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zeeman26

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Hi guys

I am a newbie here and I am just a D.I.Yer so by no means an expert.

I have just put in a new bathroom and wanted to make some alterations to the wiring. There is a unswitched fuse inside the bathroom which is operated by a switched fuse outside the bathroom, I assume this was used for an electric towel rail/heater at one point. I would like to leave this in case one is installed in the future, I am replacing all the switches etc and wondered if I need the switch outside the bathroom to be fused or can it be a normal switch with the unswitched fuse in the bathroom? Also I have had a look at my fuse box and they are all MCB's. 6amp for lighting and 32amp for sockets. As far as I am aware all bathroom wiring should be RCD protected now? Would i need to change the fuse box or is there another way to satisfy the regulations?

Any more info required please let me know and thanks in advance.
 
you could fit a RCD fused sput unit to feed the bathroom circuit. if more than 1 circuit, you'd need a RCD FCU for each circuit.
 
Having a switched fuse (presumably FCU) feeding an unswitched fuse is odd but might have evolved from some past arrangement to have a connection point for a heated rail, etc. It might have been a way around the typical 10A limit & singe pole nature of a typical light switch, but you can get DP isolator switches in most accessory ranges rated at 20A which would do the job.

You are right that today both the lights and (more importantly) socket outlets and similar items should be RCD protected. As telectrix had just said you can get RCD versions of a FCU, though they should really be outside of the bathroom, as one means of achieving that. As you have one already for the heater rail, it is a simple change (but not as neat looking as an isolator switch that matches the lights, etc).

For the lights though you could do the same with another FCU outside the bathroom, but you would generally be better to protect the whole circuit. If you have two circuits and upstairs / downstairs switching that has been badly implemented with a "borrowed neutral" that will bring trouble to sort out.

Your best and longer-term option is to consider a new CU (consumer unit = fuse box, now they don't have actual fuses in them) that has RCD protection and ideally go for one that is all RCBOs as then any faults are clearly identified to the circuit responsible (where as a trip on a RCD feeding 4-6 MCB could be any of those circuits). That is not a DIY project by any means, though in Scotland you don't have the Part P notifications to worry about, you would still need to get a professional in to do that.
 
Keep the switched fuse spur and change the unswitched fused spur for a flex outlet plate.

Both are allowed in the bathroom in the correct places, but I just think it's always better to have the minimum parts that could get damp or corrode inside the bathroom. I hope that makes sense.
 
The suggestion by davesparks is very good and might explain the original reason for the 2nd fused outlet: the had one already and did not go looking for a 20A or similar flex outlet plate.
 
When you make any changes to a property, then the whole thing needs to be done to the latest building regulations, so for example if you have an old toilet/bathroom without a fan, that is ok, the regulations are not retrospective, if however you re-do that room, then it must be done to the latest standards (there are some limits, just adding a lick of paint doesn't mean you have to move to the latest standards) if that means a fan is required, then it must be added (just an example - probably not the case for your situation).

So if you have re-vamped the room, everything must be to the latest building regulations - fortunately in Scotland, you can view this online and download for free.
(the idea is if you want people to comply, you make the information available)

This could include the electrical systems associated with this room!
Typically a bathroom would require 30mA rcd protection on every circuit in that room, plus supplementary bonding of all the circuit earths to each other (and pipework), and slightly different protection classes for fittings.

(there are measurements that can be made which may allow omission of the bonding)

You need to check the regulations as if it's an adjoining wall, or in a tenement then different rules apply.

As for alternatives, the best would be a new consumer unit (cu) - better for the whole property for the future. Alternatively you may be able to replace the circuit's mcbs with rcbos (if available for the make/model of the existing cu). Or you could change the fcu for a rcd unit, plus add another rcd for the lighting circuit etc. (i.e. local rcds for each and all the bathroom circuits.),
 
Hi Guys

Appreciate all the replies and feedback on my original post. This has cleared up a few things for me and giving me a few various options. I am doing the property up at the moment and intend to sell next year sometime. However I do not want to put my own family or anyone else in future at risk. I have been in touch with Hager (my CU manufacturer) to see if they have RCBO's that can replace my current MCB's for that circuit. I have looked into a complete new unit but due to the fact I am selling I want to make it safe but at the most reasonable cost. If I cannot replace the current MCB's then I will look at a new unit and I will be getting a professional in to do this of course.

