Bonding Gas Supply in an Outbuilding

[Piratepete]

Hi Guys
Doing an EICR of a property.
The client has an outbuilding with gas and water supplies. It has it's own CU fed from the main CU in the house.
The water is bonded but the gas is not.
The water supply is underground from the house in plastic and then changes to copper which is bonded.

The gas supply comes from the house in an underground copper pipe linked to the gas pipes in the house. So, electrically, it would be subject to the bonding in the house.
But does this negate the need to bond it in the outbuilding?

Looking forward to wise words!

Cheers
Pete

 

[Engineer54]

NO, it doesn't negate main bonding to the outbuildings CU (EMT) especially if the supply is PME, in which case the sub-main earth should be a minimum of 10mm....

 

[TJ Anderson]

NO, it doesn't negate main bonding to the outbuildings CU (EMT) especially if the supply is PME, in which case the sub-main earth should be a minimum of 10mm....

I read it that he is saying the gas is bonded in the house and is in copper pipe to outbuilding so is bonded already. The Water they have bonded in outbuilding because it has plastic pipework across to it.

 

[Engineer54]

I read it that he is saying the gas is bonded in the house and is in copper pipe to outbuilding so is bonded already. The Water they have bonded in outbuilding because it has plastic pipework across to it.

It doesn't matter a jot whether the gas pipe is bonded at the main house or not, it still needs bonding at the outbuilding....

 

[davesparks]

There are some very clear pictures in guidance note 8 which make the situation crystal clear.

 

[Piratepete]

I read it that he is saying the gas is bonded in the house and is in copper pipe to outbuilding so is bonded already. The Water they have bonded in outbuilding because it has plastic pipework across to it.

Yes. your interpretation is correct.
My immediate thought was that it should be bonded, but I couldn't understand why it hadn't been done as the gas supply is an easy connection within 2 metres of the CU and all services were put in at the same time, 10 years ago. The water stopcock and bonding point are miles away.
Pete

 

[Engineer54]

There are some very clear pictures in guidance note 8 which make the situation crystal clear.

Never found the need to use that particular picture book Dave... lol!!

 

[davesparks]

Never found the need to use that particular picture book Dave... lol!!

I'm sure you haven't, but for anyone learning about this it makes it all very clear, which is admittedly very rare for the IET.

 

[Deleted member 26818]

Disconnect the bond to the water, and use it for the gas.

 

[Deleted member 26818]

I'm sure you haven't, but for anyone learning about this it makes it all very clear, which is admittedly very rare for the IET.

Remember the GNs are not written by the IET, only printed by them.

 

[Piratepete]

There are some very clear pictures in guidance note 8 which make the situation crystal clear.

That's £29! Anyway I need the answer for tomorrow when I present my list of remediakls to the client!

 

[TJ Anderson]

Disconnect the bond to the water, and use it for the gas.

Surely he should prove it is not extraneous first?

 

[davesparks]

That's £29! Anyway I need the answer for tomorrow when I present my list of remediakls to the client!

So you're carrying out EICRs without adequate knowledge of the basics of bonding or a full set of reference books to help you?

 

[Deleted member 26818]

He can prove it if he wants to.

 

[TJ Anderson]

He can prove it if he wants to.

Would you not then?

 

[Deleted member 26818]

No.....

 

[TJ Anderson]

It may require it.

 

[davesparks]

No.....

So with no more information than a blue plastic pipe entering a building and then converting to copper you have decided it does not need bonding? Without any information as to where that copper goes or how it is installed which could make it extraneous?

 

[Simlec]

It may require it.

Its plastic lol

 

[TJ Anderson]

Its plastic lol

No. The installation in outbuilding is copper. Read the post properly.

 

[Deleted member 26818]

So with no more information than a blue plastic pipe entering a building and then converting to copper you have decided it does not need bonding? Without any information as to where that copper goes or how it is installed which could make it extraneous?

You need to google the definition of extraneous.

 

[Simlec]

No. The installation in outbuilding is copper. Read the post properly.

NO the incoming pipe is plastic.

 

[TJ Anderson]

NO the incoming pipe is plastic.

So what?

 

[Deleted member 26818]

So what?

Being plastic, it is not an extraneous-conductive part, and does not require bonding.

 

[Simlec]

TJ back to school !

 

[TJ Anderson]

Im not talking about the plastic pipe. I am talking about the copper installation in the outbuilding. You do not know that it is not extraneous without testing it first.

 

[TJ Anderson]

TJ back to school !

Think again. It is you that does not understand. I am saying the only way you can prove that copper pipework is not extraneous is by testing. You are making assumptions.

 

[HandySparks]

Im not talking about the plastic pipe. I am talking about the copper installation in the outbuilding. You do not know that it is not extraneous without testing it first.

