Swap main switch for RCBO for loft

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Hi,

In 2016 we had our loft converted and have 2 rooms and a bathroom up there. In total we have 9 double sockets, 4 spot lights, 1 shaving socket and 2 pendants lights. The ground and first floor were renovated in 2013 and had new electrics put in then also.

As the existing consumer board was full, a separate loft board was installed - see attached photos. All work was done by a qualified electrician and signed off.

Loft Board.jpg Main Board 1.jpg

Now I have asked a local electrician to add 2 additional double sockets to our loft rooms and having sent him photos of our consumer boards, says I need to swap out the "Main Switch" on the loft board with an RCBO: https://www.tlc-direct.co.uk/Products/MK6836S.html He says that as the loft board isn't protected by an RCBO it will need one.

Is this correct? I wasn't expecting anything additional to be needed given that everything was newly installed only a few years ago.

Thanks in advance.
 
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It looks like that board has RCD protection from the main board - can you confirm that circuit feeding is fed from one of the two RCDs? Have you got the original test results from the loft installation?
 
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Regs change and RCD protection is now required on all circuits. Can’t remember when this change occurred.
 
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says I need to swap out the "Main Switch" on the loft board with an RCBO: https://www.tlc-direct.co.uk/Products/MK6836S.html He says that as the loft board isn't protected by an RCBO it will need one.
Is this correct?
Not exactly; you might have misunderstood.
You cannot swap a main switch for an RCBO (well, you can but that would require a double-pole RCBO which is unusual in such situations and unlikely).

If the loft is not protected by an RCD in the main consumer unit, it would be better to swap the MCBs for RCBOs (or just the socket circuit) - not the main switch.
The main switch could be swapped for an RCCB but this would mean both circuits would be lost by one fault on either - as will be the case if the loft is protected by one of the RCCBs in the main CU.
 
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It looks like that board has RCD protection from the main board - can you confirm that circuit feeding is fed from one of the two RCDs? Have you got the original test results from the loft installation?

I'm afraid I can't - but the loft board will be fed from the main board.

Not exactly; you might have misunderstood.
You cannot swap a main switch for an RCBO (well, you can but that would require a double-pole RCBO which is unusual in such situations and unlikely).
Quoting the electrician directly: "the RCBO will just replace the existing trip switch for the loft sockets" as I said there is no space on either board for anything else.
 
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Although, as also said, not necessary IF the loft is protected by one of the RCCBs in the main CU.

Do you have the certificates from when the new CUs were fitted?
 
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Ah - if you turn off this switch, does it cut the supply to the loft?

upload_2021-11-2_16-32-0.png


If it does, then no alteration to loft CU is required.
 
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From your rather blurry picture, your main board has an RCD-protected MCB marked “DB2”
Turn this off snd see if the loft lights and sockets go off. If so then the loft consumer unit IS protected by an RCD and no change is needed upstairs. If this checks out then perhaps it is your electrician that needs to be changed!
 
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Do you have the certificates from when the new CUs were fitted?
I do somewhere but will have to dig them out. I've just checked now on the NICEIC website: http://www.checkmynotification.com/ and can see the two pieces of work listed so I'm confident they were done to regs.

Ah - if you turn off this switch, does it cut the supply to the loft?

View attachment 249336

If it does, then no alteration to loft CU is required.

Let me try that later tonight as the computer I'm on is in the loft. I'll report back later/tomorrow but what you're saying makes sense.

From your rather blurry picture, your main board has an RCD-protected MCB marked “DB2”
Turn this off snd see if the loft lights and sockets go off. If so then the loft consumer unit IS protected by an RCD and no change is needed upstairs. If this checks out then perhaps it is your electrician that needs to be changed!
Apolgoies for the blurry picture - I've uploaded a better one on my original post for future reference.

To be fair to the electrician I sent him the same photo so he is going on the same information you have. He's a local recommendation by lots of people so believe he is reputable, but always good to double check, hence why I'm posting here.
 
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Yep, as predicted the "DB2" switch on the main board kills everything in the loft.

So there's no need to swap a loft switch for an RCBO.

Thanks for all the help!
 
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Regs change and RCD protection is now required on all circuits. Can’t remember when this change occurred.
RCD protection is NOT required on all circuits, so the answer as to when this change occurred is never/not yet.
 
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RCD protection is NOT required on all circuits, so the answer as to when this change occurred is never/not yet.
Seem to remember 2008 the rules changed on bonding in bathrooms, so as far as most people are concerned the rules changed in 2008, at the point when @winston1 pointed this out it was a valid comment, although we now know it is RCD protected.
 
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