Help me figure out this bathroom wiring.

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James45623

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I'm renovating my bathroom and just wanting to move the extractor fan isolating switch over about a meter or so and also add a connection (fused spur) for a new electric towel radiator.

I've taken a picture of the wiring at the fan isolator switch and I can't workout why there's about 4 live wires going into the L1 terminal and only 2 into the L2 while there's 4 neutrals in the N. The bottom L1, L2 and N are going to the extractor fan, so that I understand. The only things we have in our bathroom are the main light, light switch, shaver socket and an extractor fan.

Can you shed light on what's powering what and if it's fine for me to take a feed from here to a fused spur for the electric towel radiator?

Becuase I need to move this a meter or so, I'm thinking of extending everything using wago's + a maintenance free wago box, would this be ok?
 

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The four are permanent live or the 'loop' the two on their own are switch returns. This is based on assumption of the fan connections (red, yellow and blue).
The works you are undertaking are notifiable to Building Control under Part P of the Building Regulations, that is a legal requirement.
 
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So someone used the fan isolator as a junction box.

Not sure I would tap a towel rad into the light circuit, unless it's low wattage, like 150w. You would need to assess total load on the circuit, which is 6amps max, although with led lights very few light circuits come anywhere near that these days.
 
The four are permanent live or the 'loop' the two on their own are switch returns. This is based on assumption of the fan connections (red, yellow and blue).
The works you are undertaking are notifiable to Building Control under Part P of the Building Regulations, that is a legal requirement.

So someone used the fan isolator as a junction box.

Not sure I would tap a towel rad into the light circuit, unless it's low wattage, like 150w. You would need to assess total load on the circuit, which is 6amps max, although with led lights very few light circuits come anywhere near that these days.

I see.

The lighting circuit isn't RCD protected either. Luckily, I've got a socket nearby which is RCD protected, so I'm thinking of wiring a fused spur off of it for the heated towel radiator.

It still leaves me with the issue of extending the cables at the fan isolator to a new location. Is it fine for me to simply 'wago' all the incoming wires at the fan isolater and then take a 2.5mm twin and earth to the switch at its new location?
 
The fan isolator is there to "break" the live, switched live and neutral to the fan. (For the purpose of isolating the fan)
If you are wanting to move it, you will need 2 x 3 core and earth. NOT just one 2.5mm Twin & Earth (It does not have enough cores)
One set of 3 would be going to the fan isolator.
The other set of 3 would be coming from the fan isolator
Not forgetting the earths.

More wagos, would be interesting (Not a lot of space left) Could you not go into the loft and pull the cables up?

With regard to the towel rad, you could just plug it in.
 
The fan isolator is there to "break" the live, switched live and neutral to the fan. (For the purpose of isolating the fan)
If you are wanting to move it, you will need 2 x 3 core and earth. NOT just one 2.5mm Twin & Earth (It does not have enough cores)
One set of 3 would be going to the fan isolator.
The other set of 3 would be coming from the fan isolator
Not forgetting the earths.

More wagos, would be interesting (Not a lot of space left) Could you not go into the loft and pull the cables up?

With regard to the towel rad, you could just plug it in.

Ah ok, that makes sense. Two 3 core and earth cables given that I need to extend each of the top and bottom L1, L2, N and earth connections, one set coming in and the other going out (to the fan).

I thought of going in the loft but it's been converted into a bedroom and those cables are right in the middle of it. Given chipboard floor, carpet and bed on top, it would be a nightmare trying to get at them. There is a void where the cables come down from the ceiling, so I'm hoping I can cut some of the plasterboard out, squeeze a wago box up there with a cable tie and call it a day.
 
Who is notifying this to Building Control undertaking these works without doing so is illegal.
 
Ah ok, that makes sense. Two 3 core and earth cables given that I need to extend each of the top and bottom L1, L2, N and earth connections, one set coming in and the other going out (to the fan).

I thought of going in the loft but it's been converted into a bedroom and those cables are right in the middle of it. Given chipboard floor, carpet and bed on top, it would be a nightmare trying to get at them. There is a void where the cables come down from the ceiling, so I'm hoping I can cut some of the plasterboard out, squeeze a wago box up there with a cable tie and call it a day.
Is it possible to move the connections to the void under the eaves in the attic? Burying cable connections is best avoided even if they are wagos.

One trick I use when faced with sheet material flooring like chipboard is to cut hole (s) with a 6" hole saw. Big enough hole to get your hands in, easily patched up with a bit of batten to support the cutout.
 
Ah ok, that makes sense. Two 3 core and earth cables given that I need to extend each of the top and bottom L1, L2, N and earth connections, one set coming in and the other going out (to the fan).

I thought of going in the loft but it's been converted into a bedroom and those cables are right in the middle of it. Given chipboard floor, carpet and bed on top, it would be a nightmare trying to get at them. There is a void where the cables come down from the ceiling, so I'm hoping I can cut some of the plasterboard out, squeeze a wago box up there with a cable tie and call it a day.

Not sure if your proposed solution would ensure all buried cables are run in "Safe-Zones"?

If you are doing redecoration work in the bath, is it possible to access the ceiling void cables by cutting an access hole in the plaster board ceiling rather than cutting floorboards?
 
Not sure if your proposed solution would ensure all buried cables are run in "Safe-Zones"?

If you are doing redecoration work in the bath, is it possible to access the ceiling void cables by cutting an access hole in the plaster board ceiling rather than cutting floorboards?

The isolator was originally above the bathroom door. The studwork and door has been completely ripped out but will be put back in the same place except above the door there will be a pane of glass to bring light into the corridor hence the need to move the isolator switch over to the right by about 80cm.

I've marked in orange where I believe the joists run across the room. That's the idea: cut out an access hole, pop cables into wago connectors and then all of it into a wago box. Technically, the cables won't be in 'safe zones' given that they need to be at least 50mm away from joists and the top and bottom of the plasterboard but I'll see what else can be done to make it relatively safe.
 

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The works you are undertaking are notifiable to Building Control under Part P of the Building Regulations, that is a legal requirement.
Notifiable yes, but nothing to do with part P which is just one sentence which basically says work must be done safely.
 
Are the cables long enough to just relocate the isolator into the ceiling either inside or outside the bathroom door?

Possibly, yes. I'll see if the cables would reach just inside the bathroom, near the light pullcord siwtch and perhaps put another pullcord beside it for the isolator?
 
Not to be that guy who asks for help and disappears without giving an update, I thought I'd say that I've completed the job. I used a colossal wago box to fit all the wires in and it's safely tucked away. I did consider coming at the wires form the top, but realised the hole in the bathroom is directly underneath the loft steel beam 😅

And excuse the mismatch of wago connectors, I had to make do with the few older ones I had left over.

I also managed to move the pullswitch cord along about meter or so too. Tested all the wires and connections before putting them into the wago box and closing it up.

Thanks all!
 

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We have an old consumer unit that only has a single RCD. I'll have to DIY fit a new duel RCD board later on to have the lighting circuit protected.

Just kidding; I'll have an electrician come round to upgrade our board very soon.
 
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