Hi, I currently have a 7.5 kw shower connected via a 6mm cable on a 32a MCB. I would like to have this uprated (before the cold weather comes) to a 9.5 or even 10.5 kw unit. Replacing the cable with a 10mm cable between the consumer unit and double pole switch shouldn't cause to many issues, however the cable run(approx 2m) from the switch to the shower is chased into the plaster and behind the tiles and would make a mess of what is currently a nicely decorated bathroom. My question is would it be acceptable to keep this section of cable as 6mm while replacing the main cable run (about 11-12m) with 10 mm cable along with fitting the appropriate MCB. I would be getting a qualified electrician in to do this but am looking for a heads up on what the options are. Thanks.