fitting a n electric shower

[PLATER1950]

do i need 10mm cable for my 9.5/shower

[Ethel]

For showers rated above 8kW a minimum cable size of 10mm2 is strongly recommended

You can use this guide:

http://www.tlc-direct.co.uk/Technical/Charts/V oltageDrop.html

[woodchopper]

Make sure your pull cord switch for it if used is rated at 50amps as well

[terence7556]

what matters is the distance from the consumer unit to the shower and the voltage drop along the cable. if the distance is short enough , quite easy in modern apartments but not in houses ,for the lower rated showers (7.5kw )then 6mm might do, but not for 9.5kw
the reality of it is that 10mm costs more but when ,not if your shower fails and you wish to replace it with one that is more powerful than 9.5kw you will save a lot of work by having used 10mm in the first instance