Wingedcat wrote:
I would certainly answer your second question before worrying about
your first - that is, what sort of shower you are going to end up with,
as each have different (and v. specific) requirements regarding the
type of water supply. For instance you certainly could not connect
mains cold water to a pumped shower.

thanks. I'm going for thermostatic mixer from G fed water, no pump.

Regarding the pipe cutting dilemma, if you are joining copper to copper
with soldered fittings I would have no hesitation in using a hacksaw or
other primitave cutting device, anything that doesn't distort the
roundness of the pipe basically. (Make sure you wash out swarf first
though before connecting to your new shower).

(Sits back and awaits furious admonishings...)

If you've got plastic pipe or are going to be using push-on fittings, I
would recommend the use of a proper pipe cutter, which will necessitate
(it seems) some rearranging (or further disconnecting downstream
perhaps?) of the pipes. Often if you make one cut further back in a
pipe run, the pipe will flex giving you plenty of room to get a pipe
cutter to it.

Plastic would be more convenient as i need to make a few turns (2X90
degree) , but can it attach directly to the shower unit? Reading
through posts here tho, many people seem to think copper is the "right"
way and it will make cutting easier if i can get away with a hacksaw.
The pipe cutting is to put T pieces in so I guess they'll be copper
anyway. To give enough space to fit the pipes together, the chases in
the wall will have to be pretty deep though which seems an advantage of
plastic's flexibility.