Sorry but I'm sure it must be *hours* since we last had one!

I'm currently applying the bonding to an all-copper plumbed bathroom.
It's going to have a separate self-contained shower cubicle (still
awaiting delivery of that) with its pipework emerging from within a stud
partition.

Now, practically speaking I would apply bonding clamps to the shower's
H&C pipes where they emerge from the wall, however they will be
concealed behind the shower paneling once I've installed it. Therefore,
how will the bathroom pass its electrical inspection, if the inspector
can't see the clamps?

The shower pipes themselves travel down below the bathroom floor and
emerge again at the bath taps, where there will be another couple of
clamps. In theory, I understand that I shoudn't need to bond at every
tap in the room (I'm doing the basin and toilet feed too), as the copper
pipe will do the job - but as the inspector won't be able to see it all,
will he accept that there's no plastic pipes anywhere?

Separate issue - also in the bathroom is a white-painted towel rail,
connected to the CH via 10mm copper tubing. The picture in the OSG just
vaguely shows the bathroom rad being bonded, without details... Do I
need to fit clamps to both supply and feed pipes (and not the towel rail
itself - don't know where I'd fit one anyway?)

Thanks
David

On 17/02/2007 14:50, Lobster wrote:

how will the bathroom pass its electrical inspection, if the inspector
can't see the clamps?

By looking at the photos you take of them before boxing them in?

On Sat, 17 Feb 2007 14:50:51 GMT, Lobster
mused:

Sorry but I'm sure it must be *hours* since we last had one!

I'm currently applying the bonding to an all-copper plumbed bathroom.
It's going to have a separate self-contained shower cubicle (still
awaiting delivery of that) with its pipework emerging from within a stud
partition.

Now, practically speaking I would apply bonding clamps to the shower's
H&C pipes where they emerge from the wall, however they will be
concealed behind the shower paneling once I've installed it. Therefore,
how will the bathroom pass its electrical inspection, if the inspector
can't see the clamps?

The shower pipes themselves travel down below the bathroom floor and
emerge again at the bath taps, where there will be another couple of
clamps. In theory, I understand that I shoudn't need to bond at every
tap in the room (I'm doing the basin and toilet feed too), as the copper
pipe will do the job - but as the inspector won't be able to see it all,
will he accept that there's no plastic pipes anywhere?

Intermediate inspection or he'll just have to believe you.

Separate issue - also in the bathroom is a white-painted towel rail,
connected to the CH via 10mm copper tubing. The picture in the OSG just
vaguely shows the bathroom rad being bonded, without details... Do I
need to fit clamps to both supply and feed pipes (and not the towel rail
itself - don't know where I'd fit one anyway?)

Who knows, should be fine but depends on the inspector and this weeks
revision to acceptable practices.
--
Regards,
Stuart.

The Inspector could always give it a **category 5 classification** ie

'.....does not comply with current regulations but give it a few weeks
and
it probably will when they next decide to change their minds about how
things should / should not be done....'


--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG

On Sat, 17 Feb 2007 14:50:51 GMT someone who may be Lobster
wrote this:-

Separate issue - also in the bathroom is a white-painted towel rail,
connected to the CH via 10mm copper tubing. The picture in the OSG just
vaguely shows the bathroom rad being bonded, without details... Do I
need to fit clamps to both supply and feed pipes (and not the towel rail
itself - don't know where I'd fit one anyway?)

Does the towel rail have an electric element?

If it does then it must be bonded as it is part of the electrical
system. Assuming that the cord to the element is short and unlikely
to be damaged then this can be done by running the bonding cable
just to the cord outlet and connecting it to the protective
conductor there. The protective conductor in the cord is considered
enough (personally I don't like this, but the IEE/IET disagree).

If it does not have an electric element then, assuming all of it is
visible, it is unlikely to introduce a potential into the area (just
like a radiator, metal window frame or the bit of chain the plug
hangs from). However, the pipes to it may introduce a potential (for
example an electric cable may be lying on a pipe and the insulation
may then melt slowly) so the flow and return pipes should be locally
bonded. This only needs to be done once in the bathroom (or nearby)
assuming that the pipes are joined by reliable metal to metal
contact. Assuming you use proper joints this will actually bond the
towel rail as well.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

"Lobster" wrote in message
...
Sorry but I'm sure it must be *hours* since we last had one!


Separate issue - also in the bathroom is a white-painted towel rail,
connected to the CH via 10mm copper tubing. The picture in the OSG just
vaguely shows the bathroom rad being bonded, without details... Do I need
to fit clamps to both supply and feed pipes (and not the towel rail
itself - don't know where I'd fit one anyway?)

Thanks
David

Snag 33 of the NICEICs "earthing snags and solutions" suggests that you can
make the bonding connection out of site by soldering the supplementary
bonding cable to the flow and return pipes just below the floorboards as
this would be a permant connection and inspection would not be required.

Adam

Owain wrote:
Lobster wrote:
I'm currently applying the bonding to an all-copper plumbed bathroom.
It's going to have a separate self-contained shower cubicle (still
awaiting delivery of that) with its pipework emerging from within a
stud partition.
Now, practically speaking I would apply bonding clamps to the shower's
H&C pipes where they emerge from the wall, however they will be
concealed behind the shower paneling once I've installed it.
Therefore, how will the bathroom pass its electrical inspection, if
the inspector can't see the clamps?

Photos are one idea, but screw terminals in general aren't acceptable if
they're inaccessible.

The shower pipes themselves travel down below the bathroom floor and
emerge again at the bath taps, where there will be another couple of
clamps. In theory, I understand that I shoudn't need to bond at every
tap in the room (I'm doing the basin and toilet feed too), as the
copper pipe will do the job - but as the inspector won't be able to
see it all, will he accept that there's no plastic pipes anywhere?

Ideally you need to bond close to where the shower pipes enter the
bathroom - can you get a bond at the opther side of the stud wall, or in
the loft above or floor void of an adjacent room?

Thanks for all the very helpful replies.

The shower pipes travel down from the bathroom taps (which will be
bonded there), under the floorboards, along the length of the bathtub
and then up into the stud partition behind where the shower unit will
stand (ie at the foot of the bath). So I suppose when the bath panel is
off, I can ensure the two pipes will be visible through a gap in the
floor boards, disappearing under the shower. I could bond there I
suppose? But probably overkill anyway given that it's all obviously
copper? AIUI providing the inspector is convinced of the integrity of
copper between shower, bath, basin and sink, then a single H-C strap
would actually be all that's required for the H and C pipework? (and
linked to the towel rail).

David











IMHO if the pipes are bonded where they enter the room at the shower
they don't need to be bonded again at the basin /provided/ they don't
leave the equipotential zone. If the pipes do leave the equipotential
zone then they do need to be bonded again at the basin. It's up to you
whether you consider 'below the bathroom floor' to be within or outwith
the equi. zone.

If you had 1m of plastic pipe at the edge of the equi. zone the basin
wouldn't need bonding anyway, because plastic pipe isn't considered to
be a risk of introducing a potential.

Separate issue - also in the bathroom is a white-painted towel rail,
connected to the CH via 10mm copper tubing. The picture in the OSG
just vaguely shows the bathroom rad being bonded, without details...
Do I need to fit clamps to both supply and feed pipes (and not the
towel rail itself - don't know where I'd fit one anyway?)

IMHO yes at the supply pipes as that is where the potential may be
introduced (and join that up to all the other bonding, and then the cpc
of the lighing circuit etc. I've seen a lot of bonding where the sparky
things "green wire between hot and cold taps and the job's a good'un")

Owain

On Sun, 18 Feb 2007 13:48:23 GMT someone who may be Lobster
wrote this:-

The shower pipes travel down from the bathroom taps (which will be
bonded there), under the floorboards, along the length of the bathtub
and then up into the stud partition behind where the shower unit will
stand (ie at the foot of the bath). So I suppose when the bath panel is
off, I can ensure the two pipes will be visible through a gap in the
floor boards, disappearing under the shower. I could bond there I
suppose?

You could do.

Why not run the pipes under the bath, rather than under the floor?

But probably overkill anyway given that it's all obviously
copper?

Provided you have proper joints, soldered or compression, then the
copper pipes will probably have higher electrical conductivity than
a bonding cable. However, some people do want to see bonding near
taps and showers, even if a metal pipe is doing the job better.

AIUI providing the inspector is convinced of the integrity of
copper between shower, bath, basin and sink, then a single H-C strap
would actually be all that's required for the H and C pipework? (and
linked to the towel rail).

You also need to connect the bonding cable to the protective
conductors of all circuits feeding equipment in zones 1, 2 and 3.
This is likely to mean connecting to at least the lighting circuit,
though the connection can be made at a suitable junction box near to
the bathroom.

I take it that the bath and shower tray are not metallic.

I take it that you have also selected appropriate
equipment/switchgear and the wiring system complies with what can be
in which zone.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Sun, 18 Feb 2007 13:48:23 GMT someone who may be Lobster
wrote this:-

Why not run the pipes under the bath, rather than under the floor?

Well if they weren't already run, I would probably have done so with
this issue in mind (but it seemed easier at the time just to put them
under the floor out of the way - and the joists run parallel with the
bath and all the floorboards were up).

