Soil pipe move advice

If that is clay bend leading to a clay pipe through the wall, yes - someone might need to make a new joint inside the wall.

Is this on the ground floor?

If so does the soil pipe go up to a second floor, or if a bungalow up through the roof to be ventilated?

From the photo - is that the base of the toilet next to it and if so how is the outflow to the toilet connected to this soil pipe?

The lower part of the soil pipe appears to be clay and possibly to move it a PVC extension and new PVC sweeping bend would need to be fitted under the floor. How much work this would entail depends on what is under the floorboards and how many floorboards would have to be lifted to gain suitable access. The soil pipe under the floorboards may be buried under earth or may be in a concrete foundation raft.

You may find that the builders have brought the soil pipe up beside the concrete footings which could/will extend much wider than the inside wall of the building.

Joining plastic to clay is much easier these days than in 1968 with something like

If a soil stack goes out of the roof and alternative may be to use an air admittance valve.

The only time I have seen an arrangement like that is a solid concrete floor and if that is what is below the carpet and floor boards then forget it as it is major work for little gain.

Richard

Yes.

No, it is a bungalow.

Sorry for not being clearer. The toilet itself is to the right and contains the 'U' bend which terminates in the clay 'pot' that you see in the photo. That then goes underground. The outside of the bungalow is the wall on the left where the measuring tape starts from.

To be clear the intention/hope was to move it to nearer the wall so that a new toilet would be flush with the wall and not leave the best part of a 6" gap.

It doesn't as explained above.

The soil stack is not involved. We seem to have a strange arrangement where the sewage system is shared between adjoining properties and in our case the stack is attached to the detached bungalow that is to the left of the photo.

Shouldn't be necessary, they all go into a drain the other side of the wall.

We had a similar toilet in our last house where a kitchen extension was built on the site of an old wash house and exterior toilet the toilet or at least it’s waste plumbing was retained and a new toilet was included in the extension. Like yours the clay waste was some distance from the wall and necessitated a separate cistern connected to the pan with a flush pipe. As I said before it is going to be an expensive job for little gain and basically it means you cannot use a close coupled toilet.