Now stripping out plumbing and electrics.

Is it a hanging offence to use a 15mm compression stop end on a gas
pipe?

There is no provision for locking the supply shut off valve in the
outdoor meter cabinet. The 15mm is T'd off from the boiler feed and runs
across ceiling joists which are coming out.

Also Megaflow experience.. There is ample mains pressure here 4-6 bar so
the system can run at the designed pressure. I am considering pipe
routing (to minimise hot water arrival times) and wonder if 15mm gives
adequate bath fill flow rates.

Also any thoughts about plastic piping for plumbing other than
underfloor heating? Noise, reliability for hot supply etc.
--
Tim Lamb