Upgrade to equipotential bonding proposal

[EastAnglian]

ON an EICR today I observed an installation with two properly connected equipotential bonding cables to gas and water services run correctly to the DB. However these two cables were 6 sqmm, not 10sqmm CSA as now required by the Regs.

Its a period property with wattle & daub walls and the route for the EB cables is a pig to upgrade, requiring a route from ground floor to attic and all sorts of other challenges and disruption.

The gas and water services both rise in the kitchen and are about 1m apart on the same wall. Now, if I cross-bond between both services in the kitchen with a 10sq mm cable then to my simple way of looking at this I will end up with a 'single' 12sqmm bonding cable connecting both services (albeit with a short 10mm 'tail'). The cross-bonding would be equipped with the "safety earth - don't remove" label.

Would you agree this is a pragmatic way to meet the regs?

 

[telectrix]

if the 6mm bonding is sound and shows no sign of deterioration, then it;s fine to be left as is. just a note on the cert. no code.

 

[Deleted member 9648]

Whats the earthing system?....minimum 10mm is only applicable to PME supplies...so may not be relevant if your cottage is TT for example.

 

[EastAnglian]

It was originally a TT system (probably at the time the bonding was installed) but more recently it has been converted to TNC-S

 

[Deleted member 9648]

Well if it's TNCS ....but showing no signs of heat or other deterioration I would go with Tel...but I would code it a C3. Still satisfactory but you need to justify by stating that it does not comply with current Bs 7671 but showing no signs of any deterioration or heat damage.

 

[EastAnglian]

Which indeed is more or less what I have done on the EICR. However, my original question was whether the pragmatic upgrade proposed (which is very straight-forward to achieve!) would enable me to subsequently claim compliance with BS7671:2008 .... thus giving a value-add to my customer.

 

[telectrix]

hmm. going back to orig. post. could you not take one bond off ( whichever is easier ), parallel the 2 6mm's to either the gas or water, sweat/solder/crimp a piece of 10mm from there to the other service. then you would have 2 6mm in true parallel, with a 10mm off. and a continuous bond.

 

[DurhamSparky]

plenty of options...!!!

 

[EastAnglian]

It did occur to me as I typed it up that this was the purest solution, but just not quite so practical!

 

[Engineer54]

hmm. going back to orig. post. could you not take one bond off ( whichever is easier ), parallel the 2 6mm's to either the gas or water, sweat/solder/crimp a piece of 10mm from there to the other service. then you would have 2 6mm in true parallel, with a 10mm off. and a continuous bond.

That would be the solution i would go with, especially as the services are only 1m apart from each other!! Makes perfect sense!!

 

[Adam W]

If it was installed to 16th Edition 6mm is ok, although you need to check for earthed equipotential bonding, ie the whole installation needs to comply to 16th edition.