ELECTRICIANS HELP? earth bonding in bathrooms?

Question

i am connecting all the metal work in my bathroom with bonding clips and 6mm cable.can i put the bonding clips under the floor boards just before the pipes begin to rise? (the pipes are going to be sprayed so becoming a feature in the bathroom, i would prefer not having the bonding clips on view) do i connect the earth to the consumer unit. i used to be a electrician a long time ago not really shaw on the current regs cheers

Answer 1

As long as the pipes are cross bonded (all pipes hot and cold and metal bath and radiator pipes are connected via 6mm earth cable) is fine, no need to take it back to the consumer unit.
But you should have the cross-bonding visible, so it can been seen. But i understand the rules are changing (April 2008), not sure what the new rules will be yet.
If, for instance, a person comes into contact with a conductive part that is at a potential difference to earthed metalwork and
that metalwork; then a very serious shock can result. In order to eliminate this possibility, all electrical earths of circuits supplying equipment in the bathroom and all extraneous conductive parts are bonded together. In this way, even if a potential does develop, such as during an earth fault on one of the electrical circuits, all the conductive parts that someone could touch will be at substantially the same voltage. No dangerous shock current can then flow.
(plumber, not a electrician)
I understand this is not covered in part p so you can do your own cross bonding connection.
hope this helps.

Answer 2

The earth bonding wiring for gas and water pipes is hardly ever trunked or laid in conduit so what he did wasn't unusual. However he should have left it tidy. You could try calling him back to attend to the cosmetic issues but he'll probably ask why you didn't mention it at the time. There is no safety issue regarding the location of the bond to the water pipe. The copper pipe itself is a very good conductor so as long as the copper pipe run isn't broken by plastic fittings the earthing will be very good. In fact, the most probable cause of the water pipe becoming Live would be a fault in the boiler - so an earth connection by there is better than further away at the stop cok. (Why doesn't the Yahoo's American editor recognise that c-o-c-k is a legitimate English word?).

Answer 3

All earth clamps with screw connections must be accessable for inspection but you can solder the wires onto the pipes under the floor boards, DONT take a cable back to the consumer unit this could introduce a potential if a fault occured elsewhere in the system. Do connect the bonding to the earth of all the electrical circuits witin the bathroom thereby creating a "Faraday Cage" which will not allow any potential difference between all earthed metal in the bathroom. Next year the regulations change in respect of earth bonding witin bathrooms but at present do as above.

Answer 4

If you bond where you don't have to (where for example the metalwork was isolated from earth then you create a shock risk, not reduce one...

If all your pipework is copper, then with a minimum of 2.5mm (NICEIC say 4mm, but that's their rules).
Connect hot pipe to cold pipe to the cpc (earth wire) of each circuit in the bathroom. You DO NOT run it directly back to the main board.

So if you had a heater towel rail, and lights, and electric shower there would be a bond between the cpc of them all at the bathroom, which continues on to the piepwork

Answer 5

It hasnt changed that much!

-You need to run a 10mm from the consumer unit to the main incoming water supply and clamp it to your side of the stop c0ck.
-You need a 10mm cross bond across the Hot and cold pipes under the sink, shower/bath
-and a 4mm linking the lighting, radiator, cross bond, and any other incoming circuit into that bathroom

Yes you can put them under the floorboards (due to the fact that they are accessible because floorboards can be lifted!!!)but your gonna have a problem with the radiator clamp (If you have a radiator that is) because that needs to be attached to the radiator really

Answer 6

A cold water pipe bond is required by the N.E.C. code. to prevent electrical shocking by grounding ALL metal pipes to the main electrical system. A #8 awg. copper wire can be connected at an assessible point on the cold water side of a water heater or outside water spigot or at the cold water entrance pipe. It does not need to be bonded at each water outlet.

Answer 7

The regs require a 4mm bond from a local source ie earth on a light fitting or socket in a close room-as well as the cross bonding.

Answer 8

Yes you can wire as you suggest under floor boards, inc' back to main consumer unit! 16th edition regs.
Just a little tip here you can buy buy a very good little book Collins DIY guide wiring &lighting, save trying to plough through the 16th edition. The book is about £5.
The bit I am not sure about is this new law ref what bits of wiring you are allowed to do and what you are not allowed to do. This bit could affect your insurance?

Answer 9

SHAW?
How can you train to be a qualified electrician and not be able to spell 'sure'. What is it with the spelling on this site?

Answer 10

YOU CAN PUT THEM UNDER THE PIPES AND YOU MUST CONNECT THE EARTH BACK TO THE CIRCUIT BOARD V IMPORTANT