Do I need to bond my cold water main?

mogget

mogget

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I currently have a bond to the MET on my gas pipe, as per gas regs. There is no bonding on the rising main, which comes in in MDPE before switching to copper at the stop valve. The pipes at the boiler are cross-bonded. I have a TT installation with an earth rod, a Wylex NS consumer unit, and a 30mA RCD protecting the whole house. I get the occasional nuisance trip a couple of times per year. The electrical installation is circa 1987 I think.

Do I need to bond the water pipe to the MET?

It's on the other side of the house so don't want to bond it if I don't need to. I don't fully understand bonding, why it's done and the regs surrounding it.

Thanks Folks.
 
mogget said:
I currently have a bond to the MET on my gas pipe, as per gas regs. There is no bonding on the rising main, which comes in in MDPE before switching to copper at the stop valve. ... Do I need to bond the water pipe to the MET?
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No. The only things that need main bonding are conductive (i.e. metal) pipes etc. which enter your house from outside. If, as you appear to be saying, your water supply enters the house in MDPE, then there is nothing which you need to (or could!) bond.

Kind Regards, John
 
JohnW2 said:
No. The only things that need main bonding are conductive (i.e. metal) pipes etc. which enter your house from outside. If, as you appear to be saying, your water supply enters the house in MDPE, then there is nothing which you need to (or could!) bond.

Kind Regards, John
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Interestingly though some DNOs will require it. For example, NIE will insist on the inside copper pipework being bonded (unless this has recently changed with them).

I know that the NICEIC have tried to get them to shift from this position but to no avail.
 
That's interesting. I don't know who my DNO is but I'm in the old Southern Electric area.

Is the cross-bonding at the boiler still mandated by the current electrical regulations?
 
Risteard said:
Interestingly though some DNOs will require it. For example, NIE will insist on the inside copper pipework being bonded (unless this has recently changed with them).
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Well, whatever their reasoning, and whatever their perceived purpose, whatever it is that they are requiring is NOT 'main bonding' ('PEB' or whatever) - since that only applies to extraneous-conductive-parts, so if the water enters the property in a non-conductor (plastic pipe), there is no extraneous-c-p to main bond. They are therefoore taling about some sort of 'supplementary bonding' - but not really of a type which is recognised by current (UK) regulations.

As often discussed here, to unnecessarily connect internal metal pipework to earth can actually increase the risk of electric shocks - although, in practice (unless there are bits of plastic plumbing involved), such pipework is usually unavoidably connected to earth 'incidentally', by virtue of its connection to boilers, electrical CH components, immersions etc.

However, that is not inevitably the case (since some properties do have bits of plastic plumbing), so it is very odd ('irresponsible'?) that any DNO should 'insist' on something 'unnecessary' which, under certain circumstances, would increase the risk of electric shocks!

Kind Regards, John
 
mogget said:
That's interesting. I don't know who my DNO is but I'm in the old Southern Electric area.
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I don't think you'll find any DNO in 'mainland UK' taking the view that Risteard reported.
mogget said:
Is the cross-bonding at the boiler still mandated by the current electrical regulations?
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Definitely not. The only sort of 'cross bonding' (supplementary bonding) which may sometimes be required by current regs (and even this, only rarely required) is in bathrooms (and saunas, swimming pools etc.!).

Kind Regards, John
 
Risteard said:
Interestingly though some DNOs will require it. For example, NIE will insist on the inside copper pipework being bonded (unless this has recently changed with them).
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I am not as diplomatic as John - they are wrong and obviously do not know what they are talking about.

What are your thoughts on, presumably, having to do what is wrong (and possibly hazardous) to satisfy numpties?



Never assume those in charge know what they are doing.
 
EFLImpudence said:
I am not as diplomatic as John - they are wrong and obviously do not know what they are talking about. What are your thoughts on, presumably, having to do what is wrong (and possibly hazardous) to satisfy numpties?
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I suppose that, were I in a region such as Risteard described, I might have to reluctantly moderate my 'thoughts' if the situation were such that if I didn't satisfy the numpties, I would be denied an electricity supply!

One obviously could try 'fighting' but, quite apart from the considerable (and undoubtedly protracted, whilst one had no electricity!) hassle which would be involved, I'm not sure whom one could 'appeal to' in relation to 'established practice' of a DNO (if that's what it is)!

Kind Regards, John
 
I suppose one could/would connect a bond to get one's electricity and then disconnect it as soon as they had left.

One could then correspond with the DNO and attempt to enlighten them - or do you think blindly following their instructions 'for ever' is a satisfactory state of affairs?



What about suggesting connecting an earth rod to the pipe so that it does need bonding?
 
EFLImpudence said:
I suppose one could/would connect a bond to get one's electricity and then disconnect it as soon as they had left.
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One could - but, as you go on to imply, that would constitute 'giving in' in relation to the 'mattrer of principle'!
EFLImpudence said:
One could then correspond with the DNO and attempt to enlighten them....
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Indeed, but depending on how silly they are, they might come and disconnect the supply if you told them that the 'required' bonding was no longer present!
EFLImpudence said:
... - or do you think blindly following their instructions 'for ever' is a satisfactory state of affairs?
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A totally unsatisfactory state of affairs. However, some might decide that 'life is too short' to get involved in the undoubted hassle of trying to deal with this as a 'matter of principle'. I could equally try to fight (as 'a matter of principle') countless other things (like being 'required' to drive at 20 mph past the local school gate at 3am during the school summer holiday!) - but my 'life priorities' mean that that doesn't happen.
EFLImpudence said:
What about suggesting connecting an earth rod to the pipe so that it does need bonding?
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In the OP's case, he almost certainly does essentially already have that situation, since his internal pipework will almost certainly be in continuity with his TT electrode - but his incoming earthing conductor will already, necessarily, be connected ('bonded', if you wish!) to his MET!

Kind Regards, John
 
I didn't say I would tell them I had disconnected the bond whilst corresponding.

How does incompetence get addressed in your world?
 
EFLImpudence said:
I didn't say I would tell them I had disconnected the bond whilst corresponding.
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Oh, fair enough.
EFLImpudence said:
How does incompetence get addressed in your world?
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Well, when it's 'institutional incompetence' usually by "investigations/enquiries" and legal processes which can go on for years, sometimes decades, and which often involve tens of thousands of man-hours of effort (and goodness knows how much money!).

Kind Regards, John
 
EFLImpudence said:
What are your thoughts on, presumably, having to do what is wrong (and possibly hazardous) to satisfy numpties?
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Essentially I have no choice.

My NICEIC Area Engineer told me that obviously the NIC will not record it as a non-conformance, but the reality is that the NIE will not connect.

A lot of NIE workers also used to insist on the MET being external from the DB (i.e. an ISCO used for it). I doubt this requirement has changed either.
 
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