Adding another circuit to and old cu

Lexicon · Oct 16, 2024

I need another radial circuit adding to our cu board to supply a new shed / workshop. We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards, being installed in 1979. It does have rcd protection rated at 100ma.
Can a new circuit be connected under current legislation? or is a replacement CU mandatory?

Chewbacca · Oct 16, 2024

Can you post a picture of the old board.

ProDave · Oct 16, 2024

Lexicon said:
We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards, being installed in 1979. It does have rcd protection rated at 100ma.

So you spent many many £000's on buying a house including due dilligence and getting an eicr done, but have decided not so spend a few £00 getting the electrics upgraded, which you knew before you bought needed to be done?

Perhaps now is that time?

Murdoch · Oct 16, 2024

The radial might not need RCD protection at 30 mA

SPECIAL LOCATION · Oct 16, 2024

Lexicon said:
the cu was deemed unsatisfactory because in does not comply with current standards,

I can't quite figure out from your post if remedial work has been carried out to make the installation satisfactory for continued use following the EICR? (if not, why not?)

If it is still not satisfactory then I would not recommend adding any new circuits or extending any existing circuits..

Always keep in mind that electricity is invisible, difficult to hear or smell but it can kill a healthy adult in less than a second..
and I believe it is still used in some parts of America to administer the death penalty!!

And..
Electrical alterations/additions are NOT about making something work.. (which is the typical DIY consideration)..

Professionally designed electrical alterations/additions are about ENSURING that in the event of a fault the source(s) of energy will be disconnected fast enough before any people, property or livestock could be put into any danger!!

Murdoch · Oct 17, 2024

Lexicon said:
I need another radial circuit adding to our cu board to supply a new shed / workshop. We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards, being installed in 1979.

To be frank, if you've just bought a new house, spending around £1K is not even a drop in the ocean - so my advice to you IS upgrade the CU as any changes to the internal electrics of the house WILL require this.

UNG · Oct 17, 2024

It always surprise's me what value some people put on their own safety and that of others

Murdoch · Oct 17, 2024

UNG said:
It always surprise's me what value some people put on their own safety and that of others

Yup - spend their money on anything but what is important for home/ family safety

Andy™ · Oct 17, 2024

people would rather spend money on something they can show off like a new kitchen or bathroom, rather than spend a few £ on something that could save their life / stop the house burning down. the old one works so it must be safe...

SPECIAL LOCATION · Oct 17, 2024

Lexicon said:
We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards,

An EICR stating that an installation is unsatisfactory means there are one or more areas that are considered to be immediately or potentially dangerous..

None-compliance with current regulations does not automatically mean something is dangerous, it could just require improvement..

As has already been asked can you post a picture of the existing CU..

Also a copy of the observations and recommendations on the EICR, would help a lot with evaluating what your best options are?

Sylvia · Oct 17, 2024

Lexicon said:
I need another radial circuit adding to our cu board to supply a new shed / workshop. We had an an eicr done before moving into this house a year ago and the cu was deemed unsatisfactory because in does not comply with current standards, being installed in 1979. It does have rcd protection rated at 100ma.
Can a new circuit be connected under current legislation? or is a replacement CU mandatory?

No qualified electrician will do any alterations on this CU till it is deemed satisfactory .
How are you leaving in such dangerous situation?

Murdoch · Oct 17, 2024

Sylvia said:
No qualified electrician will do any alterations on this CU till it is deemed satisfactory .
How are you leaving in such dangerous situation?

Not sure I agree with this. There are situations where an old CU may be acceptable

binky · Oct 18, 2024

Sylvia said:
No qualified electrician will do any alterations on this CU till it is deemed satisfactory .
How are you leaving in such dangerous situation?

what, with so many so called electricians telling customers if the board isn't metal it's a fail...

Lexicon · Oct 20, 2024

"The electrical installation is approx 40 years old. Wiring is PVC twin and earthing installed to the regulations at the time. No 30ma RCD protection on circuits. recommend new consumer unit and earth bonding upgrade" Part 3 summary of condition of installation

binky · Oct 20, 2024

Looks like you have an old VOELD below the board, an early form of RCD that I doubt will still be working properly.

I would agree updating the board would be a good idea. You could add an RCD in a separate enclosure next to the board for the new circuit, but could really do with RCDs on all the socket circuits, and these days we RCD all circuits anyway. By the time you've done that, it's easier and neater to change the board itself. We also have no real way of testing the MCBs are still working correctly, and after 40 years, I doubt they are. So again changing the board is recommended. But if money is too tight, you can install a new circuit with an external RCD.

Earthing and bonding will almost certainly be undersized as well, again, another reason to recommend a board change and update.

Note is say recommend, it's not actually compulsory untill you install a new circuit, because anything new must comply with today's regs.

Fleeting · Oct 20, 2024

It is an earth leakage circuit breaker.

Bruspark · Oct 20, 2024

Fleeting said:
It is an earth leakage circuit breaker.

Yep - millions of those still out there. Often work but 100mA sensitivity was never enough for proper protection - Yet most houses leaked 30 or 40 mA anyway so they got by

Rated 80A so usually found on a 100A Suppliers fuse

Lexicon · Oct 22, 2024

"I would agree updating the board would be a good idea."
"Note is say recommend, it's not actually compulsory untill you install a new circuit, because anything new must comply with today's regs."
This is actually the reply to the question I was asking and nothing else - thanks binky

Adding another circuit to and old cu

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