7th Kahuna
Well-known member
Years ago an addition was made to the back of my building and the waste lines for the new structure were tied in via an old cleanout. The cleanout originally consisted of a cast iron sanitary tee (1.25") with a threaded plug. The elbow portion connects to a sink in the original structure. They removed the plug and threaded in an unsupported length of steel drain line.
As you might have guessed the steel has rusted out and collapsed. When I went to remove it I discovered that the weight of the 'new' line had fractured the old sanitary tee inside the wall. It appears that it has been leaking inside the wall for years.
My problem: 2/3rds of the old sanitary tee (and all its proximal downstream wasteline - horizontally oriented) is embedded in concrete beneath structure.
My plan: Eventually all this plumbing will be abandoned (and the sink relocated) so for the time being I will redirect all the waste along the face of the wall to another location and tie back into the sewer. I will then be able to abandon the old damaged sanitary tee.
My concern: Though the tee will be abandoned, if the sewer backs up, which it does from time to time (tree roots), waste will again spill into the wall. There is not enough of the old cast iron left to clamp a cap onto. I was thinking about drying out, cleaning (as best I can), and filling the pipe with high expansion spray foam. I also know there are epoxy products on the market (but only for small leaks?).
The guy at HomeDepot told me I have to jackhammer it out, no choice. I might agree except that it doesn't need to be a proper permanent repair and access is a serious issue. I remember years ago a product generically called 'plumber's buddy' or something along those lines, used for leveling fixtures and filling abandoned lines (or not). I don't know if it was water tight or even if it is still available. I am grasping at straws.
Any help or insight would be appreciated. I will be checking in from time to time as work allows.
As you might have guessed the steel has rusted out and collapsed. When I went to remove it I discovered that the weight of the 'new' line had fractured the old sanitary tee inside the wall. It appears that it has been leaking inside the wall for years.
My problem: 2/3rds of the old sanitary tee (and all its proximal downstream wasteline - horizontally oriented) is embedded in concrete beneath structure.
My plan: Eventually all this plumbing will be abandoned (and the sink relocated) so for the time being I will redirect all the waste along the face of the wall to another location and tie back into the sewer. I will then be able to abandon the old damaged sanitary tee.
My concern: Though the tee will be abandoned, if the sewer backs up, which it does from time to time (tree roots), waste will again spill into the wall. There is not enough of the old cast iron left to clamp a cap onto. I was thinking about drying out, cleaning (as best I can), and filling the pipe with high expansion spray foam. I also know there are epoxy products on the market (but only for small leaks?).
The guy at HomeDepot told me I have to jackhammer it out, no choice. I might agree except that it doesn't need to be a proper permanent repair and access is a serious issue. I remember years ago a product generically called 'plumber's buddy' or something along those lines, used for leveling fixtures and filling abandoned lines (or not). I don't know if it was water tight or even if it is still available. I am grasping at straws.
Any help or insight would be appreciated. I will be checking in from time to time as work allows.
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Isn't that true. I hate to ask for advise in that store, but it was worth what I paid for it. I'm not familiar with Plasterbond. I'll have to check it out.
