Supplementary Bonding Question

[Dairyspark]

Hi again guys , question about bonding doing a kitchen for a colleague and the only bit I lack knowledge in is bonding requirements. He has a main 10mm2 bond to his water service and one to his gas which is fine, now his cold water feed is going from copper (main pipe) to plastic to supply kitchen items then back to original copper for bathroom, and same idea with his hot water, now my question is will I need to attach supplementary bonding to these pipes or am I just a numpty?

Cheers

Bobby

 

[binky]

how long is the 'plastic break'?

over 1m then unlikely to be required, contrary to popular belief water is a poor conductor of electricity. Only way to be sure is to do a continuity check between water /gas incoming point and pipework other side of palstic sections, but beware of parallel earth paths - disconnect all other earths at board to ensure a suitable test

 

[Dairyspark]

About a meter for both hot and cold

 

[Rob_the_rich]

do the pipes in the bathroom go down into a concrete floor?

 

[Andy™]

test to see if its extraneous. if yes, bond it, if not, leave it

there can be cases where the entire inside is copper fed from plastic, and you dont need to bond anything

 

[Dairyspark]

No they stop in the bathroom, that's the end of line so to speak, the main line comes in to his kitchen, up the wall a feeds 2 upstair flats as well, and how do I go about testing if it's extraneous?

 

[binky]

with the increasing use of platic pipe this is an increasingly common problem, but if incomers are bonded most issues are illiminated - do some reading of regs

need a 'wander lead'

 

[Rob_the_rich]

test to see if its extraneous. if yes, bond it, if not, leave it

there can be cases where the entire inside is copper fed from plastic, and you dont need to bond anything

There are plastic sleeved metal gas supply pipes which look like plastic pipes, they are usually straight though. If in doubt...

 

[Andy™]

No they stop in the bathroom, that's the end of line so to speak, the main line comes in to his kitchen, up the wall a feeds 2 upstair flats as well, and how do I go about testing if it's extraneous?

22k test

 

[Dairyspark]

searching the regs now and Andy, please excuse my little knowledge but what's a 22k test?

 

[binky]

if its over 22k ohms it doesn't need supplemenatary bonding. How many RCDs on the circuits?

 

[Dairyspark]

Currently none, but when the new kitchen gets connected there will be an rcbo for the sockets in the kitchen, if that's not sufficient then please let me know

 

[binky]

it is sufficient for what you are modifying,(what about lights) but leaves bonding issues as the property will be covered by old and new regs. How old are the electrics?

 

[Dairyspark]

I'll ask him tomorrow at work and I'll get back to you and the kitchen is part of the living room so the light switch is at the living room door, approx. 16ft away

 

[binky]

are you altering the light cct?

 

[Dairyspark]

Changing the light switch to a dimmer and new light fittings but the wiring will stay the same, only work im doing is extending the ring circuit to 4 sockets and a 4 grid switch for under counter sockets for washing machine etc.

 

[pewter]

i thought it only needs supplementary if circuits do not have RCD protection,

I would take that as any circuits that might be affected by a potential water leak from the bathroom area (above + below), should have RCD, if not bond it.

Just using a vague memory of the regs and my own opinion.

I then sat back and had to look in the book.  701.415.2.

Sad

 

[Dairyspark]

That the one about all 3 conditions must be me?

 

[pewter]

i take reg  to mean if you dont meet the 3 conditions you need you need the bonding.

 

[binky]

pretty much pewter, RCD everything, main bond gas and water in 10mm, check main earth is 16mm and 99% of houses comply with regs.