En-Suite / Wetroom wiring

Hello all,

I am looking for advice on my new en-suite wiring first fix.

I am having UFH @ 150W, LED/DeMist/Shaver Bathroom mirror and an inline extractor fan with humidistat.

I am not 100% on wiring best practice, my thoughts are...

Consumer Unit (directly below en-suite) does not have an RCD MCB but does have capacity to add one, i have however recently ran 2.5 from the CU, under the bathroom floor to my boiler in the upstairs utility room, so what i plan to do....

Take a feed from the 2.5 to my boiler into my en suite airing cupboard where it will terminate to a double pole rcd spur.
https://www.screwfix.com/p/powerbreaker-13a-30ma-double-pole-passive-rcd-connection-unit/40097
from here a feed to my humidistat then to my fan
another feed from the RCD to the UFH Stat and then onto my bathroom mirror.

this will allow me to isolate the entire bathroom and provide double pole protection.

how wrong am i!?

PS, once i have ran the first fix a qualified spark will commission before i get the "if you dont know pay someone to come and do it" responses that seem to be common these days .

thanks in advance.

sh4d0w said:

I am looking for advice on my new en-suite wiring first fix. .... PS, once i have ran the first fix a qualified spark will commission before i get the "if you dont know pay someone to come and do it" responses that seem to be common these days .

Click to expand...

You're still likely to get unwelcome responses, since that's not really how it works. If this ensuite contains a bath or shower (which I presume it would), then you're definitely talking about notifiable work (and there are presumably 'new circuits' involved, which would be notifiable in any room, anyway) - and the requirement is that the electrician doing the certification and notifying declares that he/she has "designed, constructed and tested" all of the work.

You therefore need to get an electrician on board prior to the 'first fix', since they may not be happy with the design you have arrived at as a result of asking people on an internet forum and, in any event, theoretically should 'supervise' the first fix (particularly if any of the cables will not subsequently be visible for their entire length). Having agreed what should be done, the electrician would also be able to indicate what parts (if any) of the work they would be happy for you to do (and still certify it 'as their own work').

Kind Regards, John

thank you John, i hear you and appreciate your response and explanation.

For the hypothetical peace of mind... are my chain of thoughts correct?

sh4d0w said:

thank you John, i hear you and appreciate your response and explanation. .... For the hypothetical peace of mind... are my chain of thoughts correct?

Click to expand...

Well, it sounds like one way to do it but, as I implied before, there can be no guarantee that the electrician would be happy to do it like that (or in any other particular way you might think of).

Do I take it that the cable you mention feeds only the boiler (and, if so, is that via an FCU?)? What is the rating of the MCB protecting the cable? Is your UFH really 150W total, rather than 150W/m²?

Kind Regards, John

You are correct with your assumption, UFH is 150peak per M2, i have only 2.5 Mts so 375W, towel rail was missed off here at 400W peak (if i ever use the electric element)

My (and i known many others) mains feed to the Fan and to the heated mirror come from the Light Circuit.
SFK

the cable does only feed my boiler, Vaillant ecoTEC Plus 624, so its really only powering the pump at a max load of 70W

SFK said:

My (and i known many others) mains feed to the Fan and to the heated mirror come from the Light Circuit.
SFK

Click to expand...

this was my plan, and how easy that would be, plus i dont think that would be notifiable work either, however... that circuit is not on an RCD so if i did this id need to chance my MCB to an RCBO i suspect