Here we have a 45 year old iron drain vent pipe. I was trying to clear a clog in the bathtub drain when suddenly water began seeping out from the wall. Why? Well because the pipe has rusted through in a few places where it meets the concrete slab my ranch sits on. 
The clog is in the drain past the vent before it meets the main drain line which means water hits obstruction then backs up and comes out here to flood my house. Never had a noticable flooding issue until this weekend.
Access panel removed and we see the tub drain.
And if you'll look to your left you'll see the problematic drain vent.
The vent for the main is about 6 inches beyond it.
Because I currently don't want to rip out the only full bath in the house my plan is to jam some JB waterweld around the base of the pipe to buy me some time and make it water tight again. And then snake the pipe.
When it comes time to fix this correctly I'm assuming I'll be cutting up my concrete slab?
I'm gonna hypothesize the cast vent was installed in the slab with no protective sleeve, and the lime in your concrete ate through the cast iron.
Yes, you will be cutting up the slab. But not a huge hole. Enough to expose the pipe to get back to good metal. Then cut the pipe, slip on a no-hub connector on each side, fit in a piece of PVC, and tighten the no-hubs.
Its not a difficult job. I'd say a day and a half for the average amateur. A day to chisel away the concrete and make enough access space, and a half a day to do the actual repair and put it back together. Should only be a few hours of down time that the bath is out of commission.
Just noticed...
You've already got a PVC repair coming off that tub and tying into the cast iron. This has been a problem before.
Also, make sure those copper lines are isolated and protected from the concrete, the iron, and other copper. Looks like you've got some oxidation (rust- sort of) happening on those copper lines.
Fantastic! I was hoping you would chime in SVREX, thank you!
In reply to clutchsmoke :
That one is gonna need a lot of patience. Your access looks like it is crappy.
I doubt JB is gonna do much.
That pipe is also damaged below the surface of the concrete. It's worse then it looks. Plan on fixing soon.
Have you tried snaking it? My dad had a rental and his friend had the rental next door and they used to trade problems when one of them. Would run a snake and eventually the other guys would back up. If you're planning on leaving the area soon and you don't like your neighbor it might be something to consider
SVreX (Forum Supporter) said:
I doubt JB is gonna do much.
That pipe is also damaged below the surface of the concrete. It's worse then it looks. Plan on fixing soon.
Yeah JB was a, "Hmmm... Maybe it'll work?" type of bandaid. Turns out there really isn't much left of the pipe. Only about 1/3 of it is solid. When trying to get the drain snake to make the corner it actually shot out the backside of the pipe! Finally got the snake to cooperate after 2 hours (my first time snaking a drain) and we're back to properly draining and no flooding.
SVreX (Forum Supporter) said:
In reply to clutchsmoke :
That one is gonna need a lot of patience. Your access looks like it is crappy.
Access is pretty bad at the moment. One hand only in there. The bathtub creaks and groans very loudly so I will probably yank it out giving me way more room for pipe replacing activities.
