andrewpreece wrote:
Well, as in the previous thread of the same name I have now smashed open
the concrete surrounding the joint between the cast iron soil downpipe and
the saltglaze sewer pipe where I fancied I had a leak and found a cavity
about a cubic foot in size and a badly cracked 135 degree salt-glazed pipe
which connects into the rainwater drain from the gully, via a teeing-in
pipe.

The teeing-in pipe has cracked flanges too, though it doesn't visibly drip
water like the
cracked soil pipe connection: that lost half a cup of water each time I
flushed the loo.

Questions:_

Is it best to replace like with like, or can I use plastic sewer pipe?

Plastic is fine, you'll need connectors, though, and the pipe should
be encased in concrete.


Do I have to take up two sections of sewer pipe at the same time, in order
to be able to fit them together?

Depends on your connectors...


Is it easy to separate salt-glazed sewer pipes that have been cemented
together at the join without running the risk of fracturing the good pipe?

No, it's difficult. You *might* be able to do it by
stitch-drilling into the mortar in the socket, but
you're likely to break the socket anyway.


If there are hairline cracks on glazed pipes, can I just coat them with
something
( I dunno, like bitumen ) an bury them back in concrete?

Replace or encase in concrete.