2 consumer units..

27 Jan 2004
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United Kingdom
Currently building an extension and just about at the first fix electrics stage, a new CU will go in the extension and will eventually be the main CU, I have spoken to the supplier about a supply and meter move, they have no probs with that.

So my question is,would it feasible to supply the new CU from the existing CU using 16mm swa?

Loadings would be lights and sockets (washing machine, kettle etc no cookers or showers at present).

Not looking to relocate the meter etc until next year as I have enough on my plate at present without digging up the garden/drive etc for the DNO.

Thanks all
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If you feed the new CU from the old CU using 16mm SWA, then when you come to move the meter you could swap it about and feed the old CU from the new... You might have to use 25mm SWA due to volt drop & EFLI issues

Just remember to gland it properly!
Should of said, the old CU will be coming away and the existing circuits re routed into the new CU.

Ref glanding, quite often work with the leccy at work (I'm a maint mech engineer) so done it often enough under his supervision, but I'll more than likely be getting an electrician in to do the electrics on the extension.

Just knocking some ideas around..
To legally do what you propose you will need to inform the LABC and pay their fees up front.

There is nothing wrong with what you want to do but much depends on the status of person doing the work.

Anyone who is registered under Part P will have no problems but if you need to use the LABC route then there may be time limits etc.

You talk about using an electrician I would then say leave the linguistics up to him to sort out as if he is signing the paper work it is his call and what he says goes.
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What if anything did your application for building regs (you do have one for the extention right?) approval say about the electrics.
surely if he's having an extension built then there have been plans submitted and notifications made..
Precisely - and in the submission there will be pages of detail describing how all of the applicable BR requirements will be met.

One of those requirements is P1.

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