Sewer Line Connection – Cast Iron to Concrete
Hi,
I’m working on an older home – 1941 that has cast iron drains that then connect to a concrete sewer line. I have dug up a small section and everything looks fine – except that the cast iron has a fair amount of rocks that have bonded to it over the years. Surprisingly the bottom half of the pipe is smooth.
While the connections look fine – i.e. no leaks – some of the grout that appears to have been smoothed over the connection has fallen off. Is the repair as simple as cleaning thoroughly and applying hydraulic cement where the old grout has fallen off? Also does anyone know how these joints were originally built?
Finally if I had to replace that cast iron section – which makes the wall penetration to the garage – any thoughts on how to best replace it and what is the best material? I’d prefer to have the least impact to the foundation wall and ensure that I don’t cause any problems to the existing cast iron drain on the interior of the home.
I’m going to get a video of the inside of the line before moving forward. I can also take photos and post if that will help.
Many thanks,
John
Replies
Photo would be good.
Are there problems with the old CI? At the sewer connect or the wall penitration?
If no problems, don't bother it unless you intend to use this opportunity to replace it all with pvc.. If that is where you are headed, then rent a CI snap cutter and cut the old CI. Make your new pvc to CI connection outside of the house with a Fernco coupling and any connection of pvc to CI inside the house with Mission band clamp couplings.
PVC to concrete pipe joints are now made with a rubber donut type fitting that goes over the pvc and seals to the inside of the concrete pipe. at least that is what I have seen used on larger diameter pipe. It is probably the same for 4" sewer pipe too.
Good advice to which I would add:
When making the snap-cut on the existing CI that penetrates the foundation, make a trial cut farther downstream than where you intend to locate the transition to PVC or ABS. Old CI can split and crack in places you did not intend, and you don't want such a crack inside the foundation.
If the CI won't snap-cut cleanly, you can use a sawzall to carefully, albeit slowly, make a clean cut. You might burn up 2 or 3 blades before you're thru, but it's worth having a clean cut.