On 04/07/2012 13:26, James wrote:
On 2012-07-03 21:16:27 +0000, newshound said:

Looks a bit like an iron waste pipe to me; don't recognise the collar
at all. What happens outside? One option might be to fit a new plastic
pipe through the wall to an existing iron stack outside (which is what
I have). Then you can have nice modern unbodged pipework inside the
house.

Thanks for the reply. I've just posted links to another couple of
pictures of the outside -- see my reply to Adam.

Your idea sounds promising, if I can get the old joint apart on the
other side of the wall without damaging it. How did you fit the new
plastic pipe into the old joint?

In my case, I only replaced the vertical "vent" pipe (previous owner had
replaced the angled one carrying fluid). As I recall, once I had removed
all the old iron (a bit fiddly as you don't want to crack the junction)
the new pipe "bottomed" on a step in the collar, which makes it fairly
easy. Pack the bottom part of the joint with something like newspaper,
string, baler twine, rope, etc and create a seal using suitable mastic
or silicone. You can finish off the top with silicone, mastic, or even a
cement filet. Since it never really sees positive pressure (even if
there is stuff flowing down) the seal does not have to be brilliant.