Invisible Bonding of hot & cold pipes

[zybbok]

Hello folks.
I’m replacing the original 3 toilets, bath and mixer shower in the house.
Everything that needs to be done is all plumbing work; no electrics at all.
As usual the originals were just thrown together during the building of the house about 12 years ago and I want the new installation to be as neat as possible.
As I’m lifting the floorboards (chipboard) I’m wondering if it’s possible and legal to put the bonding of the Hot & Cold water pipes under the floorboards to make it invisible.
Thanx in advance.

 

[ebee]

Main bonding - connecting of electrical installation earth to gas/water/oil/structural metal etc should ideallybe done via clamps/connections that are visible in order that their presence and effectiveness can be verified from time to time.

That's not usually a great problem.

Supplementary bonding, say in a bathroom for instance, again it would be ideal if it can all be verified easily but this might make it unsightly but with care you might be able to make it hidden from immediate view and therefore more pleasing to the eye. It can be hidden, if permanent ie a soldered joint rather than a clamp or screw but of course this would mean any pipes are empty of water etc at the time of soldering. Hot, cold & heating system pipes in such locations (or very near to them) should be bonded together and also to the earth terminals of any circuit of the location.

Under the 17th Edition of the regs then supplementary bonding may be relaxed, providing ALL (yes ALL) of the conditions to do so are met. RCDs on every circuit of the location, main bonding in place and electrical continuity of the pipework to pipework that is main bonded.

If like me, you feel that such reliance on the RCD (failure rate 7%ish ?) and the reliance that an insulating piece of pipework is not added at a later date does not justify it then you might still decide to supplementary bond anyway.

 

[dingbat]

Under the 17th Edition of the regs then supplementary bonding may be relaxed, providing ALL (yes ALL) of the conditions to do so are met. RCDs on every circuit of the location, main bonding in place and electrical continuity of the pipework to pipework that is main bonded.

No. The bit I underlined is incorrect, ebee.

 

[ebee]

you are correct, that statement is incorrect in that it applies only if the pipework in the bathroom is an extraneous conductive part in that it must be connected to the main protective bonding (either by continuity or by connecting a bonding cable I would say)


If it is not an extraneous conductive part then it need not be connected to the main protective bonding, in fact to do so could reduce safety below that which already exists