Compression isolating valves and plastic pipe

[pertinky]

Is it preferable to use push fit isolating/service valves when using plastic or can normal brass fittings be used? Or is it better to switch to copper at the WC/basin/shower?

I have a little access hole where I'm planning on putting 4 valves for two showers on the off chance one of them needs to be isolated so I still have a working shower (fed by the same 22mm supply) but I can't seem to find any blurb on using normal compression fittings with something like speedfit.

My gut tells me no or with caution...but copper on to pushfit seems to be acceptable

 

[terryplumb]

You can use either push fit or compression isolators. Ensure pipe stiffeners are inserted into plastic pipes ,and full bore isolating valves will give better flow .

 

[pertinky]

You can use either push fit or compression isolators. Ensure pipe stiffeners are inserted into plastic pipes ,and full bore isolating valves will give better flow .

Ah good, I picked up a few full bore valves just incase as well the the *standard* inserts for the pipe (not the ones with the extra O ring that I use for normal connections)

 

[SandyLyon]

Make sure you use the pipe inserts, you will find that copper olivies work better as they are softer than the brass ones.
Also don’t be tempted to use any type of jointing paste, if needed you can add a few wraps of PTFE tape.
Don’t over tighten.