On Tue, 18 Aug 2020 13:31:50 +0100, Andrew
wrote:


Your plumber should be aware of the move from black plastic
to blue plastic pipework for water supply, because it
occurred a long time ago. The black stuff was commonly used in
the 1970's but does split with age under certain conditions.

Inside a block of flats, I'm rather surprised that there
weren't 22 mm copper risers to each flat from ground level.
Were they built this way originally, or was the black plastic
piping a retrofit ?.

Thanks for the helpful explanation.
I don't know what was there originally. I just know that so many
compression joints coupled with stretches of dissimilar pipework has
so far been a recipe for expensive damage and shows every sign of
continuing to be so.
--

Mike