Supplementary bonding

[jimminick]

Hi there, when fitting a new s/steel kitchen sink and replacing a section of copper pipe with mdpe pipe do we need to supplementary bond between taps and original copper pipe or does the 30mA RCD on the ring main take care of that?

 

[chris gray]

so long as the 30mA rcd covers the power and lighting in the kitchen there would be no requirement to supplementary bond and tbh the fact that the sink is fed with not matallic pipe you wouldnt need to bond it anyway

 

[jimminick]

Many thanks Chris......of course, there will be no path to earth once fitted!

 

[peterlectric]

As a general rule if the plasticpipe is 15 mm and it is more than half a meter in length you would not need to bond

 

[chris gray]

As a general rule if the plasticpipe is 15 mm and it is more than half a meter in length you would not need to bond

whats the pipe diameter got to do with it? if its plastic pipe of any size why would you bond it?
just make sure it is a supplementary bond and not the water bond

 

[Deleted member 9648]

There's no requirement to supplementary bond anything in a kitchen whether or not circuits are RCD'd ,and there never has been.
Supplementary bonding is only required in special locations as defined by bs7671...which does not include kitchens.

 

[pevvers]

There's no requirement to supplementary bond anything in a kitchen whether or not circuits are RCD'd ,and there never has been.

Back in the day I'm pretty sure that there were regs about bonding in kitchens, but I know for a fact that there's been no need to since at least the 16th edition, and definitely not nowadays when you can even omit supp bonding in bathrooms thanks to the all powerful RCD (which of course, never ever ever fail do they, and ALWAYS checked every 3 months )

 

[Sintra]

It is not generally required to supplementary bond the following :
kitchen pipes, sinks, draining boards, metallic kitchen furniture, boiler pipes, metallic parts supplied by plastic pipes or metal pipes to hand basins or wc's ( excluding metal waste pipes in contact with earth ). OSG p31

 

[Deleted member 9648]

I used to spend hours grovelling around under sinks trying in vain to connect a bit of 4.0mm to a tag put in the most awkward place possible...and then the NIC pointed out in a newsletter that there has never in fact been any requirement to bond in kitchens!! As far as I know it arose because of a diagram of a bonded sink in a guide to the regulations.Everyone just assumed it had to be done and the myth was born. It wasnt helped by the sink manufacturers providing an earth tag, and just a few years ago a builder on a job I was on installed a sink packaged in a box with the words printed on...WARNING....THIS PRODUCT MUST BE EARTHED !!....Judging by this thread the myth continues to this day....

 

[Staffie]

The problem is 'joe public' and his best mate who's a 'know all', but knows '*&%$ all'!!!

Phone goes the next day, "my mate said you should have bonded my sink, everybody else's sink appears to be bonded who he know's, apart from mine. Are you sure you're qualified to do this type of work?, I'm not sending you the cheque until it's done....sorry!"

You know how difficult it is explaining this sort of stuff to people, sometimes it's better just to stick a clamp on, smile and go home.....

 

[Deleted member 9648]

You are spot on Staffie,and a phenonema I observed a long time ago is that the advice of the mate...plumber...gardener...bloke down the 'feathers....invariably carries more weight on matters electrical than the electricians.

 

[Scottley]

Sorry to ressurect a thread but i have just had a visit from building control and the building inspector said i have to cross bon the pipework to the basin in my ensuite?

This is a 4 bde 2 bath loft conversion which has been added and a new consumer fitted and all circuits tested by an electrician friend. I cross bonded the megaflow as a matter of course when i ran new earths to the water and gas mains.

I was under the impression that cross bonding in bathrooms was no longer required? The area she is looking at is inside a vanity unit that has no access once the granite top is fitted. I was also under the impression that it had to be visible?

I will bond it all in the eaves space to shut her up mainly but would just like to know 'the truth'

Thanks

Scott

 

[Guest123]

Sorry to ressurect a thread but i have just had a visit from building control and the building inspector said i have to cross bon the pipework to the basin in my ensuite?

This is a 4 bde 2 bath loft conversion which has been added and a new consumer fitted and all circuits tested by an electrician friend. I cross bonded the megaflow as a matter of course when i ran new earths to the water and gas mains.

I was under the impression that cross bonding in bathrooms was no longer required? The area she is looking at is inside a vanity unit that has no access once the granite top is fitted. I was also under the impression that it had to be visible?

I will bond it all in the eaves space to shut her up mainly but would just like to know 'the truth'

Thanks

Scott

As it's BC, I'll give you the answer from the good book, if you have a copy then take it along with you and show her the relevant parts when she is next on site.

Section 701, page 165 of BS 7671 concerns locations containg a bath or shower.

Regulation 701.415.2 covers supplementary bonding in the location and basically it says you must carry it out for any extraneous conductive parts entering the location unless ALL of the following conditions are met.....

1. All main protective bonding (gas, water etc) is present and adequate.

2. All circuits of the location comply with the requirements for automstic disconnection in line with 411.3.2 (essentially in the event of a fault occuring the circuit will disconnect in less than 0.4s which it should if your electrician has tested & inspected it.

3. All the circuits within the location have additional protection via a 30mA RCD (again which they should if your electrician has inspected & tested it).

4. All the pipework within the location is effectively connected to the main protective bonding. There is a calculation for confirming this, ask your electrican to carry out the test and perform the calc for peace of mind if you like.


Sorry if the answer is a bit involved but it is from the book.

Essentially if all the main bonding is in place & there is the 30mA RCD protection to ALL the circuits in the bathroom, supp bonding can be omitted.

 

[Scottley]

Lenny your a genius thanks very much.