You also need to connect the bonding cable to the protective
conductors of all circuits feeding equipment in zones 1, 2 and 3.
This is likely to mean connecting to at least the lighting circuit,
though the connection can be made at a suitable junction box near to
the bathroom.

Well, the bathroom electrics are restricted to SELV halogens in the
ceiling and a 240V timer fan in the wall (all in Zone 3) wired to a
switch on the landing, so my understanding is that I shouldn't be
bonding to the cpc of the lighting circuit, right?

I take it that you have also selected appropriate
equipment/switchgear and the wiring system complies with what can be
in which zone.

I take it that the bath and shower tray are not metallic.

Bath is in metal fact, and that will be bonded to its H&C taps.

Thanks
David

On Sun, 18 Feb 2007 18:07:30 GMT someone who may be Lobster
wrote this:-

Well, the bathroom electrics are restricted to SELV halogens in the
ceiling and a 240V timer fan in the wall (all in Zone 3) wired to a
switch on the landing, so my understanding is that I shouldn't be
bonding to the cpc of the lighting circuit, right?

Which circuit is the fan powered by?

Bath is in metal fact, and that will be bonded to its H&C taps.

Are they connected by reliable metal to metal contact to the bath
itself? Probably not, due to washers. If there is not a suitable
bonding point on the bath then a hole can usually be tapped into a
suitable bit of the bath.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Sun, 18 Feb 2007 18:07:30 GMT someone who may be Lobster
wrote this:-

Well, the bathroom electrics are restricted to SELV halogens in the
ceiling and a 240V timer fan in the wall (all in Zone 3) wired to a
switch on the landing, so my understanding is that I shouldn't be
bonding to the cpc of the lighting circuit, right?

Which circuit is the fan powered by?

The lighting circuit.

Bath is in metal fact, and that will be bonded to its H&C taps.

Are they connected by reliable metal to metal contact to the bath
itself? Probably not, due to washers. If there is not a suitable
bonding point on the bath then a hole can usually be tapped into a
suitable bit of the bath.

Bath has a welded-on tag for the purpose, from which I've scraped away
the enamel around the hole in the tag for the reason you describe.

David

On 18 Feb, 09:36, "ARWadsworth"
wrote:
"Lobster" wrote in message
//snip//
Snag 33 of the NICEICs "earthing snags and solutions"

can you give the source for this document/information please?


TIA

"jim" wrote in message
ups.com...
On 18 Feb, 09:36, "ARWadsworth"
wrote:
"Lobster" wrote in message
//snip//
Snag 33 of the NICEICs "earthing snags and solutions"

can you give the source for this document/information please?


TIA

http://www.tlc-direct.co.uk/Products/BKSNA1.html

http://www.amazon.co.uk/Snags-Solutions-Electrical-Incorporating-Requirements/dp/0953105873

Sorry, there is no online version.

Adam

On Sun, 18 Feb 2007 23:16:15 GMT someone who may be Lobster
wrote this:-

Well, the bathroom electrics are restricted to SELV halogens in the
ceiling and a 240V timer fan in the wall (all in Zone 3) wired to a
switch on the landing, so my understanding is that I shouldn't be
bonding to the cpc of the lighting circuit, right?

Which circuit is the fan powered by?

The lighting circuit.

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Sun, 18 Feb 2007 23:16:15 GMT someone who may be Lobster
wrote this:-

Well, the bathroom electrics are restricted to SELV halogens in the
ceiling and a 240V timer fan in the wall (all in Zone 3) wired to a
switch on the landing, so my understanding is that I shouldn't be
bonding to the cpc of the lighting circuit, right?
Which circuit is the fan powered by?
The lighting circuit.

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.

Really...? wow. I've had several bathrooms signed off by sparks in the
past and that's never been an issue. Anyway, better to find out now
rather than in a few days, after the plasterer's been...!

David

On Mon, 19 Feb 2007 07:49:41 GMT someone who may be Lobster
wrote this:-

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.

Really...? wow. I've had several bathrooms signed off by sparks in the
past and that's never been an issue. Anyway, better to find out now
rather than in a few days, after the plasterer's been...!

Amendment No 3, April 2000, is presumably still available for
download. 601-04-01.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Mon, 19 Feb 2007 07:49:41 GMT someone who may be Lobster
wrote this:-

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.
Really...? wow. I've had several bathrooms signed off by sparks in the
past and that's never been an issue. Anyway, better to find out now
rather than in a few days, after the plasterer's been...!

Amendment No 3, April 2000, is presumably still available for
download. 601-04-01.

Thanks - new cable duly run, painlessly. I'm glad you raised this!
I'll have to educate my sparks on the subject. No, maybe not. (He also
insists I supplementary bond the kitchen: I don't argue....

