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I have just had a new supply put into my 1940s semi, previously had no proper earth. Consequently nothing is bonded apart from the gas pipe,
would it be adequate to use 6mm cable to bond the sink, hot & cold pipes central heating pipes, combi boiler, Shower etc.

The house was professionally rewired 6 years ago, & they used tha gas pipe as an earth.

Cheers

JonB
 
What sort of supply do you now have? TN-S/TN-C-S or TT?

Main equipotential bonding should be at least 10mm², some DNOs ask for 16mm².

Supplementary equipotential bonding should be 4mm² (or possibly 6mm², but this is very unlikely).

There are no requirements for supplementary equipotential bonding in kitchens.

If you are going to do this work you should:

1) Get a copy of the On Site Guide, and in the meantime read these:

http://www.tlc-direct.co.uk/Book/5.4.3.htm

http://www.tlc-direct.co.uk/Book/5.1.1.htm

http://www.tlc-direct.co.uk/Book/7.2.1.htm


2) Familiarise yourself with Part P of the Building Regulations, as the supplementary equipotential bonding in the bathroom is notifiable work, and you need to make an informed decision about what you're going to do about that.
 
Thanks for the prompt reply, I am not sure what type of supply, no markings on the new bits, but I watched the guy making of the new cable, it was an aluminium centre core with multistrand earth and neutral.
 
If there were separate earth and neutral strands, then it is slpit concentric, and T-N-S (S for separated)
If there was only inner (live) and a combined Earth and Neutral armour wrap, then it is TNC (C for Combined) and earth is 'regenerated' from the neutral at the box under the company fuse. (this is also called PME , protective multipe earthing.)
In general PME requires more care with the earthing, as any supply side neutral fault can cause large earth currents to flow, and may make the metalwork inside the house live.
For PME the earthing of installations like outbuildings that may have a partly conductive floor, (perhaps damp cement, not DPC in a garage) or may involve hand held metal bodied equipment in use outside (car repairs are a classic) becomes problematic, and best practice is to have a local earth spike and RCD for them, and not to use the company earth in that case.
 
ban-all-sheds said:
2) Familiarise yourself with Part P of the Building Regulations, as the supplementary equipotential bonding in the bathroom is notifiable work, and you need to make an informed decision about what you're going to do about that.

Ban, as I understand it from the ODPM, no bonding work is notifiable, even in special locs. Furthermore, the ODPM told me that changing a CU was notifiable, regardless of where it is located. I shall check these two points this afternoon.

Just spoken to Ken Bromley at ODPM (020 7944 4400) and he informs me that bonding work in special locations IS notifiable, but outside special locations, it is not.

He also confirmed that changing a CU is notifiable regardless of location, because it is not classed as a "Minor Works".

He also told me that the LA's have the power to relax or dispense with certain requirements of Part P.

The ODPM, he goes on to say, relies on LA's and electricians to inform customers of the new regulations.

Ha,ha!!
 
securespark said:
Just spoken to Ken Bromley at ODPM (020 7944 4400) and he informs me that bonding work in special locations IS notifiable, but outside special locations, it is not.
There was no need to speak to the ODPM - If you look at what actual law says, you'll see this:
[code:1]
PART 2


NEW SCHEDULE 2B TO THE BUILDING REGULATIONS 2000




SCHEDULE 2B
Regulation 12(5)



DESCRIPTIONS OF WORK WHERE NO BUILDING NOTICE OR DEPOSIT OF FULL PLANS REQUIRED


1. Work consisting of -


(a) replacing any socket-outlet, control switch or ceiling rose;

(b) replacing a damaged cable for a single circuit only;

(c) re-fixing or replacing enclosures of existing installation components, where the circuit protective measures are unaffected;

(d) providing mechanical protection to an existing fixed installation, where the circuit protective measures and current carrying capacity of conductors are unaffected by the increased thermal insulation.



2. Work which -


(a) is not in a kitchen, or a special location,

(b) does not involve work on a special installation, and

(c) consists of -


(i) adding light fittings and switches to an existing circuit;

(ii) adding socket outlets and fused spurs to an existing ring or radial circuit; or

(iii) installing or upgrading main or supplementary equipotential bonding.



3. Work on -


(a) telephone wiring or extra-low voltage wiring for the purposes of communications, information technology, signalling, control and similar purposes, where the wiring is not in a special location;

(b) equipment associated with the wiring referred to in sub-paragraph (a).[/code:1]

So installing or upgrading bonding is non-notifiable only if it's not in a kitchen or a special location.

He also confirmed that changing a CU is notifiable regardless of location, because it is not classed as a "Minor Works".
Interesting that he feels that he can make arbitrary decisions about what is or is not notifiable. There is no mention of the term "Minor Works" in the law. Ken Bromley can say what he like, but he might as well say that work only becomes notifiable if done by a red-haired electrician for all the legal status his sayings have.

That said, in a brazen display of hypocritical inconsistency, if I wanted to replace my CU, I would use the advice from the ODPM.

Here http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/page/odpm_breg_033480.hcsp

and here: http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/page/odpm_breg_033485.pdf

it says:

You do not need to tell your local authority’s Building Control Department about:

  • repairs, replacements and maintenance work; or
  • extra power points or lighting points or other alterations to existing circuits (except in a kitchen or bathroom, or outdoors).
I would say that it's perfectly reasonable to class a new CU as "repairs, replacements and maintenance work"....

He also told me that the LA's have the power to relax or dispense with certain requirements of Part P.
I think that LABCs have the power to relax or dispense with the entire Building Regs if they want...

The ODPM, he goes on to say, relies on LA's and electricians to inform customers of the new regulations.
Like any electrician registered with the COR scheme is going to do that...
 
Thanks for the input,
But are we saying that I can`t put a bonding cable between my sink and gas pipe without asking permission.
JonB
 
JonB said:
Thanks for the input,
But are we saying that I can`t put a bonding cable between my sink and gas pipe without asking permission.
JonB

you either: do the bonding work and pay to have it inspected

or dont do the work and dont pay.

or do the work, and **** LABC. your making the earthing system safer.

id go with #3
 
JonB said:
But are we saying that I can`t put a bonding cable between my sink and gas pipe without asking permission.
You don't need to put a bonding cable between your sink and your gas pipe.

Andrew missed out #4: Get an electrician in.

But personally I'd go with #3 as well.
 
I went to an interesting mini seminar on Part P given by an Ealing Building control Team Leader last Tuesday.

He agreed that bonding a kitchen sink was not required under the regulations due to a loophole but said that anyone who did not do so could be seriously liable in case of any accident and so would be a fool if they did not.

He also said they interpreted the "kitchen" RCD to be required in the WHOLE room space where the kitchen was INCLUDING the front room if there was through lounge!

He did agree that although against the regulations having the freezer on a non RCD circuit was acceptable to them!

He also said that they were inspecting ALL Part P installations ( unless Certified ) because of the safety implications whereas they might not bother with footings etc. if they were busy.

He was also adament that CU work was always notifyable!!

He also said they strongly recommended whole house on RCDs ( including burgular/fire alarms! On a separate RCD though! )

Tony Glazier
 
That Ealing team leader is a bit OTM.

Even the IEE say it is no longer necessary to bond in kitchens. They even said it can make it more dangerous than before it was bonded....
 

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