Where to bond?

[chops]

Been to domestic installation and found that the water and gas are not bonded. The water appears straightforward, however the gas is not so.

The gas service currently enters the house under the floor. A heating engineer has previously teed off here and taken a supply back outside the house and up into the loft to a new boiler installation.

Where would you guys bond to? I'm not going to bond under the floor - access issues for inspection etc, although this means that I'm bonding after branched pipework. I could bond outside, near the ground, and run the bonding up the outside wall and across the loft towards the MET on the other side of the house. This may lead to mechanical damage or corrosion issues. Or I could simply bond in the loft where the gas pipe enters.

Any thoughts?

 

[The Godfather]

Any thoughts?

As close as possible, without causing unreasonable damage to the property.

In this instance I would ensure there is information readily available regarding the Gas bonding (position).

Regulations do allow for this.

Don

 

[Andy™]

maybe sweat the earth to the pipe under the floor, and leave a note at the CU with details of its location?

or maybe put the clamp outside? (assuming its an outdoor meter?)

 

[Mark2spark]

I thought the reg for gas was to bond within 600mm of the meter?

Or I could simply bond in the loft where the gas pipe enters.

That would be the more obvious option.

Where's the meter?

 

[Andy™]

I thought the reg for gas was to bond within 600mm of the meter?

or point of entry.

 

[chops]

Thanks for the replys guys.

Meter is at the front of the property about 50 metres away! (an old farm). Supply runs underground and then pops up at an outside wall before disappearing into the property under the floor.

The regs state within 600mm where practical.

So the choice is either under the floor - problems with inspections, outside - possible problems with mechanical damage and corrosion, and its after a branch. Or in the loft - over 5 metres away from where the supply originally enters the house, and again after branched pipework.

At least this sort of stuff keeps me off the streets!

 

[binky]

Go for loft - 600mm is a recommendation not a tablet in stone, and copper pipe is a damn good conductor.

 

[M107]

I'd go for on the riser outside & user an EC15 myself & make a note on the cert of where the bond is.

 

[batty]

I'd go for on the riser outside & user an EC15 myself & make a note on the cert of where the bond is.

M just pointing out thats a blue not red earth clamp as used by others as you know. Outside is ok as long its a suitable clamp ie suitable for damp conditions.

Batty

 

[green-hornet]

All bonding has to be accessable, M107 has the best answer here because of the nature of access and verification.

All deviations from the regs can be noted on the certificate, a deviation does not imply it is outside the regulations, simply that under the circumstances it has not been possible to comply fully with the "guidlines".

Take for example emergency lighting, they have to be fixed at least 2 m from the floor, but if the ceiling height is 1.75m this would be noted on the certificate as a non compliance but that does not mean it is outside the regulations.

 

[a1]

Within 600mm or where reasonably practicable.

 

[springcrocus]

The regs state within 600mm where practical.

I'm playing "Devils advocate" here.

Why is the first 600mm of pipework any better that the next 5 metres or so? The amount of copper in the cross-section of a 15mm or 22mm copper pipe (ignoring the fact it's a pipe) is still greater than the amount of copper in a 10mm bonding conductor, so why not bond somewhere near to the CU?

If you decided to bond the gas pipe to the MET using 15mm copper pipe instead of 10mm copper wire, I bet you would find that the resistance of this "conductor" is actually less (even if it's impracticable). Anybody want to test this by measuring the resistance of 25 metres of 15mm copper pipe and 25 metres of 10mm copper wire?

This regulation, albeit advisory, sounds like somebody picked a number out of a hat because somebody else said, "Well, we need to provide a guideline".

Although I try to follow the guidline, I think it's ballcocks. ]

 

[a1]

The regs state within 600mm where practical.

Within 600mm or where reasonably practicable.

Pays to read thoroughly, what peple have typed out. :_|

PS, Welcome to the forum Chops.

 

[springcrocus]

But lots of people seem to think that 600mm is some sort of magic number. My argument is that it matters not one whit where you bond to the pipework, as long as you can get to the connection for maintainence purposes.

If this happens to be 25 yards away from the point of entry to the building, so be it.

To my mind, an example of a regulation for the sake of a regulation.

 

[green-hornet]

The only "logical" explanation would be "to conform", that is within 600mm is a figure that would allow future electricians to a, find the bonding and b, verify the bonding.

You do NOT need to bond within 600mm if it is impracticable or for testing and verification purposes is not accessable.

Within 600mm is also a figure that would normally imply that no branches have been taken from the supply as yet.

Originally Posted by Admin

Within 600mm or where reasonably practicable.

Best answer and should be noted on your certificate as to the position of gas bonding.

 

[Theorysparky]

The only "logical" explanation would be "to conform", that is within 600mm is a figure that would allow future electricians to a, find the bonding and b, verify the bonding.You do NOT need to bond within 600mm if it is impracticable or for testing and verification purposes is not accessable.

Within 600mm is also a figure that would normally imply that no branches have been taken from the supply as yet.

Originally Posted by Admin

Within 600mm or where reasonably practicable.

Best answer and should be noted on your certificate as to the position of gas bonding.

And that is that Guiness Drink

 

[Gforce]

According to my niceic installation handbook 17th edition it is fine to terminate outside in a gas box if the pipe entering the property is inaccessable

 

[chops]

Thanks for everones input. I'll forget about under the floor. I will bond where the pipework re-emerges outside the property and then loop into another bond clamp in the loft for belt and braces in case of mechanical damage issues to the outside clamp in the future.

Chops

 

[daryl631]

Have done one of these meter outside pipe ran up wall into loft space so i bonded in the loft space just after entry like the guide says 600mm of entry

 

[steptoe]

sorry guys, but where oh where does it say you CAN bond outside?

if you want to follow the big red comic then do so, and bond where it enters the property, dont worry about the 600mm, just accessible.

if you bond outside the property then you are by default extending the equipotential zone to outside!!!!!! impossible to encase your zone, IMHO, or do you draw a loop around the garden fence??????