steam shower cabins and most non-steam showers, require an electrical supply feed.
In general, the shower units already comes with a 13 amp plug and an RCD [Residual Current Device] fitted. If you wish, this can be plugged directly into a mains socket OUTSIDE of the room where the shower unit is being installed.
We do however recommend, that you remove the plug and instead, have the shower connected directly to a fused spur socket inside the room. Should an RCD be already fitted to your electrical mains board, you can run a cable and connect direct to the existing RCD. If this is done, the RCD pre-fitted to the unit lead, can be removed too.
Note: All electrical work in the home MUST by law, be carried out by a qualified electrician.