On 20/01/2020 13:01, rick wrote:
If you are fitting a freestanding shower, should you fit isolation valve
to H&C feed valves?

AIUI:

/isolation/ (or "service") valves are optional - but IMHO /should/ be
fitted as they let you service the shower without turning off the water
to other places. Of course this assumes the valve works - without
leaking - when you come to want to use it. That ain't always true for
the valves in cheap flexible tap connectors. And as already mentioned,
full bore valves offer maximum flow rates.

/check/ valves to stop backflow into the water supply are required by
the regs in some cases and then /must/ be fitted. With a shower that's
mainly where the shower head could be submerged or where there's a mixer
tap with unbalanced supplies. But note that some mixer taps have them
built in.

--
Robin
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