Supplementary Bonding (yes, I can hear you all groaning!)

[spooky_b329]

First things first, I have searched for this and am unable to find the answer!

In my bathroom I have pull switch, light fitting, radiator and bath. I believe I should bond between pull switch, bath and radiator?

My radiator pipes go into the concrete floor and do not reappear until 5 metres away on the other side of my kitchen, should I chase out the bathroom wall from ceiling to floor to run the earth to the rad or can I run the supplementary bonding back through the kitchen ceiling and connect to the CH pipes feeding the bathroom under a wooden floor? The bath is opposite the radiator with no easy path to bond directly between them.

Also, can I bond bath and radiator via the light fitting or should it go back to the pull switch? Or should all four points be bonded?

Thanks for any help

Edit: My pull switch is outside the various zones (just) so I assume I can bond the other stuff via the light fitting?

 

[comms]

or can I run the supplementary bonding back through the kitchen ceiling and connect to the CH pipes feeding the bathroom under a wooden floor?

You can.

The bath is opposite the radiator with no easy path to bond directly between them

Is there an airing cupboard local to the bathroom thats easier to get to, if so do all your bonding there.

can I bond bath and radiator via the light fitting or should it go back to the pull switch?

either (so long as there is a cpc between switch & fitting).

 

[spooky_b329]

Thanks for the reply

The kitchen route is now looking less appealing as I'd also have to chase out a route down from the ceiling, which would have been a lot easier last week before I dot 'n dabbed plasterboard to the wall!

Unfortunately the bathroom is downstairs whilst the airing cupboard is upstairs in the main part of the house.

There is a CPC between pull switch and fitting, so could I bond from there to the H&Cold pipes under the bath, then use the pipes as the earth path back into the main house where I could then bond from them back to the central heating that leads back into the bathroom?

Also, if I happened to want a shaver point at a later date, would the CPC back to the light feed be sufficient or would it require its own bonding?

Thanks

 

[sparkybird]

You need to bond between hot/cold/rad/bath and any circuits in the bathroom. The bonding must be continuous ie you can't use the pipe as the bonding conductor. Under NIC rules, IIRC, if the boiler is located in the adjacent room to the bathroom (eg above it?) then you could bond there.

If you shaver is on the existing (bonded) lighting circuit, I would suggest that you don't need to bond to it

Under the new 17th edition regs you could put the lighting circuit on and rcd/rcbo and forget about the bonding...

 

[JohnD]

...The bonding must be continuous ie you can't use the pipe as the bonding conductor..

sure?

 

[spooky_b329]

Sparky - you say in the new regs that I just need to RCD it and that would remove the need for any bonding. When does that come into effect? Looks like I'm going to have to detroy a ceiling otherwise!

 

[spooky_b329]

I was looking at this earlier which seems to suggest I can use the pipes, but obviously I'm not sure how far from the bathroom you can go before bonding is not allowed.

http://www.iee.org/Publish/WireRegs/EarthingPlasticPipes.pdf Page 3, metal pipes.

 

[Qedelec]

17th edition came in on jan 1st.

 

[spooky_b329]

So I can forget all this bonding stuff and just make sure my lighting is RCD'd at the CU?

Does this mean I don't need to earth the bathroom pipes directly back to the CU as well? Rising main is earthed.

 

[GaryMo]

So I can forget all this bonding stuff and just make sure my lighting is RCD'd at the CU?

As long as the installation was designed to, complies with and is certified to BS7671:2008.

 

[flyingsparks]

17th edition came in on jan 1st.

I thought 17th comes in in june or july??

 

[GaryMo]

17th edition came in on jan 1st.

I thought 17th comes in in june or july??

The first six months is an overlap period where you can choose to be proactive. Come 1st July we have no choice though.

 

[comms]

So I can forget all this bonding stuff and just make sure my lighting is RCD'd at the CU?

Does this mean I don't need to earth the bathroom pipes directly back to the CU as well? Rising main is earthed.

There are other requirements that need to be met for you to be able to go down this route.
(i) all final circuits in the location comply with requirements for automatic dissconnection ref reg 411.3.2

(ii) all final circuits of the location have additional protection by means of rcd ref reg 701.411.3.3

(iii) all extraneouse conductive parts of the location are effectively connected to the protective equipotential bonding according to regulation 411.3.1.2

The bonding must be continuous

Think youre on about equipotential bonding here sparkybird.

you can't use the pipe as the bonding conductor

I've not got the 16th ed to hand (it's out in the van)but you might want to check SB
I do however have the 17th here
544.2.4 (doesnt say pipes but does say "a conductive part of a permanent & reliable nature, or by a combination of these")
You could even use 543.2.6 at a push.

If you shaver is on the existing (bonded) lighting circuit, I would suggest that you don't need to bond to it

I'd second that.

 

[ban-all-sheds]

Does this mean I don't need to earth the bathroom pipes directly back to the CU as well?

You never did have to.

Supplementary Equipotential Bonding is not the same as earthing....

 

[spooky_b329]

Thanks...just wanted to check as once I've sorted out my kitchen I won't be able to run any more cables to the bathroom!

Better safe than sorry