replace sewage pipes from the basement ceiling

[agrena]

I have made an extension where the new sewer line was connected to an old pipe. Plastic connected to cast iron. Now it turns out there is a blockage at the joint and the cast iron piece needs to be removed. I have considered breaking up from the basement ceiling to avoid having to tear up newly laid floors, etc. How do you seal the hole, do you need to insert new reinforcement? Is there another solution? I've heard about liners but don't know how they work.

 

[Byggingenjören]

Hello!

I'm not sure if I understood correctly, but is it just a matter of taking a piece of plyfa, making a hole for the new drain pipe, screwing it up into the UK joists around the pipe, and then pouring concrete from above, waiting a day, and then unscrewing the plyfa?!

Or did I misunderstand something?

Best regards

 

[Jan-Å]

I perceive TS as wanting to build from underneath, meaning he needs to seal a hole in the basement ceiling, not from above. So how does one get the concrete to stay on the ceiling? Or that's done with the help of the plywood, I suppose, the problem is how to get the concrete under the plywood??

 

[Byggingenjören]

I perceive TS as wanting to build from below, so he needs to pour concrete into a hole in the basement ceiling, not from above. How do you get the concrete to stay on the ceiling? Or you get it with the help of the plywood, I suppose, the problem is how to get the concrete under the plywood??

Aha :blushing:

Hmm, the first thing that came to my mind, foam sealant?

Regards

 

[agrena]

A small explanation! The pipe in the ceiling runs horizontally, which means that the hole that needs to be sealed will be 2 m x 20 cm and likely 10-20 cm high around the pipe.