New kitchen earthing

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Hi, i have just built an extension to my utility room and made it into a large kitchen, to do this i have used the existing consumer unit to supply a new ring main and lighting circuits. I have fitted a new cooker with gas supply a new sink and two radiators fed from an existing com-bi gas boiler in the corner of what was the old utility room.
What i need to know is what sort of earthing or earth bond and size of cable is required apart from the earth which is in the 2.5mm twin & earth ring main cable fed from the consumer unit.
 
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Do the water and gas supplies have a main bond where they enter the building, preferably within 60cm and before any tees?
 
No the house was built about 40 years ago and an annex added 20 years ago but the only bond is below the consumer unit, which is to the gas pipe and the hot and cold water supply to the old kitchen.
If it helps to know that the mains water valve and the gas supply to the house are below the com-bi boiler which in turn then supplies the central heating system, all hot and cold water to the house, and a tee to the gas cooker.
Although the boiler is about eight meters from the outside gas meter I could take a wire from it to the consumer unit?
 
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You can use one main protective bonding cable to link the water and gas together where they enter the premises and then continue onto the Main Earthing Terminal which is either the earth bar in your Consumer Unit or a block adjacent to it.
This cable needs to remain uncut throughout it's length.
What is your supply type, TN-S, TN-CS, TT?
 
You can use one main protective bonding cable to link the water and gas together where they enter the premises and then continue onto the Main Earthing Terminal which is either the earth bar in your Consumer Unit or a block adjacent to it.
This cable needs to remain uncut throughout it's length.
What is your supply type, TN-S, TN-CS, TT?

TT being where the earth is from a rod inserted into the ground.
TN-S is when the earth is fed seperatly or taken from the sheathing of the incoming cable
TNC-S is when the earth comes from the incoming neutral on the cutout
 
TN-S by the looks of things, I have just looked at the supply from the electricity boards meter and there is a 10mm single earth from their meter to my consumer unit, does this mean I now need another 10mm from my consumer unit to the boiler (15mtrs of cable) or is the fact that there is already a bond to the gas and water pipes below the consumer unit enough?
Someone mentioned that I may need to bond each radiator the sink etc directly back to the consumer unit or is this an exaggeration?
 
I should have mentioned that my reasons for making sure I get it right is because I need building regs to sign off the work done to the kitchen which needed planning permission to start.
 
TN-S by the looks of things, I have just looked at the supply from the electricity boards meter and there is a 10mm single earth from their meter to my consumer unit, does this mean I now need another 10mm from my consumer unit to the boiler (15mtrs of cable) or is the fact that there is already a bond to the gas and water pipes below the consumer unit enough?

You will likely have an earth from the incoming cable sheath to an earth block, provided by the supplier. To conform to current regs you need 16mm earth cable from supplier's earth to your CU via the earth block. Then 10mm earth from either your earth block or CU to your service pipes' entry point to the building (close as possible) as Sparklms and spark123 have already said.

Someone mentioned that I may need to bond each radiator the sink etc directly back to the consumer unit or is this an exaggeration?

If you have an RCD for the kitchen circuits, and you most likely should have one or have fitted one, then equipotential bonding is not needed.

If you have managed to satisfy all the requirements for NOT having an RCD (and there are many) then you need equipotential bonding,
but not quite in the manner you described...
 
:rolleyes:
I think we mean 'supplementary' bonding in the last part of the above post ? ;)
Ed
 
There isn't a requirement for "supplementary equipotential bonding" in a kitchen regardless of the requirements for RCD protection.
There is a requirement to provide "Main protective equipotential bonding" of extraneous conductive parts such as the water supply and gas supply regardless of where they enter the premesis which is what we were talking about above above.
I think the requirement for supplementary equipotential bonding in kitchens was binned back in the 15th edition??
 
FFS...

The only bonding you need is that the incoming gas and water mains are bonded with 10mm as they enter the premises. There is no need to "earth" the sink or "bond" the boiler.

Have you been reading Davey Knobfire's book? :LOL:
 
I stand gratefully corrected about the supplementary bonding in the kitchen! Think I was confusing kitchen with bathroom (something I've done before, but nothing to do with electrics... ;))
 
Cheers Echoes.
Everyone slips up from time to time as we know. ;)
Regards
Ed
 
Have you been reading Davey Knobfire's book?

Certainly not, but I have been following the saga on here. Looks like some of it has still rubbed off though. :oops:
 

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