Plumbing newbie: Replacing a rotted out cast iron shower drain pipe.

[Tdaimler]

I'm usually pretty good at handling small DIY projects that pop up. But plumbing, beyond toilet flappers and minor sink repairs, has not been a challenge for me yet. Looks like that is about to change and I am wondering if I can get a little advice!

My basement is unfinished except for some carpet. The plumbing for the first floor is exposed. Most is cast iron. There is some PVC from where they had to tap into the existing system for an addition 10 years ago.

The cast iron pipe from our first floor shower has rusted from the inside out. Luckily this shower is hardly used so it hasn't been much of an issue except for some small rust stains on the basement carpet.

Close Up of the crack:

Overview of the pipe section:

How much of this needs to be removed to fix? Can I just take out 12 inches of pipe and replace with PVC?
What if I wanted to raise the trap up 6-12 inches. Is that even possible?
PVC is noisy, is it possible to replace with cast iron?

Any and all advice is welcome and I REALLY appreciate it! If anyone needs computer or tech advice, hopefully I can add some value back!

 

[Terry]

Without seeing how that is tied in, I would say that you can't raise the line. If you do raise the line,then the vent needs to raise with it.
Venting prevents a p-trap from siphoning. You can normally go 42" to the vent with a 1.5" line and 60" on a 2" line. You may already be overextended on the trap arm for venting. If you so install some PVC there, you will need shielded couplings to prevent the pipe from shifting over time, which creates a very small pathway when it collapses. You will also need some more support there. I would consider cutting the vertical from the shower drain and replacing the p-trap while you are at it.

Looking downstream from the shower p-trap, there is a vent 90 instead of a long turn 90.
Draining through a vent 90 is not a legal fitting, and should be changed out. You have1-1/2" galvanized pipe that has been painted.

 

[Sponsor]

 

[Tdaimler]

Thanks for the response!

Here are some better photos of the overall schematic. https://imgur.com/a/QqVmRtB

The pipe that is rotting is 2 inch cast iron.

So you think I should cut from above the p-trap? Where should I make the next cut?

Is replacing with cast iron an option or do I have to do PVC? I like that the cast iron isn't as loud, however that drain isn't used often.

Thanks.

 

[Tdaimler]

Did a shielded coupling as a temporary fix. I think I'm going to have a pro come in.

Coupling:

 

[Reach4]

Did a shielded coupling as a temporary fix. I think I'm going to have a pro come in.

That looks great!
Did you slice the rubber of the coupling, and put the seam on top?

 

[Tdaimler]

I cut about a 1 inch section of pipe out. Was able to get the rubber over without cutting it. Didn't even think about just cutting it in half. I'm a work in progress! Lol.

 

[Reach4]

I cut about a 1 inch section of pipe out. Was able to get the rubber over without cutting it. Didn't even think about just cutting it in half. I'm a work in progress! Lol.

The band can be totally opened. The rubber could get a single cut. The band can then be put on.

I think your way is probably suitable for permanent use. I am not a plumber.

I suggest you not use chemical drain cleaners going forward.

 

[hj]

The pipe is NOT "cast iron", it is thread galvanized steel. The "better photos" are too dark to be of any use, but that system was NOT installed by a real plumber.

 

[Tdaimler]

Had a plumber come out and we actually found a way worse crack on the top of one of the big pipes. As many of you suggested, this design is a mess. I'm going to have the entire area replaced.

Based on these photos, how much would you think this should cost for materials and labor? I just want to make sure I'm not being ripped off.

We want to cut from about a foot above the ground and replace everything that is exposed.

Pictures: