On 04 Jan 2009 16:21:18 GMT, (Andrew
Gabriel) wrote:

That's the service bonding.
Nowadays, it should be 10mm², IIRC.

I remember the electrician who checked the electrics before we moved
in said something about the earthing not being to the latest regs. I
can't remember if it is 4 mm^2 or 6mm^2, I guess I'll have to measure
the diameter of the wire and calculated the area to see. He said it
ought to be 10mm^2 to comply with the regs but he thought it was safe
nonetheless. Is it worth upgrading it to 10mm^2?

In my last house the (gas) boiler had all the pipes cross bonded
immediately beneath it. None of the pipes going to or from this boiler
are. I don't think the CH pipes are earthed anywhere. Should they be?

They probably are in or adjacent to the bathroom -- that's where it's
normally done.

You are quite right. I've just looked; behind the pedestal and under
the bath, all out of sight, the bath, basin, and bathroom radiators
are bonded.