Waste Pipe - Leaking Coupling/Sleeve Replacement

[Dan Wolf]

How do I replace and fix this?

The base trim in my basement bathroom was soft them molded, clearly it wasn’t typical moisture. I demolished the area and found wet framing, and then realized the waste line neoprene/silicone coupling or sleeve was leaking just slightly each time the upstairs toilet was flushed. The result was, and still is, a small puddle of water around the pipe’s penetration into the concrete slab.

Is the solution as simple as removing and replacing the coupling before closing in the wall again? Please note the upper section of the vertical pip is metal while the lower section into the slab is PVC. Are there any more robust measures that are more durable than this flexible sleeve?

 

[terryplumb]

The third pic seems to show a vertical crack in the pipe ,just above the rubber coupler ,and several inches long. Is that so ,or a trick of the light ?

 

[Dan Wolf]

The third pic seems to show a vertical crack in the pipe ,just above the rubber coupler ,and several inches long. Is that so ,or a trick of the light ?

You’re correct, it’s a crack. I’m finally getting around to actively testing it as I post this. What’s me best fix? (I’m assuming a 24” coupling is less than ideal?)

 

[terryplumb]

You could cut out a section of pipe and insert a length of plastic ,as long as the section of metal ( cast iron ?) Pipe above is adequately supported.

 

[Dan Wolf]

You could cut out a section of pipe and insert a length of plastic ,as long as the section of metal ( cast iron ?) Pipe above is adequately supported.

Good point. I’m pretty handy, but haven’t cut a cast iron pipe before. Any experience on your end? Do I just budget enough time and several reciprocating saw blades? I’m comfortable being the PVC up, no problem. Thanks for the help!

 

[terryplumb]

Angle grinder would be first choice. I have ,in the distant past , used a hacksaw !! Slow progress though !!

 

[Dan Wolf]

Angle grinder would be first choice. I have ,in the distant past , used a hacksaw !! Slow progress though !!

Yup, just saw he same recommendation doing some googling? Any advice to/not to try clean, use a sealing product, and replace the coupler? Understood this isn’t the best course either.

 

[terryplumb]

If you want a ,"quick bodge" ,remove the coupler ,wrap self amalgamating tape from the bottom of the cast iron working upward and past the crack.Then fit a new coupler and band clamps .

 

[Dan Wolf]

If you want a ,"quick bodge" ,remove the coupler ,wrap self amalgamating tape from the bottom of the cast iron working upward and past the crack.Then fit a new coupler and band clamps .

Understood. Thanks again for your help and for sharing your knowledge. Hopefully I can pay it forward in the future.

 

[terryplumb]

Your welcome Dan

 

[Ian H]

It would be hard to fit a single coupler because that one probably went over the plastic while there was a hole open.

I’d cut a section out with a saw, cut it quite high but as Tery says make sure the top is supported. If you do it with a grinder you will get a big spread of rust next week.

 

[Dan Wolf]

It would be hard to fit a single coupler because that one probably went over the plastic while there was a hole open.

I’d cut a section out with a saw, cut it quite high but as Tery says make sure the top is supported. If you do it with a grinder you will get a big spread of rust next week.

Ian, just so I understand what you’re saying, could you clarify what you mean by a spread of rust? (Does using a saw as opposed to a grinder solve a problem even though it’ll take longer?)

Also, I want to understand what you and Terry mean by the pipe being supported. This is coming from the ground floor, through the floor and joists to the basement (pictured) along the foundation wall. Am I understanding that the coupler might actually be helping keep the pipe from falling lower, and when it’s loosened to repair or replace I may see it slide down along the wall? If it does what do I do?

I don’t mean pick apart both your notes and be a pain, I just want to understand (before I mistakenly do anything crazy), especially since you both clearly have more expertise and knowledge than I do.

Thanks!

 

[terryplumb]

Cast iron pipe is very ,very heavy. Originally it would have been installed going into the ground ,and supported with heavy brackets bolted to the masonry . There are no brackets visible in your pics ,and for whatever reason the cast iron has been cut ,a piece of plastic pipe inserted into the floor ,and the rubber coupler fitted to join the two. The plastic offers no support to the weight of the cast iron pipe above it. I assume there are a number of brackets keeping it position. Before cutting another section out , and subjecting it to any stress/ vibration / movement etc, it would be prudent to check the condition of the brackets / anchorage etc of whatever is keeping the vertical stack in its current position.
No idea what Ian is referring to re : spread of rust ,but he makes a good point regarding the ease of fitting a new rubber coupler if you are not cutting a section of pipe out.

 

[Ian H]

I’ve seen them a week after being cut with a grinder and all the metal dust has rusted and made a mess. If you do it with a grinder I would give it a good wash down after.

 

[bobasd]

this is a UK forum but no problems we can answer your question.

i'm assuming that thats a 4" or 3" soil pipe not a waste.

dont touch the darkened bottom 30" of the pipe - its rotten and could crumble on you.

1. the best option would probably be to eliminate all CI including the closet bend to your WC - presumably located in the room above.
then come back down in 4" or 3" PVC and use a new no-hub coupling to tie into the white PVC stub - make sure that the stub isn't slightly split because of the excess cranking thats been done on the existing no-hub.
given that this option would involve cutting out the Tee that picks up the closet bend and then tieing into the vent it might be too much work and expense.

2. after clamping the pipe above the clean-out, cut the CI pipe 6" below the hub and just above the embossed writing.
use the Milwaukee new carbide saw blade - they are great.
or use a snap cutter.
or a angle grinder - theres no big mess issues with a welders thin cutting disc.

remove the pipe below and the old no-hub fitting.
use new plastic to CI no-hubs to tie in a new length of Pvc.