I have an electric shower in the bathroom which is no longer used. I wish to install a new shower in another room but want to utilise the 6mm cable that serves the original shower unit. The new shower is a 10kw unit and i want to know the best way to cut into the existing cable in the loft and spur off to the new shower. Should i abandon the old cable and do a straight through joint or could i use a connection box to join all three 'tails' in case we need to use the existing shower at some point again. We will NOT be using the showers at the same time. Your help would be appreciated, thanks.