Out of interest though... I'm struggling to work out how either the
bathroom or the double-insulated fan up in Zone 3 can possibly be made
safer by connecting in the cpc of the fan's circuit to the bathroom's
supplementary bonding. In what scenario would it help?

David

"Lobster" wrote in message
...
David Hansen wrote:
On Mon, 19 Feb 2007 07:49:41 GMT someone who may be Lobster
wrote this:-

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.
Really...? wow. I've had several bathrooms signed off by sparks in the
past and that's never been an issue. Anyway, better to find out now
rather than in a few days, after the plasterer's been...!

Amendment No 3, April 2000, is presumably still available for
download. 601-04-01.

Thanks - new cable duly run, painlessly. I'm glad you raised this! I'll
have to educate my sparks on the subject. No, maybe not. (He also insists
I supplementary bond the kitchen: I don't argue....

Out of interest though... I'm struggling to work out how either the
bathroom or the double-insulated fan up in Zone 3 can possibly be made
safer by connecting in the cpc of the fan's circuit to the bathroom's
supplementary bonding. In what scenario would it help?


It is there in case the fan is changed to a class I fan. Not very likey I
know. The real reason is mainly for the lights. Imagine when SWMBO wants to
change the SELV halogens to a 230V class I fitting in a few years time. If
the 230V cpc of the lighting is already supplementary bonded you have no
extra work to do when you remove it.

Adam

ARWadsworth wrote:

It is there in case the fan is changed to a class I fan. Not very likey
I know. The real reason is mainly for the lights. Imagine when SWMBO
wants to change the SELV halogens to a 230V class I fitting in a few
years time.

In a few years time (not much more than one year, in fact) the 17th
edition will be in force and she'll have the alternative option of
putting the lights on an RCD. If all circuits feeding stuff in the
bathroom are 30 mA RCD'd and the main bonding is present & correct then
no supplementary bonding will be required in the bathroom. At the same
time she'll be able to install a 13 A socket or two, provided the room's
big enough... (sockets must be at least 3 m horizontally from the edge
of zone 1.

--
Andy

On Mon, 19 Feb 2007 18:57:27 +0000, Andy Wade
mused:

In a few years time (not much more than one year, in fact) the 17th
edition will be in force and she'll have the alternative option of
putting the lights on an RCD. If all circuits feeding stuff in the
bathroom are 30 mA RCD'd and the main bonding is present & correct then
no supplementary bonding will be required in the bathroom.

Now that will be handy, my house (being the house that a sparks
resides in) has no supplementary bonding to speak of!
--
Regards,
Stuart.

ARWadsworth wrote:

"Lobster" wrote in message
...
David Hansen wrote:
On Mon, 19 Feb 2007 07:49:41 GMT someone who may be Lobster
wrote this:-

Whether the fan is of Class I or Class II construction the
protective conductor of the fan circuit must be connected to the
bonding.
Really...? wow. I've had several bathrooms signed off by sparks in
the past and that's never been an issue. Anyway, better to find out
now rather than in a few days, after the plasterer's been...!

Amendment No 3, April 2000, is presumably still available for
download. 601-04-01.

Thanks - new cable duly run, painlessly. I'm glad you raised this!
I'll have to educate my sparks on the subject. No, maybe not. (He
also insists I supplementary bond the kitchen: I don't argue....

Out of interest though... I'm struggling to work out how either the
bathroom or the double-insulated fan up in Zone 3 can possibly be made
safer by connecting in the cpc of the fan's circuit to the bathroom's
supplementary bonding. In what scenario would it help?

It is there in case the fan is changed to a class I fan. Not very likey
I know. The real reason is mainly for the lights. Imagine when SWMBO
wants to change the SELV halogens to a 230V class I fitting in a few
years time. If the 230V cpc of the lighting is already supplementary
bonded you have no extra work to do when you remove it.

Ah, OK.

But I thought it *wasn't* required to bond to the lighting cpc if you
only have SELV lights now? (Or am I going round in circles here...)

David

Lobster wrote:

But I thought it *wasn't* required to bond to the lighting cpc if you
only have SELV lights now?

By definition SELV (= *separated* extra low voltage) must be separated
from earth [etc.]. So you certainly mustn't bond to the ELV side (but
if you do it will no longer be SELV).

--
Andy

On Mon, 19 Feb 2007 23:21:03 GMT someone who may be Lobster
wrote this:-

But I thought it *wasn't* required to bond to the lighting cpc if you
only have SELV lights now? (Or am I going round in circles here...)

The strict interpretation is that it is not required if the
transformers are not within the zones. However, it is as well to do
it for the reasons already given and if it feeds any other equipment
in the zones it will have to be bonded anyway.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54