Am looking for a bit of advice on some electrical work I am doing in my
bathroom. I am doing it mostly myself and am planning on putting in a
new electric shower and jacuzzi bath (1700*700, not hottub!).

I have upgraded the existing electric feed for the shower to 10mm twin
and earth because the shower I have bought is 10.8KW, and I will be
putting in an rcd in the electric cupboard.

I was also planning on hooking up the jacuzzi to this feed too. Due to
the rather large capacity of 10mm cable I was thinking of using an RCD
as low as maybe 5 amps?, which I was probably going to put in under
the bath itself (The rating of the jacuzzi is 4 amps).

At the electrical cupboard, assuming the voltage is 240 (or 230?) Thats
around 45 amps and with the jacuzzi thats around 49 amps , so i am
assuming I will have to use an rcd larger than 45 amps. I could make a
point of never using the two together but would prob rather it didn't
cut out if I did!

What is the next size above 45 amps (rcd rating) and does what I have
mentioned above all seem above board?

Any advice greatly appreciated

Miguel