Earth bonding to gas and water

28 Feb 2008
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United Kingdom
Other threads I found on this were over a year old, so I'm starting a new thread on this incase details were out of date.

We're in the process of renovating a property, and as part of the re-wiring our electrician ran an unbroken earthing cable to the gas and water pipes (doesn't look 10mm to me - but could well be). However, we need to get a new gas pipe for a new boiler, and it will be entering the property at the other end of the building.

So, should I run a new continuous loop to the water pipe and then the gas pipe, or can I just run a new cable from the water pipe clamp to the gas pipe (or from the main earthing point to the gas pipe)?

Also, I *think* the current earth cable runs to the CU; however, there is also a meter cupboard for the flat on the landing outside which seems to have several earth cables connected to a terminal in it, can I run the cable from there (which would be easier), or must it be from the CU?

Finally, he didn't mention, or install, any bonding for anything else in the bathroom. All pipes other than the gas and electric are plastic, but would metal taps, radiators, etc need earthing?

Oh, and a bit of the old gas pipe will still be present under the floorboards (the pipe then runs through the property below and the end of the hallway below that) does this still need bonding? Also, there is a gas pipe running up to the flat above. It's only visible under the floorboards, and won't be accessible once the bath is in. Will this also need bonding? (I guess it should be bonded at the flat above, as it is there gas supply, but I suspect it isn't, as ours previously wasn't).
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Are you saying the old gas incomer[which is already bonded] is being removed/replaced or that new copper pipe work is being fitted to the one thats there and new pipiework is being taken around the building then back in to your boiler?
The old gas incomer is being replaced by entirely new copper pipe work from the external meter into the flat. The new pipe work will be at the other end of the building (for various long and complex reasons).
Gas regs state meter/pipework should be earthed within 600mm of the meter and before the first T in the pipe work.

There is always a difference of opinion between gas engineers and sparks!
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Other posts I've seen on the forum suggest it can be 600mm from the point the service enters the property if the meter is external. Earthing 600mm from the metre isn't very easy, as the meter is 3 floors down in a store room under the pavement in front of the building.

Also, my question was whether it was OK for a separate earth cable to be run to the gas than the water, or if they should be on one continuous cable; and if it was OK to connect to the earthing terminal next to the electricity meter, rather than to the CU (the current cable goes to the CU, but it would be a pain to run a new cable to it now that the plastering is done.

Oh, and also what are the regs regarding earthing radiators and towel rails in a bathroom? (they are connected using plastic pipes).
the earth connection can be at the first accessible point after entry to the building, so with external meter with gas pipe under screwed/glued chipboard flooring the first "accessible" point can often be where the pipe rises through the floor to the appliance, 8-10m from external wall, electricians always prefer to bond inside the property as the connection is less likely to be subjected to corrosion etc, the main issue is whether the pipe is bonded and any subsequent test (ZE, I THINK) has a positive test result, the dimension of 600mm from the meter to the bond is to tie in with the pipework installation BS which states the first 600mm f pipe after the meter must be rigid, so asking for the bond to be within this will mean it always complies because if the pipe is changed to semi rigid etc the gas engineer must leave the first 600mm as rigid.
and is it fine to run the earth from the earth terminal in the meter cupboard, rather than from the CU?

I want to get this sorted, so that I can get on with getting the floor fixed back down properly.
As far as I know it is.

If your gas meter is so far away from the first point of entry, is it because you are in a flat or apartment?

If so earth the gas next to the ECV that should be present at the first point of entry of the gas pipe into your property.
If so earth the gas next to the ECV that should be present at the first point of entry of the gas pipe into your property.
Hmm, we're heading squarely into gas territory here, rather than electrics (so maybe a mod could move this), but when they install the new pipe, where exactly is the ECV going to need to go? Will it have to go right where the pipe enters the property, or does it just have to be before the first appliance and/or junction in the pipe?

I'm assuming that it can't be below the floorboards, as I'm assuming the regs (and common sense) state something like "must be accessible without the use of tools".

The pipe will be entering the property in the 3rd bedroom*, which would not be an ideal location for the ECV. The pipe will then run below the flooring to the kitchen, where the boiler will be located. There is also a tee in the pipe in the kitchen where a feed goes off to two gas fire places.

The ideal location for the ECV would be in the cupboard in the kitchen next to the boiler - will this be compliant though?

I'm sure the installer will take me through what is allowed, but I may as well be prepared for the worst.

* (this is the only place it can enter, as it is a listed building, and it took some persuasion to get the council to agree to running the pipe anywhere on the exterior of the building - in the end they agreed that it could be run between the soil pipe and drain pipe on the end wall, and the freeholder was not happy with the idea of it being run internally)
If the bond is made at a point further than 600mm from the stop cock (perhaps for the reasons above) then I always attach a durable notice at the gas meter and at the consumer unit indicating where the bond is made.

That way any future gas folk or sparkies on site know that the gas service is bonded and where the bond is located.
The PEB for gas & water can be run in one cable as long as it is continuous, ie unbroken at the clamps.
The ECV must be at the first point of entry that the gas pipe becomes visible in the flat. Ideally this will be as close as possible to where the gas pipe acually enters the property (albeit under floorboards etc) with the gas pipe surfacing just for the ECV to be fitted then disappearing back under the boards.

This will enable as little gas pipe work to be 'uncontrolled' as possible in case you ever smelt gas.

As you say though your RGI should explain all this to you.

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