Earth rod installation

[muh3]

Hello all,

I just had my garden room certificated by an electrician. He said the earth reading is high but it passed but he advised to install an earth rod, I did ask before the installation if an earth rod would be needed but was told the house earth is enough I should have insisted on an extra earth rod but you try and leave it to the professionals.

I believe I have a TT System, got live and neutral coming in and earth going out to an earth rod on the house.

The consumer unit is on an internal wall and running a new earth cable is somewhat not possible. However I already have a 10mm earth for water pipe bonding on an outside wall, that is connected straight to the consumer unit. So can I just run another 10mm from that pipe to an earth rod or do I have to run a new earth cable to the consumer unit.

Thank you.

 

[EFLImpudence]

He said the earth reading is high but it passed but he advised to install an earth rod,

What was the reading?
What is the house reading.

I did ask before the installation if an earth rod would be needed but was told the house earth is enough I should have insisted on an extra earth rod but you try and leave it to the professionals.

You said it 'passed'.

I believe I have a TT System, got live and neutral coming in and earth going out to an earth rod on the house.

TT is a system that uses an earth rod.

The consumer unit is on an internal wall and running a new earth cable is somewhat not possible. However I already have a 10mm earth for water pipe bonding on an outside wall, that is connected straight to the consumer unit. So can I just run another 10mm from that pipe to an earth rod or do I have to run a new earth cable to the consumer unit.

You don't need to.

IF necessary just earth the garden room with its own rod.

Is the garden room a distance from the house or just an extension?

 

[muh3]

Hi, I don't know, all he said the reading is high but it is still a pass, I guess over time that this can worsen so he suggested a earth rod for the garden room.

Sorry I was talking about the garden room regarding the internal wall. I can either run from the pipe bonding (the garden room has a bathroom) to the rod without to much trouble but if I need to run from the CU I will need to have a cable channel along the wall which I would like to avoid.

Edit: Garden room is 40m away from the house, the SWA (3 core) is 25mm and about 60m long.

 

[EFLImpudence]

Hi, I don't know, all he said the reading is high but it is still a pass, I guess over time that this can worsen so he suggested a earth rod for the garden room.

Did you not get a certificate stating such things?

 

[ericmark]

NOTE 2:* The resistance of the installation earth electrode should be as low as practicable. A value exceeding 200 ohms may not be stable. Refer to Regulation 542.2.2.

200Ω is quite high, normally more like 60Ω with a 30 mA RCD it can go to 1667Ω, but it will show on the paperwork what it is, so what does it say?

 

[Murdochcat]

So you had it certified - for what reason? And what certificate have you been given?

 

[muh3]

Hi all, the certificate will be emailed within the next 28 days. It is a new install and I assume that is the sign off to confirm with building regs.

 

[flameport]

the certificate will be emailed within the next 28 days.

Why so long?
It's a document with the circuit details and test results on it, which the person surely must already have as the work has been completed.

I assume that is the sign off to confirm with building regs.

That is an entirely different and unrelated item.

 

[Murdochcat]

Hi all, the certificate will be emailed within the next 28 days. It is a new install and I assume that is the sign off to confirm with building regs.

So assuming you are in England or Wales the spark owes you an EIC and the part P

The spark should have sent you the EIC with the invoice

 

[Taylortwocities]

the spark owes you an EIC and the part P

Eh? Part P? You must get this right.
Part P is a building regulation and this mandates electrical safety for all electrical work.
What I think you are struggling to say is that the householder should receive a Certificate of Completion. This states compliance with various parts of Building Regulations. It is usually sent from the electrician's Competence organisation (NICEIC, etc) to LABC with a copy to the client.

Things get much more difficult if the electrcican is not a member of a Competence Scheme.