Connecting toilet pan to broken clay pipe

[Del-inquent]

Just looking at putting in a slightly more modern (and less leaky) toilet than avocado horror currently in the downstairs WC. The collar on the clay pipe (which goes through concrete sub-floor) has been damaged in the past, about 1/3rd of it is missing and a crack runs down to about 1/2 inch from the top of the concrete. The previous owner / tradesman decide a few tubes of silicone would make it good. 

What would be the best way to overcome it without taking the entire clay pipe out? Going on a nearby bit of sub-floor I had to remove, I think they had a few dozen spare bags of cement during the build and decided to chuck them in the mix, so if I can avoid having to remove it that would be great. I'm thinking cut the whole top off the clay pipe  to about 1/4 inch above the concrete so all damage is removed then an adaptor that goes inside the clay pipe? Any tips on such an adapter?

Edited January 24 by Del-inquent

[crooksey]

If you want to do it properly just dig it out, no magic cure i'm afraid.

 

If I turned up to a job and had to finish it no fail, I would disc cut the clay pipe flat with the floor, put a flexi adapter on the new pan and force it into the clay.

[AdamSee]

As you said. Cut off the clay pipe below the crack. Use one of these to convert to a PVC pipe. Adaptors can be found from screwfix / toolstation. 

 

Link here: https://www.screwfix.com/p/mcalpine-push-fit-single-socket-drain-connector-black-110mm/4255V?kpid=4255V&cm_mmc=Google-_-Datafeed-_-Heating and Plumbing?kpid=KINASEKPID&cm_mmc=Google-_-TOKEN1-_-TOKEN2&gad_source=1&gclid=EAIaIQobChMI6-vH9J37gwMVf49QBh1wcAAyEAQYAyABEgLBHPD_BwE&gclsrc=aw.ds

 

You could use a compression style rubber adaptor. They work fine and don't restrict the internal bore. If the pipe was horizontal I would recommend that option. 

 

Alternatives could be fiberglass lining it if you think its cracked under the house. Quite pricey to do. 

[Del-inquent]

21 hours ago, AdamSee said:

As you said. Cut off the clay pipe below the crack. Use one of these to convert to a PVC pipe. Adaptors can be found from screwfix / toolstation. 

 

Link here: https://www.screwfix.com/p/mcalpine-push-fit-single-socket-drain-connector-black-110mm/4255V?kpid=4255V&cm_mmc=Google-_-Datafeed-_-Heating and Plumbing?kpid=KINASEKPID&cm_mmc=Google-_-TOKEN1-_-TOKEN2&gad_source=1&gclid=EAIaIQobChMI6-vH9J37gwMVf49QBh1wcAAyEAQYAyABEgLBHPD_BwE&gclsrc=aw.ds

 

You could use a compression style rubber adaptor. They work fine and don't restrict the internal bore. If the pipe was horizontal I would recommend that option. 

 

Alternatives could be fiberglass lining it if you think its cracked under the house. Quite pricey to do. 

That looks ideal, cheers! Stuck a camera down and had a good look and all damage seems to stop above concrete. By my thinking this only serves the single toilet and the pan connector itself is going to restrict the bore as much as that adapter.

 

id really like to have taken the clay pipe out completely but toilet has to be out and back in again within a (short) day, and the chances of that are zero with the concrete- I dug a test pit outside, the concrete around the pipe is about a foot thick round the clay 😂

[marshian]

On 26/01/2024 at 13:24, crooksey said:

If you want to do it properly just dig it out, no magic cure i'm afraid.

 

If I turned up to a job and had to finish it no fail, I would disc cut the clay pipe flat with the floor, put a flexi adapter on the new pan and force it into the clay.

 

Cut off with a disk cutter - That's what I had to do in the void underneath my suspended floor - the clay pipe was cracked (probably from when the house was built - was never going to be found till I went under the floor to insulate the pipes and between the joists) 40 years of a small leak wasn't a nice area to work in although suprisingly not smelly!!!

[Del-inquent]

On 01/02/2024 at 21:03, marshian said:

 

Cut off with a disk cutter - That's what I had to do in the void underneath my suspended floor - the clay pipe was cracked (probably from when the house was built - was never going to be found till I went under the floor to insulate the pipes and between the joists) 40 years of a small leak wasn't a nice area to work in although suprisingly not smelly!!!

You got lucky, ours stank for 3 months of airing out and that was just from the cistern water leaking on to the floorboards and joists!