Shower valve

[Tel77]

I'm in the process of replacing the shower and need to rip out the old shower valve. The trouble is I don's seem to be able to find any isoloator valvers for the shower or sink taps unless they're buried in the wall.

The trouble is the system is a pressurised un-vented system which have no experience with. Is there a simple way of isolating the water?

 

[muggles]

Just turn off your stopcock to isolate both the hot and cold. It'll take a little while for the hot to depressurise, just be patient with it

 

[Tel77]

I suspected that may do the job but wondered about the best way to seal the pipes off while I prepare the rest of the bathroom as I will still need running water in the rest of the house.

Are normal isolating valves suitable as a method of isolating these pipes?
Most of the pipes in the house are plastic so wondered if using normal isolating valves would be able to cope with the pressure?

 

[muggles]

If it's for a shower I'd generally recommend full-bore isolation valves but 'normal' ones will be fine assuming you're talking about the standard quarter-turn ballofix valves, gate valves are not suitable as they're for low-pressure systems only. You'll need to identify what make of plastic pipe you have and obtain the correct inserts for it or the fitting may blow off fairly quickly. It's best, if you can, to put them somewhere accessible such as the loft.

 

[Tel77]

Thanks for the advice so far.
I'm puzzled why there doesn't seem to be any isolation valves already installed(at least visibly anyway) so I guess I'll have to shut the system down while I install some.