Bonding in kitchens and bathrooms?

[GeorginaAnn]

Hello,

I wondered if anyone could help me, I getting a new kitchen which has resulted in a complete re-wire of my house. My father has told me that I should make sure the kitchen and bathroom is bonded, (around the sinks specifically?) but the electrician is telling me this is no longer a requirement. My dad has the 17th edition, I believe of the Electricians guide (2000 is the year it was published) and swears blind this is the case. The electrician has told me there has since been an update and this is no longer required.

Does anyone know if kitchens and/or bathroom should be bonded as a matter of practice or is it just a decision the electrician makes. I live in an ordinary town house whereas my dad is an electrician in Hotels so maybe this is why there is a conflict? Im really not sure does anyone know?

Thank you in advance.

 

[wingcoax]

In the vast majority of cases your electrician is correct. Especially as you have had a rewire. All bonding now is done at scource.

 

[rebuke]

There hasn't been a requirement to do supplementary bonding in a kitchen for a long time, for a bathroom the requirement is still there, but you don't have to do it if (wording of these may not be quite right - I haven't got regs to hand to verify):

1. All circuits in the bathroom are RCD protected
2. Main equipotential bonding is in place
3. You can prove continuity between any exposed metalwork and the MET

Assuming the above are satisfied, then your electrician is right.

 

[Chri5]

BS7671 July 2008...........

Bonding via 10mm earth from gas and water services, plus ADS (rather than EEBADS) means that supplementary bonding isn't required. Although testing of circuits should be used to confirm this.

In non tech language, RCD's or RCBO's cover ADS (auto discon of supply). All circuits after July 2008 should be protected via RCD / RCBO.

There are exceptions, but I'm not going to cover those.

 

[GeorginaAnn]

There hasn't been a requirement to do supplementary bonding in a kitchen for a long time, for a bathroom the requirement is still there, but you don't have to do it if (wording of these may not be quite right - I haven't got regs to hand to verify):

1. All circuits in the bathroom are RCD protected
2. Main equipotential bonding is in place
3. You can prove continuity between any exposed metalwork and the MET

Assuming the above are satisfied, then your electrician is right.

The electrician has stated that there is no need to bond because all the circuits are being protected by RCBO. Therefore nothing in the bathroom is going to be bonded. I was under the impression bonding is still required as we have a metal bath, radiators, and other like items.

What do you mean main equipotential bonding? That implies there should be some bonding in the bathroom? Therefore there should be bonding in the bathroom?

 

[rebuke]

Main equipotential bonding (MEB) is ensuring that there are bonds to things like the incoming gas and water pipes. Bonding things in the bathroom is supplementary bonding, which as I stated is not required as long as the conditions are met.

Basically, as long as you haven't got any plastic pipework between your incoming water pipe and your radiators and bath, then you'll likely have continuity to the MET (your electrician should verify this). The combination of that and the RCD protection means the chances of there existing a potential difference between two conductive parts and that p.d. being able to cause you harm prior to the RCD killing it is tiny...

Having said that, there's nothign wrong with having supplemental bonding if you want it - so you could ask your electrician to put it in anyway if you really want to (though you'd obviously have to pay him more).

 

[securespark]

Yeah, this one often makes me guffaw.

Especially when I see a bad install and the householder tells me the guy was a qualified spark, then when seeking the stopcock to check for PEB's I notice the supplementary 'tween H&C and a neat little flylead up to the sink....

The reg for this work in kitchens was last seen in the 15th Edition (1981-1991).

413-7.

 

[dingbat]

My dad has the 17th edition, I believe of the Electricians guide (2000 is the year it was published) and swears blind this is the case.

... my dad is an electrician in Hotels...

Ah.

I know he's your dad, but that doesn't make him right.

The Seventeenth Edition of the Wiring Regulations was published in 2008, so his guide - which is not an official document - is way out of date.

Any electrician referring to a guide book needs to be aware that authors of such guides are often mistaken and the Regulations themselves should always be consulted.

Your dad is among the vast majority who do not understand earthing and bonding. You electrician may just be in the minority who do understand. (Either way, your dad is wrong.)

 

[dingbat]

(wording of these may not be quite right...):

1. All circuits in the bathroom are RCD protected
2. Main equipotential bonding is in place
3. You can prove continuity between any exposed metalwork and the MET

Not quite right. Paraphrasing:
1. Correct
2. All circuits meet disconnection times
3. Extraneous parts are effectively connected to main bonding.

Your understanding of the third point is incorrect - if there are plastic inserts in the pipework then you almost certainly do not have extraneous parts in the bathroom, so bonding would not be required anyway. That is; plastic pipes - no need to bond, metallic pipes - no need for supplementary bonding if main bonding is correctly installed, if necessary. (Of course, some checks - by measurement - should be made to confirm the actual circumstances.)

And, by the way, there is no such thing as 'supplemental' bonding.