Earthing Copper Pipe

[DIYC]

Guys,

I've been making some changes to the plumbing in my bathroom and now I need some advice about earthing.

The following diagram shows the result of the changes I've made.

The copper top left is the original pipe and goes to the ensuite bathroom (next door).

The copper at the bottom is the original pipe and goes into the airing cupboard.

The copper top right is a tiny (6 inch) piece of 15mm copper pipe that I've used to join a HEP20 elbow to to flexi tap connector.

The bit in the middle is plastic HEP20 pipe (which is new - it all used to be copper).

My question is this, I've obviously broken what would have been a circuit.
There's no sign of any earthing straps on the copper that remains.
Do I need to earth the 6 inch of copper pipe that leads to the toilet (top right) or is that small enough to be insignificant?

Do I need to earth anything else?
I'm assuming you don't need to earth the new plastic pipe?
Is it best to earth the other copper pipe (I can see)?
How? (Do I just bridge the plastic pipe with some earth cable?).

Any advice would be really appreciated, thanks.

C.

 

[sparkyspike]

Don't worry about the plastic pipe. The main thing is to ensure that a) the hot and cold taps are cross-bonded (i.e a clamp on each copper tail leading to the taps connected with cable) b) exposed metal such as radiators, towel rails and metal waste pipe are bonded to any electrical accesories such as light switch or shaver point. The purpose is to ensure that all metal surfaces are at the same voltage if there is a fault. c) Is there any earthing already done in your bathroom?

 

[ColJack]

shame on you spike..

all pipework must be bonded to ensure continuous earth..

put an earthclamp on each piece of pipe and run a 6mm earth wire round to each and back to the rest of the bonding..

 

[davy_owen_88]

Actually, you don't need to do anything even to the small lengths of copper pipe. Anything supplied by plastic does not require bonding.

For plastic pipe installations within a bathroom the plastic pipes do not require supplementary bonding and metal fitments attached to these plastic pipes also would not require supplementary bonding.

It seems to be the practice of some builders to effect all the plumbing in plastic except for those bits of the pipework that are visible. These short lengths of metal pipework supplied by plastic pipes or metal taps connected to plastic pipes, metal baths supplied by plastic pipes and with a plastic waste do not require supplementary bonding.

However, electrical equipment still does require to be supplementary bonded and if an electric shower, or radiant heater is fitted, they will require to be supplementary bonded as usual.

http://www.iee.org/Publish/WireRegs...tumn_plastic_pipes_to_bond_or_not_to_bond.pdf

 

[ricicle]

shame on you spike..

run a 6mm earth wire round to each and back to the rest of the bonding..

4 mm² is fine as an unprotected SEBC

 

[ColJack]

doesn't that apply only to bathrooms where the fittings are supplied in it's entirity by plastic?

the copper pipes entering the room introduce a potential that is different than earth if not bonded..

if the pipes are not accessible then there should be no problem..

I would however still bond the pipe from the airing cupboard ( I assume there is an immersion in there or something? ) and the pipe feeding the en-suite next door just to be on the safe side..

while it may not be a requirement, it is also not expressly forbidden..

what is the cost of a few meters of wire and a few earth clamps compared to any potential risk?

 

[sparkyspike]

 

[sparkyspike]

shame on you spike..

all pipework must be bonded to ensure continuous earth..
..

Supplementary bonding is not required to metal parts supplied by plastic pipes. This is why I emphasized instead the need to bond electrical equipment in the zones. You should also ensure before doing anything, that your main bond has been done.

 

[Spark123]

Just supplied by a plastic pipe isn't really good enough, it needs to be supplied by enough plastic pipe taking into account the medium inside to provide adequate insulation as so the conductive part i.e. a radiator can not introduce a path for a enough current to flow to cause danger.

 

[DIYC]

Guys, thanks for taking the time to repy, however, I'm a little confused so here is what I plan to do...

1, cross bond the 2 copper pipes from the airing cupboard (hot and cold)
2, cross bond the 2 copper pipes to the ensuite (hot and cold)
3, connect the 2 cross bonding clamps with the earth cable in some T&E.
4, cross bond the tap tails for the sink (hot and cold)
5, connect the cross bonding clamp on the sink tap tails to the cross bonding clamp on the ensuite feeds using the earth cable in T&E.
5, do nothing to the flexi tap connector to the toilet
6, do nothing to the plastic pipe

I'm not really fussed if this is overkill, it's not going to send the project significantly more over budget than it already is!

Please correct me though if what I'm proposing does not serve the intended purpose.

Many thanks.

 

[dingbat]

Test, test, test.

In particular you need to verify whether or not any pipework satisfies the whole of the definition of an 'extraneous conductive part', especially the bit about introducing a potential, generally earth potential...

You need to measure the resistance between any such parts and the main earthing terminal; anything over 22,000 Ohms is considered to be electrically isolated from earth and does not need to be bonded.

Sadly, if this means nothing to you, there's a fair chance it will not mean much more to your average domestic electrician, to whom the subject of Earthing & Bonding (excellent new Guidance Note 8, by the way, fellas) is, in my experience, a subject of myth and mystery.

 

[dingbat]

put an earthclamp on each piece of pipe and run a 6mm earth wire round to each and back to the rest of the bonding..

It is potentially dangerous to bond indiscriminately... especially when working to the guidance of an edition of the regulations now sixteen years out of date!

 

[sparkyspike]

put an earthclamp on each piece of pipe and run a 6mm earth wire round to each and back to the rest of the bonding..

Would you also run 6mm cable around every compression joint where PTFE tape has been used?!

 

[Spark123]

(excellent new Guidance Note 8, by the way, fellas)

You got it? Mine is on order from Amazon as we speak.

 

[dingbat]

Amazon? I have a direct line to the the IET.