I have a leak at the join between the plastic soil pipe running vertically
down from the bathroom and the clay soil pipe sticking vertically out of the
ground. They are connected by a HepSleve plastic connector.

On inspection (throught rodding eye) the plastic soil pipe stops 10mm short
of (i.e. it doesn't fit into) the clay pipe, as I would have expected.
Therefore the join is relying on the seal between the OD of the pipes and
the ID of the plastic joining sleeve that both pipes fit into. The leak is
between the clay pipe OD and the joining sleeve ID.

Is this normal, or should the plastic pipe go slightly into the clay pipe?

If so, unfortunatly, dropping/replacing with a longer plastic pipe is not
really an option. Major distruction to bathroom tiles would be required.

Any ideas?

Many thanks,

Darren