I want to fit an electrically heated towel rail in the bathroom close to the bath and the shower. Is it ok to pass the cable through a cable outlet plate and join it to the supply in the wall which will be a fused spur of the ring main?
It is difficult to answer questions about bathrooms the location is very important. There were 4 zones soon to become 3 zones so starting with easiest. If 3.5 meters from bath or shower and protected by an RCD you could even plug it directly into a socket. But you would need a big bathroom for that. New rules require an RCD even for lights although you can still use old rules until 1st July which further complicates things as one can't mix and match. 701.55 (v) Towel rails allowed in Zone 1. But no switch allowed even in zone 2 and any spur unit must be to IPX4 (701.512.3 and 701.512.2) and RCD protection 701.411.3.3 required I am going to new regulations here as I don't have old book to hand.
So looking at your question the cable outlet plate must be for bathroom use and one would normally place the fused spur outside the bathroom. And if you include this on the plan submitted to building controls it will most likely cost you more for their fees than using a registered electrician to do whole job. Also the plan will need to be far more detailed than what you have given here and it will need a drawing to show exactly where each item is being fitted and also most likely a copy of your qualifications in order to be able to design and install and if your testing yourself also inspection and testing qualifications plus copies of calibration certs for the meters you use. Yes you can DIY under Part P but they put up every barrier to persuade you not to. For such a small job not really worth the hassle. Remember you as house holder are responsible for Part P if you do get an electrician to do the job for you do make sure he can issue building controls completion cert as well as the electrical paperwork. If you want to know more about Part P there are links in projects section.
With it being a special location near enough is not good enough as it will be inspected and you do really need to read regulations yourself.
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