Set Square wrote:
In an earlier contribution to this discussion,
Andrew Gabriel wrote:

. Might want to
keep the length of run to the 110mm soil stack as short as possible,
particulary the outdoor part of it. Condensate is still slightly
warm on mine when it runs into the pipe, so it would probably be
quite difficult to get it to freeze inside the loft area.

I think it's an *internal* soil stack - so there wouldn't be an outdoor
part.

Indeed it is, and the walls are 50cm stone, so it's very unlikely to freeze
in sharp snaps.
Thanks all.
Now, the question remains - will the plumber consent to installing it this
way (it's being done free under the auspices of EAGA)