Need to replace cracked toilet stack

[TheGewp]

I noticed a crack in my toilet waste line today when prepping to install a wall hung Toto. It looks like i'll need to replace the whole "stack" as everything is too close to put in a quick repair.

I assume the double santee needs to become a double wye combo?

Can i replace the combo wye at the bottom with a 3x3x2 90? Or should i just match the existing setup?

It's 50 year old pipe, so i don't mind replacing it. I had the original 1.5" tub line break a few years ago too. I assume its either brittle with age or the house has shifted enough to put stress on it. Thanks!

 

[Reach4]

I assume the double santee needs to become a double wye combo?

What is feeding that double santee from the sides -- two toilets?

You might want to make a rough sketch line drawing of what exists.

 

[Sponsor]

 

[Terry]

Double wye dropping into a combo, or a long turn 90.
You can pick up the tub with a wye off the horizontal downstream of the 90.
NO on the 3x2 90 on the horizontal. That would be a really bad idea.

If you're installing an in-wall tank for a wall hung, doesn't the 3" go into the wall and not 12" away from the wall? What am I missing here?

 

[TheGewp]

Sorry, yes 2 toilets feed the tee. I am replacing WC #2 with a Toto AP wall hung to give us more space in the smaller bathroom. I was planning on removing the existing flange and making a 45 back to the wall behind WC#2.

 

[TheGewp]

This should do the trick, correct? With a 3" x 1.5" flush bushing and a couple of hub couplings?

 

[Reach4]

If you can make those fit, you should be in good shape.

I am confident there are alternatives too. With the wall mounted toilet, that exit is high. That could present alternatives for separate wyes for the two toilets. Two wyes let you independently point the ports the optimum direction.

 

[TheGewp]

If you can make those fit, you should be in good shape.

I am confident there are alternatives too. With the wall mounted toilet, that exit is high. That could present alternatives for separate wyes for the two toilets. Two wyes let you independently point the ports the optimum direction.

Yeah i am concerned about the added height. In the top right corner of first picture i posted you can see the bottom of the beam/girder that runs over the tee. Whoever installed the plumbing originally notched about 2" out of the 4x6 beam so the vent could go up to the roof through the wall above it. I have no idea how i could do this with 2 wyes and vent it properly.

 

[Terry]

Or you could have a 3" combo horizontal pointed to the first toilet, then a 3x2 wye to pick up the lav on the far side, 3x2 combo looking up for a vent, and then end it with a 90 for the last toilet.

I'm not a fan of crosses for two toilets anyway. That still leaves one vent for the toilets and one at the lav.

 

[TheGewp]

So something like this? Both Toilet connections need to be horizontal? or, less than 45 i assume?

Would a clean-out at the end (so a combo instead of a 90) be a good idea?

 

[Terry]

The cleanout at the end could be good. Normally only required at the ground though.

 

[TheGewp]

The cleanout at the end could be good. Normally only required at the ground though.

At the ground meaning the one outside the foundation about 20' down the way?

Is there any reason not to tie the lav into the end like it is now then? Or does that then make it a wet vent for toilet #2?

Would this work?

 

[Terry]

I'm sorry, looking at your first picture, is that in the crawl space? You should have an end of line cleanout then.

The last drawing on #11 also works. There are always a few ways to do things. I do like a straight drop to the main line so that the rush of water from the bowl doesn't lose speed on it's way out to the main sewer. It all works though.

 

[TheGewp]

I'm sorry, looking at your first picture, is that in the crawl space? You should have an end of line cleanout then.

The last drawing on #11 also works. There are always a few ways to do things. I do like a straight drop to the main line so that the rush of water from the bowl doesn't lose speed on it's way out to the main sewer. It all works though.

Yeah, its a crawl space. So i don't think i'll have enough clearance for the configuration in #11, would this work instead? And does the angle of the combos matter? Or can i set them on their backs at a 45 towards the toilets? Thanks!

 

[Terry]

You can angle the combos anyway you want. Looks good.

 

[TheGewp]

Sounds good, thanks!

One more quick question, is there any functional difference between these 2? It would be nice to have one this week so i can replace everything this weekend.