Metal clad consumer unit.

[RF Lighting]

Hypothetical scenario:

Customer would like a new socket circuit and cooker circuit installed in their new extension.

They currently have a plastic consumer unit with sufficient spare ways and RCD protection for the additional circuits.

Does the consumer unit need to be replaced woth a metal unit for the new circuits to be fully compliant with BS7671?

 

[davelx]

The CU isn't a circuit; the circuit isn't a CU - so I can't see that the material the CU is made of can have any bearing on the compliance of the new circuit with the regs. 421.1.201 says nothing about circuits. I can't find anywhere in the regs that says anything like "Circuits must originate from a CU that complies with section 421.1.201".

 

[JohnW2]

Does the consumer unit need to be replaced woth a metal unit for the new circuits to be fully compliant with BS7671?

I'm inclined to agree with davelx and say 'no'. Furthermore, if the answer were otherwise, doing virtually anything in a CU would invoke the need for it to be 'non-combustible'.

Kind Regards, John

 

[chivers67]

I'd install a new cicuit no problem and note it down on any certification.

 

[EFLImpudence]

No, of course not. I am surprised that you need to ask.

If it were it would mean either -

that a new CU would be compulsory for any new electrical work in the premises, or

no new electrical work in the premises would be allowed without having a new CU.

 

[Lectrician]

The NICEIC suggest that if the consumer unit is not on an escape route, nor under wooden stairs with no fire barrier, and the CU shows no sign of overheating, you can add to it. Otherwise, no, you shouldn’t.

That’s their suggestion.

 

[JohnW2]

The NICEIC suggest that if the consumer unit is not on an escape route, nor under wooden stairs with no fire barrier, and the CU shows no sign of overheating, you can add to it. Otherwise, no, you shouldn’t. That’s their suggestion.

... but they are surely just 'making up' rules of their own?

The question being asked is about the interpretation of the regulation - i.e. whether the intention of the regulation is that a CU must be changed to metal if a new circuit is added to it. If the answer to that were 'yes', it would always be yes, even if the CU satisfied NICIEC's 'conditions' for the CU upgrade not being necessary. Conversely, if the answer were 'no', it would be 'no' even in an escape route or under the stairs - again despite NICIEC's view.

... I don't include "if the CU shows signs of overheating", since that one seems daft. If such signs exist, surely something needs to be done about it, regardless of the addition of a new circuit?

Kind Regards, John

 

[Lectrician]

I believe it is taken from an IETs best practice guide.

 

[JohnW2]

I believe it is taken from an IETs best practice guide.

Interesting.

If that's true, does it mean that the IET's intended interpretation of one of its own regulation is "It depends"?

Kind Regards, John

 

[EFLImpudence]

It's difficult not to despair, isn't it?

 

[ban-all-sheds]

Does the consumer unit need to be replaced woth a metal unit for the new circuits to be fully compliant with BS7671?

The following efficiently condenses the 9 posts between yours and this one.

No.