Help replacing cast iron toilet/shower drain.

[SuperTroye]

Hi All,
Newbie DIY guy here. I am remodeling our bathroom and moving the shower. I inspected the existing plumbing and removed the galvanized trap arm because the threads were pretty severely rusted. The trap arm was connected to the toilet drain via a threaded connection. I thought about going back with a PVC threaded adapter but it didn't feel right. So, the thought was to remove the toilet bend and replace with a PVC bend with an inlet. Now, after reading it looks like my plan does not meet code and a bad idea.

I'm sort of backed into a corner and don't know how to reconnect shower and toilet.

Here is the layout and my plan to go with PVC:

Detail of the bend:

My plan was to use this:

But I read its illegal, so I tried to see if this would work but i don't have enough room:

Here is where I am now:

Any advice would be appreciated. Again, I'm new to plumbing but have the skills to execute any plan.

Thanks All!

 

[SuperTroye]

Basically, I need an equivalent replacement for this:

 

[Sponsor]

 

[Jeff H Young]

It may have been legal when it was built or not . but its not how we do it now, the pvc wasent so bad but i Didnt like how far the threads bottomed out.
Too late now generaly you can repair something but once you go certain amount with replacing you become stuck on newer codes. I dont see a good totaly legal solution . Santee on side dosent meet code

 

[John Gayewski]

Your gonna have to go down below and tie the shower in with a seperate vent.

 

[Sylvan]

Buy a BRASS 2" Nipple and a and cut the threads off one side and buy a NO HUB coupling (Shielded) and then you can attach the PVC to the coupling. The reason for a brass nipple as it will last over 50 years

 

[John Gayewski]

Use a santee where the circle is. Then you can tie back into the vent somewhere above, and tie the drain in down low.

 

[Jeff H Young]

a little bit of demo involved . mighta been avoidable, but your old plumbing I would prefer upgraded anyway .
stack will need to be cut to do it right

 

[SuperTroye]

Ok thanks for all the help guys. I went ahead and removed the cast iron sanitary tee and vent. This is a dormer bathroom so I ran a new section of 3" pvc through the roof. The pvc in the pic is just resting on the hub below.

Would a fitting like this work? Would it meet code and vent requirements for toilet and shower?

Sketch showing proposed plumbing:

 

[Jeff H Young]

wow your getting with it! Never used that fitting myself . and think you might be under differant code , but that was a common method. should be workable but verify your code

 

[John Gayewski]

People use those. We've had inspectors not allow them. I wouldn't use one since I've never needed one.

 

[SuperTroye]

People use those. We've had inspectors not allow them. I wouldn't use one since I've never needed one.

Curious about why an inspector would not allow it? This seems like my "only" option to tie in the toilet and shower. I say only, meaning without tearing out more walls and ceilings to run all new plumbing just to correct one problem.

 

[Jeff H Young]

People use those. We've had inspectors not allow them. I wouldn't use one since I've never needed one.

Me either John , Never really seen them used on work that wasent really old , I think in practice they would function well . And in this situation it might be easier to use that fitting without breaking out walls below, but cant attest to this being a legal

 

[John Gayewski]

The inspector said it could be used if you got a letter from the manufacturer stating that it was for that specific purpose. This particular inspector did not like double fixture fittings.

 

[John Gayewski]

If I were you I'd use it. I've just not used one that's all.

 

[Jeff H Young]

The inspector said it could be used if you got a letter from the manufacturer stating that it was for that specific purpose. This particular inspector did not like double fixture fittings.

sometimes it aint worth the hassel, so as a home owner, super troye might have easy access to inspector to simply ask him. Around here the many citys in so cal it can be darn near impossible to get hold of inspectors and every little town or section of a huge county or city can be a bit differant not just calling up and getting an answer

 

[Jeff H Young]

I'd use it too as a repair. but wouldn't deliberately plan out a system with it . ESPECIALY if permitted and being inspected because I've torn out work a time or two

 

[SuperTroye]

Got the fittings and came up with a rough layout. I had to notch the framing to get this to work. The only problem here is I've lost the right side blocking support for the toilet. It seems like every option has a drawback. This is hard.

 

[wwhitney]

What is the absolute elevation difference between the top of double san-tee 2" hub inlet and the top of the hub on the trap outlet? It needs to be 2" or less for a 2" trap arm.

Also, one of your photos shows a union trap, I'm under the impression that when the trap will be inaccessible a solvent weld trap is a better choice and may be required.

Cheers, Wayne

 

[SuperTroye]

What is the absolute elevation difference between the top of double san-tee 2" hub inlet and the top of the hub on the trap outlet? It needs to be 2" or less for a 2" trap arm.

Also, one of your photos shows a union trap, I'm under the impression that when the trap will be inaccessible a solvent weld trap is a better choice and may be required.

Cheers, Wayne

Thanks for the reply... I will check the vertical distance between the tee hub and trap and will adjust elevation of tee accordingly.

Yeah, the trap was the first thing I changed from the original layout.. it was a union trap and its now a solvent weld trap.

 

[wwhitney]

Looks like the house is balloon framed? The building code may want you to install fireblocking to in the stud bays between stories, each of which should be separated from the joists bays.

What notching did you have to do?

DWV routing advice is probably too late, but other options would be, in no particular order: put a street 45 into the 2" entry on the double san-tee, try to bring the shower trap out (i.e. going upstream) at that angle with just one more 45 before the trap; rotate the double san-tee a little with a 22.5 elbow in the WC fixture drain (probably wouldn't work as you'd hit that block to the left) ; if there's space in the stud bay, route the WC drain alongside the stack and join them a little lower down with an upright wye and 45.

Cheers, Wayne