Connecting shower drain to a pitched toilet drain, help!

[Ayo Killuminati]

So we're half way into converting a warehouse bathroom to have a gorgeous custom stand up shower when we realize the cast iron toilet drain pipe is pitched forward toward the shower instead of straight or away from it making it seemingly impossible to connect the PVC saddle to it and still have the proper pitch on the new shower drain.

The guys at my local plumbing supply who usually know everything said I'm screwed. I tried googling this in hopes of finding some new age solution that could allow me to straighten one of these pipes using some kind of flexible connector that can be buried or a wedge gasket for the saddle.

I have until today to figure this out or my contractor will do his best jointing the pipe and saddle together. I don't feel like the pitch is bad enough to require a pump but it could result in stagnant water just sitting there.

 

[Terry]

The saddle is not the way. I'm thinking more access to cut the pipe, and then the correct fittings.
The shower should be vented before going into that line.

 

[Sponsor]

 

[Ayo Killuminati]

Could you elaborate on "correct fittings"? What should we use exactly?

Is there an easy way to vent the shower drain? The toilet itself is vented directly to the right of that photo with a 3" cast iron pipe straight out the 20' high ceiling. Could I simply plug into that one? My contractor claims it's not critical to do, what would I be risking or sacrificing?

 

[Standardairconditioner]

He means to dig deeper, deep enough to be able to cut-off cast iron so you can PVC to it with a coupler.

You just have to dig enough to get a grinder or a saw-all in there.

The bottom line is that you are removing some cast iron one way or another.

 

[Ayo Killuminati]

Just confused on how this will straighten out the pitch of the toilet drain just because I'm chopping it and changing it to PVC?

 

[Ayo Killuminati]

Oh you must mean cutting the cast iron straight, great idea except all that extra digging.. Any answers regarding the shower venting?

 

[Standardairconditioner]

Just confused on how this will straighten out the pitch of the toilet drain just because I'm chopping it and changing it to PVC..

The photo you have provided isn't enough for me to see a 3D representation of your situation.

Perhaps more pics would help, or at least a good schematic.

This is why 360 virtual tours does wonders.

 

[Standardairconditioner]

Oh you must mean cutting the cast iron straight, great idea except all that extra digging.. Any answers regarding the shower venting?

That's exactly why the guys "who usually know everything said I'm screwed".

Happy digging.

Or don't do it, and abandon the project. It is your choice.

 

[Ayo Killuminati]

Is there a specific name for the type of coupler i'll need? I'm assuming there is a special one that can be buried and won't deteriorate and rot? Again the clarifications and advice is very much appreciated, the sarcasm not so much.

 

[Cacher_Chick]

A saddle connection is not legal anywhere i have done work. Like Terry stated, you need to open that up so you can make a proper connection to the horizontal waste line. A standard shower requires a 2" trap, and if a proper vent is not tied in, the trap will siphon and the sewer gas will be coming back up into the shower.

 

[Ayo Killuminati]

Have you done work in Philadelphia? My contractor is claiming they wouldn't sell it if it wasn't code. I was also trying to get clarification on why most installations use the black abs instead of PVC and he balked at the idea saying thousands install it with regular PVC. What should I be using in a CMX2 Mixed Use Commercial/Residential space? This bathroom is in a private area not for public but I will also be doing 2 commercial bathrooms so info on both would be nice.

I'm working on a 3D representation to get some ideas on venting options.

 

[Reach4]

My contractor is claiming they wouldn't sell it if it wasn't code.

That is an outlandish statement.

 

[Cacher_Chick]

If it is commercial, it should be planned, permitted, and signed off on by a licensed plumber. Contractors are notorious for trying to do work which they are not qualified to do properly, because it makes them more money.

 

[Ayo Killuminati]

Contractors know how to look up code too it's not rocket science but for this specific bathroom it is in a private area within the commercial structure which is zoned Mixed-Use. I will have the commercial restrooms signed off on however; you are correct and it is better safe than sorry.

The problem is he's installed dozens of these bathrooms and i've seen a couple of them. None "gurgle" or produce any smell and aren't vented, one doesn't even have a bend (rarely does this but to add to his point). He says as long as there is a vent in the system especially one 5feet away then it's fine. He referred to many properties he's seen that had one single vent for everything. I know it "should be" but is it really worth running a second vent tied into the toilet vent directly to the right of the toilet drain before going into that line?

 

[Reach4]

I don't feel like the pitch is bad enough to require a pump but it could result in stagnant water just sitting there.

How did the pitch thing work out?

ABS and PVC are both good, and if both are permitted locally, it is best to go with what is customary and what your contractor is good at. I think ABS is usually cheaper. It does not require a primer on its adhesive cement. PVC pipe can be foam core or solid. Solid is stronger.

Cities can and often do use saddles to connect to mains.​

 

[Ayo Killuminati]

Hey thank you for your reply Reach4! We're still paused on that and doing framing and electrical work while I decide how to go about this. As you can imagine having the client tell the contractor how to do the job can be frustrating for them but I always insist on having it done right instead of done twice. What sucks is I rented a jackhammer before already and would have to again if we are to cut the main and straighten it with a rubber coupling.

I'm still confused about that because while the pitch isn't out of control, cutting it so the top piece can sit straight would mean both sides of the pipe its attaching to is still on an angle when coupling. Would that be an adequate seal still? The benefit of course is no need for saddle, straighter connection and pitch and brand new top piece for main. Downside is rerenting the jack and returning what we got. At least it would only be a 4 hour rental!

 

[Cacher_Chick]

We cannot see your project in its entirety, but the plumbing code is very specific for good reasons. A shower which is properly plumbed will have a 2" trap, and the permitted distance between the trap and it's vent shall not exceed 8 feet. This distance is allowed for a trap arm which does not exceed the standard 1/4" per foot of pitch.
If you don't mind a trap that siphons and allows sewer gas back into the room, feel free to do it some other way. We make every effort to do it right the first time, because it costs a lot more to go back and fix it after the renovations are completed. The plumbing code is nothing more than a minimum standard to prevent future problems.

 

[Ayo Killuminati]

Thanks for the info cacher_chick! The trap is under 8ft from vent. I also checked and its true that black abs is in NJ only. PVC and Saddles are both allowed and required in Philadelphia.

 

[Bluebinky]

Thanks for the info cacher_chick! The trap is under 8ft from vent. I also checked and its true that black abs is in NJ only. PVC and Saddles are both allowed and required in Philadelphia.

Just to be sure, the shower vent needs to be before connecting to the toilet drain, otherwise it will likely siphon...
Also, remember that a vent must take off vertical (within 45 degrees of vertical) and stay vertical until 42 inches above the floor. This might involve a jog over to a wall and then back to the toilet, or something like that.