Indeed. But if testing shows it to be extraneous, the problem may be working out WHY it's extraneous and therefore WHERE it should be bonded.

 

[TJ Anderson]

Indeed. But if testing shows it to be extraneous, the problem may be working out WHY it's extraneous and therefore WHERE it should be bonded.

That is my point. But to get to that stage, you would have to test it first, prove if it is extraneous or not and then go from there.

 

[Simlec]

Well when I went to school plastic did not make a good material for conducting electricity.

 

[Deleted member 26818]

Im not talking about the plastic pipe. I am talking about the copper installation in the outbuilding. You do not know that it is not extraneous without testing it first.

Again, the definition of extraneous needs to be googled.

 

[TJ Anderson]

Well when I went to school plastic did not make a good material for conducting electricity.

Read post #26!! I know the plastic pipe is not conductive ffs. I am talking with regard to the copper installation in the outbuilding. We know nothing about it from the OP's opening post so you cannot possibly know if it is extraneous or not as you don't have enough information to make that judgement.

 

[davesparks]

You need to google the definition of extraneous.

No I don't, the definition of the word extraneous won't help at all.

Bs7671 defines the term 'extraneous conductive part' in the context of electrical installations.

 

[TJ Anderson]

Again, the definition of extraneous needs to be googled.

I know what an extraneous conductive part is and what defines it (Extraneous-conductive-part: A conductive part liable to introduce a potential, generally earth potential, and not forming part of the electrical installation). How do you know it is not from the limited information the OP has provided regarding the copper installation pipework?

 

[davesparks]

NO the incoming pipe is plastic.

Yes the incoming pipe is plastic, but the installation it feeds is copper. There is no information as to how extensive the copper installation is or whether it is all surface pipework on plastic clips or mostly buried in the concrete floor structure or it could even go back underground as copper to feed another building.

Without further information there is no way to know whether or not the installation pipework will be an extraneous conductive part.

 

[HandySparks]

Yes the incoming pipe is plastic, but the installation it feeds is copper. There is no information as to how extensive the copper installation is or whether it is all surface pipework on plastic clips or mostly buried in the concrete floor structure or it could even go back underground as copper to feed another building.

Without further information there is no way to know whether or not the installation pipework will be an extraneous conductive part.

544.1.2 says "The main protective bonding connection to any gas, water or other service shall be made as near as practicable to the point of entry of that service into the premises."

Since it refers to the point of entry of the service, rather than the point of entry of the pipework, it appears to be saying that, even if the reason that the copper pipework is extraneous is that it feeds out underground in copper, the main bond should still be made at the incoming point.

 

[Simlec]

Yes the incoming pipe is plastic, but the installation it feeds is copper. There is no information as to how extensive the copper installation is or whether it is all surface pipework on plastic clips or mostly buried in the concrete floor structure or it could even go back underground as copper to feed another building.

Without further information there is no way to know whether or not the installation pipework will be an extraneous conductive part.

So the incoming pipe is plastic with a bond on it that's not needed. Ok we got there.
Yes it could go underground again (like the gas has and we said move the bond over to that pipe), and if it was copper then it would be bonded at that point would it not.
Am I right in thinking if a house had plastic gas & water incoming pipes and copper installation pipes that did not go underground again, you would bond the pipe work?
TJ, I think your comment of the word "Stupid" over steps the mark!!

 

[davesparks]

544.1.2 says "The main protective bonding connection to any gas, water or other service shall be made as near as practicable to the point of entry of that service into the premises."

Since it refers to the point of entry of the service, rather than the point of entry of the pipework, it appears to be saying that, even if the reason that the copper pipework is extraneous is that it feeds out underground in copper, the main bond should still be made at the incoming point.

Which supports my point exactly.

Although you would have to check exactly what they mean when they say 'service' and how you apply it. I would say in the situation that it is not the incoming service which is being bonded but the installation pipework and as such would be best to be bonded at the point that the extraneous part enters the installation.

 

[Knobhead]

?

Yes. your interpretation is correct.
My immediate thought was that it should be bonded, but I couldn't understand why it hadn't been done as the gas supply is an easy connection within 2 metres of the CU and all services were put in at the same time, 10 years ago. The water stopcock and bonding point are miles away.
Pete

Did it comply then?

 

[HandySparks]

Which supports my point exactly.

Although you would have to check exactly what they mean when they say 'service' and how you apply it. I would say in the situation that it is not the incoming service which is being bonded but the installation pipework and as such would be best to be bonded at the point that the extraneous part enters the installation.

I agree. It would be better to bond at the point where the metallic pipework enters the building, which isn't what the regs appear to be saying.