I'm fitting a thermostatic shower and i'm debating whether to use a female push fit elbow or a female compression elbow on speedfit pipe for the hot and cold supplies coming out of the wall into which the s-union fittings fits. Presumably it doesnt make any difference or is one more reliable that the other? i understand that standard pipe inserts should be used on the plastic and that if using compression that copper olives are preferable. Is this right?

Hi RWH,

You are correct on the last two - copper olives and inserts should be used on plastic!

As for the above, if it's the same thing I've just done recently, I ended up doing the shower run in copper - push fit and compression fittings were almost 1/3 or so longer than their solder guzzling cousins which meant I had to build the wall out to accomodate (small bathroom) or cut into the brick to sink the fitting (single course into another room, so not going to happen).

Might be worth checking - if needed, I can do a picture, but won't be till later in the week!

BG