"NT" wrote in message
...
On Jul 21, 6:01 pm, John Rumm wrote:
NT wrote:
On Jul 21, 1:33 am, NT wrote:
On Jul 20, 2:57 pm, John Rumm wrote:
NT wrote:
This article could do with input/suggestions:
http://tinyurl.com/mewmhe
or
http://wiki.diyfaq.org.uk/index.php?...trics#Suppleme...

The article is now edited to read
"Unless an installation complies with the latest requirements of the
17th edition... then supplementary equipotential bonding is
required."

Are you saying that there is a requirement to bring all existing
installations into line with this? I'm not aware of any requirement to
do so.

Yes, but I think you are misinterpreting the sense of "required" to mean
something that building regs or some other authority say you must do now.

The "requirement" is a technical one from BS7671. There is no *legal*
obligation to install missing bonding (unless you a changing something
electrical in the room anyway, when one might argue that part P would
make it so).

However, to wire or alter a room containing bath or shower then one
*may* be required (for reasons of complying with BS7671 and for best
practice / good workmanship) to install or upgrade bonding. I use the
word "may" since the 17th edition is the first version in recent times
to offer an alternative to installing bonding.


Sounds like we agree on the principle, but differ on the wording. I
wanted to try and clarify it in the article as its a much
misunderstood area, and many people sent into a tailspin over nothing,
or paying out for work that doesn't need doing.

So in short there is no real world requirement for such bonding to be
retrofitted to existing wiring unless electrical work is being carried
out, in which case the end result should be regs compliant.

I propose adding a sentence to explain that, probably much further up
in the article since it affects most of it.


NT

Hi

The lack of supplementary bonding would be flagged up on a PIR if the wiring
was to the 16th edition. However the lack of RCD protection for cables
behind plaster would also be flagged if the system was installed to the 16th
edition.

The main difference is that the the lack of supplementary bonding would be
code 1 (requires immediate attention) and the lack of RCD protection for the
cables would be code 4 (does not comply with BS17671:2008).

I would suggest that supplementary bonding "when required but not present"
should be installed ASAP regardless of any proposed electrical installation.
As John pointed out, any installations are part P governed and so would need
the supplementary bonding to be installed.

The other point to note is that any alterations to bathroom or kitchen
electrics also need the main equipotential bonding to be brought up to
current standards when the work is carried out.

A mixture of RCD protected and non RCD protected bathroom electrics still
need supplementary bonding. eg a split load 16th edition install with the
bathroom lights non RCD protected and then an electric shower is added to
the RCD side. Supplementary bonding must be fitted between the lighting and
the shower.

HTH

Adam