the 2 inch copper drain stack about 18 inches above the floor. It is a cement basement floor and there is a drain cleanout at the base, so I will tie in just above the drain cleanout.

I am going to tie into the drain with a copper tee. It will run horizontally (slight upslope for draining of course, but not at a 45 degree angle) for a foot and have a tee coming away from the wall that I am paralleling for a drain for the new tub to drain into. The tee will continue parallel to the wall for another 20 inches and then into a 2 inch trap (90 down, 90 over, 90 up) and then go vertical for about 30 inches so the top of the new washer drain stack will be about 48 inches above the floor of the basement.

The tee that comes perpindicular from the wall to the tub drain will neck down for the tub drain after coming away from the wall a afew inches and go into the trap for the tub.

Basically, I am going to tee the new tub into a 2 inch copper path that goes from the washer, past a trap and into the existing drain stack.

I don't see any problems with this, but wanted to make sure there weren't any "be sure to...'s" that I had not thought about.

Thanks again for any feedback. I have appreciated everyone that has helped me in the past...

Chris

 

[cwolters]

Picture of proposed venting

I forgot to mention, there is also a floor drain down streem of the area I am tying into and after that it tees for the sink and shower and stool in the basement. Those have their own vent stack upstream of the shower so I don't think this is a problem for the draining being vented - the upstairs sink is still vented and the inlet area of teh washing machine will be vented by the same stack? I just want to make sure it won't drain improperly. Also, when I mention horizontal runs, there is a slope of at least 1/4" per foot so it will drain fine.

Thanks

Chris

 

[Sponsor]

 

[Deb]

Deb

Back to the drawing board. Every fixture needs a vent and it has to be within certain distances from its trap, with certain fittings, with certain....the rules on venting are very specific. The bathroom vent will not serve to vent the washer and laundry tub. You also have s-traps, which will siphon.
This is probably how I would run it:
Cut in a 2" santee not too far off the floor. Run a horizontal line to about mid way between the laundry tub and the washer location. (all drainage lines are graded 1/4" per ft.), 90 up, at about 12" install a 2" santee with the tee pointing towards the washer and immediately on top of that a 2x2x1-1/2 santee with the tee pointing to the laundry tub. For the washer, run a 2" horizontal trap arm, install a 2" p-trap and a standpipe between 18-30" tall. I recommend using a washer box. For the laundry tub, run a 1-1/2" trap arm to the approx center of the tub location and 90 out of the wall. The trap for the laundry tub will connect to this. I generally install a 2" test tee (2 way cleanout) on the vent (the pipe out of the top of the 2x2x1-1/2 santee). The vent can be 1-1/2". This vent will need to extend up through the roof by itself or connect with another vent above the flood rim level of the highest fixture.
Deb
The Pipewench

 

[cwolters]

revised intention

Thanks Deb.

I think this is what you said - I drew it out and I agree with it. I have already bought the washer box, I just wanted to know the best way to hook up a vent like this since my space is constrained and I can't run 3 vents to the roof from where I am working (due to the room above).

Thanks - if I'm way off base, just let me know...

Chris

I have a friend that says "it might be more (time and money) to do it right, but it only hurts once (delay and cost) when you do it right the first time"

 

[Terry]

Another way of plumbing the laundry tray and washer together.

The hand drawn picture above looks pretty good. Deb's explaination must have helped.​

I've done plenty like that, wet venting the laundry tray over the washer.​

It saves fittings and works well.​

​

However, in Washington, they like us to do them this way now.​

It works too. More fittings though.​

I miss the other way.​

​

 

[Deb]

Deb

Wow!
That is it. Great drawing!

Terry, interesting. I really can't see that the "revent" would really accomplish anything.

Deb
The Pipewench

 

[Terry]

Deb,
Of course it doesn't.
The inspectors don't let me do it the old way though.