New Consumer Unit ?

[billm]

My house was rewired about 10 years ago by an Electrical firm and I was given a Certificate that the job was completed to standards. He fitted an 8 way single RCD Consumer Unit with a plastic casing.

I am in the process of building an extension onto the kitchen and have completed the 1st fix wiring of the new sockets & lights, all done under a Building Control Notice. None of my wiring impacts or changes the wiring in the Consumer Unit.

Today I had an Electrician visit to quote for signing off the electrics and he is happy with everything but he said the Consumer Unit needs replacing with a metal cased twin RCD as the current Specs were changed a few months ago.

I know metal cased Consumer Units have to be fitted for new builds but I thought there might be an exemption for extensions added onto houses where a Certificate already exists for the existing installation.

Do I have to replace my Consumer unit to a twin RCD metal one to obtain a sign off ?

 

[EFLImpudence]

No.

 

[Risteard]

No.

I think the correct answer is that he does if the Electrician will not sign it off otherwise.

 

[PBC_1966]

Get a different electrician. He should know that the new rule doesn't apply to something which was already installed years before.

 

[Anteaus]

All circuits should now be RCD protected including lighting. AFAIK there is no specific requirement for split RCD protection. The metal case requirement only applies if the CU is replaced after 1 Jan 2016. If your lighting circuits are not RCD protected, then RCBOs might be an option.

 

[sparkwright]

All circuits should now be RCD protected including lighting.

Bit of a misleading generalisation, though I'd agree in most cases this would be correct.

 

[oldbutnotdead]

If you are extending ring finals and lighting circuits and everything in the new bit is protected by your (existing) single RCD then no there is no reason to have a new CU fitted.

Slight aside for you all- those single breaker enclosures you can fit (usually for a shower or maybe for an outbuilding)- are they covered by Amendment 3 as well? Just occured to me- if one wanted to (lets say) add an additional ring final but your existing (plastic) CU was full it'd be a lot cheaper and easier (though messy) to use Henley blocks and a 32A RCD in a single enclosure rather than replacing the whole CU. Just a thought.........

 

[EFLImpudence]

Slight aside for you all- those single breaker enclosures you can fit (usually for a shower or maybe for an outbuilding)- are they covered by Amendment 3 as well?

If they are "consumer units" or "similar switchgear assemblies".

Opinions differ. That's unusual isn't it?

 

[ban-all-sheds]

Building Control Notice.

In the name of all that is sensible, WOE did you do that rather than a full plans submission?

A BN saves you absolutely nothing in LABC charges, but opens you up to all sorts of risks of pretty arbitrary decisions by the BCO about what he likes, and about which you can do nothing, as you didn't get their agreement up-front about how you would be doing things.

Today I had an Electrician visit to quote for signing off the electrics

I don't know what "signing off" you think you'll get, but it won't be an EIC, and it won't be a Building Regulations compliance self-certification. Have you thought about what you will do if the council turn round and say "Nope - that won't do, no completion certificate unless you have it ripped out and re-done by a qualified electrician"?

 

[oldbutnotdead]

Hmm. Now to me (I'm playing a bit here), a consumer unit has a main double pole isolator and then an arrangement to permit multiple lower current circuits to be safely connected to the incoming supply. I'm not sure if a single breaker enclosure is similar enough- there's no provision for multiple lower current circuits and no distribution going on.

And in my theoretical scenario, a single RCD in a single metal box with Henley blocks (are they still permitted- don't really fancy metal clad version of them unless the enclosure is well separated from the tails) will still be way cheaper than a whole new CU.

(I'll add again I'm playing here- how would my scheme above play with any scheme-registered electrician who was asked to install such a setup)

 

[ban-all-sheds]

Hmm. Now to me (I'm playing a bit here), a consumer unit has a main double pole isolator and then an arrangement to permit multiple lower current circuits to be safely connected to the incoming supply. I'm not sure if a single breaker enclosure is similar enough- there's no provision for multiple lower current circuits and no distribution going on.

(I'll add again I'm playing here- how would my scheme above play with any scheme-registered electrician who was asked to install such a setup)

Well - I guess EFLI is right about opinions differing, but personally I would seriously question the intelligence and/or rationality of an electrician who really thought that an enclosure with an RCD/MCB/RCBO in it was not a "similar switchgear assembly".

 

[EFLImpudence]

Hmm. Now to me (I'm playing a bit here)

So am I

a consumer unit has a main double pole isolator and then an arrangement to permit multiple lower current circuits to be safely connected to the incoming supply. I'm not sure if a single breaker enclosure is similar enough- there's no provision for multiple lower current circuits and no distribution going on.

The definition of CU states "one or more fuses, MCBs etc".

(I'll add again I'm playing here- how would my scheme above play with any scheme-registered electrician who was asked to install such a setup)

They won't know either so they will make up something.

 

[EFLImpudence]

Well - I guess EFLI is right about opinions differing, but personally I would seriously question the intelligence and/or rationality of an electrician who really thought that an enclosure with an RCD/MCB/RCBO in it was not a "similar switchgear assembly".

So would I but I have read many arguing the case - not here.

The point about one or more is obvious isn't it?
Otherwise it would lead to Shower CUs - they are called CUs - not being subject to the requirement and Garage CUs, with two, being subject.

 

[ban-all-sheds]

It does not seem to me either intelligent or rational to think that if it had only one device then it would not be a "similar" switchgear assembly.

 

[oldbutnotdead]

And given that definition of CU then I have to agree with the two of you. Ho hum....... still might be an economic (but untidy) option for those needing to expand their distribution facilities by 1 or 2 slots. Ta all