In article ,
"Jim" writes:
Hi guys

Still looking at getting my boiler and HW cylinder replaced, so far managed
to get 2 quotes out of the 4 plumbers that have visited!

Plumber A has specifically stated that the gas meter and water mains will
need to be earthed and plumber B has put a caveat in his quote that it
excludes any cross bonding that may be necessary to meet IEE Regs. Could
some kind sole confirm or correct me on the following

1. House is 30+ years old and I can't see any obvious earth wire in the
vicinity of the gas meter so it is likely that appropriate earthing will be
necessary

2. Is this simply a case of running a cable from the CU and clamping to the
outlet of the gas meter (and from there to the water mains)

Yes, but also checking that the main earth is satisfactory and working.
Avoid cutting the conductors in the case where they continue on from
one clamp to further clamps -- just strip the insulation so you can
connect to the unbroken conductor.

3. What size cable should be used for this

10mm² usually.

4. Does it have to be done by an electrician or could I do it myself (I'm
reasonably competant - replaced the CU, installed burglar alarm etc)

Sounds like you are either competent yourself, or there's much
more to worry about in the CU you already installed;-)

5. Any problems with running the cable under the carpet around the edge of
the room on solid concrete floor.

Not a good idea -- it could get damaged without being noticed.

--
Andrew Gabriel