A quick one, if I can replace the current MCB's with RCBO's are there any other circuits that should be covered by this except the bathroom and any outdoor wiring?

Thanks again guys ?
 
A quick one, if I can replace the current MCB's with RCBO's are there any other circuits that should be covered by this except the bathroom and any outdoor wiring?
My list would be:
  1. Outdoor is highest risk - people cut cables with disturbing regularity, water also likely.
  2. Bathroom - due to presence of water, more so for things you can touch like heaters (lights unlikely to be in contact with)
  3. General 13A sockets, more chance of flaky equipment with damaged flex being plugged in.
  4. Otherwise any circuit where the cables run within 50mm of surface are now included due to risk of nailing one during DIY (not always discovering at the time)
If you can RCBO all circuits great, usual issue (beyond availability of compatible devices) is the neutral cables not reaching the RCBO as they were cut too short to only just make the common neutral bar.
 
If you’re in Scotland you will also need to check to see if you a Building Warrant. If you’re selling, my experience is that lawyers up here are hot on checking all relevant documents are in place for the transaction.

said lawyers will want to see the EIC/minor works etc (as relevant) together with test results and I would expect your electrical qualifications if you aren’t registered.
 
Thanks for that reply. Definitely a few options for me to look at so i appreciate everyone's feedback plus I have learnt a bit from this conversation.

So I have established that I need to at least RCBO the bathroom lighting circuit and the circuit that the towel rail FCU is on at very minimum (or add RCD protection to the MCB).

Other mods I am looking to make is install 4 x LED down lights (specific for the Zone they are in) instead of the original ceiling light. Also I want to replace the extractor fan/light with one on a timer and add a mirror with light and shaver socket. I have all these bought and ready to start the installation.

At present one switch operates the ceiling light and extractor fan/light and another switch operates another extractor fan. There is also the 2 switched FCU's that operate the socket and the FCU for the towel rail.

My plan is to take away the feed for the socket, hoping this is just a spur as the socket is under the bath and therefore not safe in my opinion. The FCU for the towel rail has already been covered. The LED down lights I was just going to wire in loop as I want them all to operate from the same switch. The extractor/light I want to work off an independent switch, should this Fused? It will have an isolator outside the bathroom also. The mirror with shaver socket has a pull cord for the light and a switch for the shaver socket, when I wire this should I wire it through a FCU?

Sorry if any of that isn't clear. Trying to get peoples opinions so I do it to the correct regs and the best way. Thanks
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If you’re in Scotland you will also need to check to see if you a Building Warrant. If you’re selling, my experience is that lawyers up here are hot on checking all relevant documents are in place for the transaction.

said lawyers will want to see the EIC/minor works etc (as relevant) together with test results and I would expect your electrical qualifications if you aren’t registered.

I am looking into this just now and will ask the question. So far from what Im reading a building warrant would not be required. Yes a can see there will be a good chance I will require the work checked and signed off by a professional which may be difficult. However I do know a couple of registered electricians that could do it.
 
The only person that can sign a certificate is the person completing the work. It is a self certification scheme we operate in Scotland. A 'friend' signing a certificate for you is in breach of BS7671 and if they are registered would be open to criticism/action by their registering body. Essentially they are lying - signing to sy they did the work when they didn't. Just sounds to me that you are trying to do things on the cheap and avoid what is required of you. Good luck.
 
The only person that can sign a certificate is the person completing the work. It is a self certification scheme we operate in Scotland. A 'friend' signing a certificate for you is in breach of BS7671 and if they are registered would be open to criticism/action by their registering body. Essentially they are lying - signing to sy they did the work when they didn't. Just sounds to me that you are trying to do things on the cheap and avoid what is required of you. Good luck.

That is not the case at all. I will gladly sign my own work and would not ask someone to say they did the installation for me, as if anyone would do that for anyone. I misunderstood your original message and thought what you were saying is it may need to be checked by someone in which case I said I could have someone check the work not sign it off as their own.

As I have said previously the change in the CU I will not attempt myself as I am not qualified or experienced enough with that. But to pay someone to wire in a replacement fan with a slight difference, 4 LED lights and a mirror light/socket to me seems a waste of money.
 

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