In message , Andy Wade
writes
Chris J Dixon wrote:
So far as I can see, it is quite OK for the underfloor bonding
and the ceiling bonding to be joined only by a common length of
pipe. Is this right?

Debatable. Reg 547-03-04 allows conductive parts "of a permanent and
reliable nature" to be used as part of the bonding. If you think a
plumber could come along and replace the pipework in question with
plastic and not realise that any bonding would need to be patched then,
IMO, that regulation couldn't be applied. (IOW, if in doubt, bond
separately.)

HTH

In a sense this is a slight extension of Fig 4d in the OSG - several
separate supplementary bonds taken back to the plumbing - which ties
everything together. So say your cold riser from underfloor up into the
loft _could_ be used as the path to link lighting circuit bonding to the
rest, subject to the proviso as above that its unlikely to be replaced
without Joe Plumber getting sufficient clue that the bonding was at both
ends of it. So if the earth clamps are well away from the vertical run,
then not a good idea, but if the clamps are say just above the ceiling
at the top, and at say floor level in the airing cupboard, then I
wouldn't see a problem.



--
Steve