"Dave" wrote in message
...
I need to run concealed pipes from beneath the floor to wall-bracket
compression elbows for a wall mounted shower mixer, but can't decide the
best way to do it.
I'll need to cut a duct in the blockwork, is it best to mortar-in the
pipes or to use exterior ply over the duct (there'll be tiles over the
top)?

Either option ok

Is it best to use copper or barrier pipe? I'd be worried about the mortar
attacking the copper but presumably the plastic barrier pipe doesn't need
protecting(?)

Again both ok

Are there any problems using regular compression fittings on barrier pipe?

Provided that you use pipe inserts no problem

--
Dave S
(The return email address is a dummy)