Back to Back Installation Opinions wanted

[bishoptf]

About to start 2 bathroom remodels, and would like to go with toto drakes, I have a good plumber that I work with but haven't talked the details out yet but the first thing he mentioned was the sanitary cross and to check and see if I had one and I do, currently its a 3x3x3x3x2x2 cross fixture, 2 toilets and 2 sinks/tub drainson the 2 inch inlets. Now I now I need to re-wrok the stack and have some ideas but wanted to see what others had to say.

Couple of pictures to see the space and connections:





If I cut the sanitary cross out and replace it with a 3x3x3x2x2 (dropping on of the 3" feeds for the other toilet) and then below that install a wye that feeds the second toilet. I realize I will have to build out a bigger box on top to accomodate the the wye and additional piping.

Any thoughts?

 

[Terry]

I would use a lo heel for one toilet, and bring the second one in below it on the stack with a wye. That way the flush won't run up the other trap arm and force water out of the opposing bowl.

 

[Sponsor]

 

[bishoptf]

Thanks for the quick reply, just trying to figure out how the lo heel would be plumbed ( any links to reference?). But if I replace the sanitary cross with the one that removes the other half and below that pipe the other toliet with a wye would that also work?

Not sure if the pictures are clear but right now I have a 3" sanitary cross with 2 - 2" fittings on it.

 

[Terry]

This install is done using two lo-heel 90's which tie together with a wye below. I removed a double cross.

 

[bishoptf]

This install is done using two lo-heel 90's which tie together with a wye below. I removed a double cross.

Now that I have a better picture and have thought about it over the weekend, I understand how the lo heel is working, the only problem is I'm not sure if I could get one installed, I might be able to but I need to look some more. Would there be an issue if I drop both toilets below where the current sanitary tee and put in to wye's, not opposite but on top of each other at 90 degrees, then above that would be the 2" drains for the tub/vanity. I guess you are saying I really need to vent directly at least one of the other toliets, if so then I will need to figure that one out.

Thanks for the reply.

 

[Terry]

The lav or the tub could "wet vent" the toilet(s)

 

[bishoptf]

Here are some better pictures from below and above, the green shows the path of the pipe below.

This one shows the 3x3x3x3x2x2sanitary cross with the 2 2" fittings, the 2 3 inchare the toilets, the green line is the toliet path in the next picture.



Here is the picture from above in the one bathroom:



Here is a picture from the other angle showing the other 2" fixture:



So that is what I have now, trying to come up with how to re-configure it to work when back to back, I don't think a double wye would work in my space. Still trying to figure out if I could get a lo heel to work.

Thanks in advance.