Dear all
This may be a bit of a long post and I have looked through the forum for relevant posts in the past, but, to be blunt, this supplementary bonding thing seems to be a bit of a minefield and it’s hard to pick out the information I need from the posts. So apologies in advance for the length of my post and if my questions have been answered elsewhere.
A little background.
We’ve rented a house while we look for another plot of land to build a new house. The electrician we used for our previous build went to great lengths to install, what I now know to be, supplementary bonding in our bathrooms. I thought he was going a bit over the top with the bonding but after spending a couple of days reading posts on this forum, I can see why he needed to bond the bathroom and en-suite (due to current regulations regarding safety in Special Locations).
I’ve noticed in the house that we’re renting there seems to be no supplementary bonding at all (other than the kitchen). There is a main bathroom, an en suite, a downstairs loo, a kitchen and a utility room.
The main bathroom has a bath, basin, WC and radiator. There is also a shaver socket, ceiling light, pull cord switch and a down light in a cabinet (a kitchen type cabinet) that is directly above the basin. The cabinet and light are approximately 850mm above the basin and the light is connected to a 1.5mm cable that disappears into the wall behind the cabinet. This down light is live, but I can’t see a transformer so I guess it’s fed with 240 volts. None of the pipe work (it’s all copper) that is visible has any bonding to it.
The en suite has a shower (not electric), basin, WC and radiator. Again there is a shaver socket, ceiling light, pull cord switch and a live down light in a cabinet 850mm above the basin (similar to the cabinet in the main bathroom). The wiring of this down light is the same as the main bathroom. And all the visible pipe work (copper) lacks any bonding.
The utility room and down stairs WC lack bonding too, but I’ve read in other posts that it is not required in these rooms as there is no bath or shower. The kitchen does have bonding connected to the copper hot and cold taps, but I’m guessing that this bonding is part of the Main Bonding as the earth cable (4mm I think) disappears into the wall and I assume goes back to the consumer unit. There is no MET by the consumer unit or in the outside cupboard where the meter is installed, so I’m guessing all the earth cables are connected together inside the Consumer Unit.
OK to my questions, in no particular order …
Question 1
The house appears to have been built in 2001 (there is a sticker on the Consumer Unit stating it was installed then). As the Part P regulations came out in 2005, should this house have supplementary bonding in the bathroom and en suite or is it exempt ?
Question 2
The down lights above the basins in the bathroom and en suite worry me, especially since my wife is pregnant. They are of the type that you would see in a kitchen ceiling, ie not sealed either around the bulb (this is held in by a metal ring) or inside the cabinet (it’s possible to open the cabinet and touch the part of the down light that would ordinarily be hidden in the ceiling). Can these down lights be that close to a basin and unprotected ?
If not, how can they be made safe ?
Question 3
Supplementary bonding is not designed to make a circuit trip out in the event of a fault, it’s designed to bring any exposed metal like pipe etc work to a similar voltage. For example. Without bonding, if for some reason the cold tap to the basin was to become live, touching the hot tap (that wasn’t live) would result in an electric shock. But with bonding, both taps would become live (should the same fault mentioned above occur), but because the hot and cold taps are connected by the bonding, there would be no difference in voltage between the two taps and no one would get a shock. Do I understand how supplementary bonding works correctly ?
Also, if, say the hot tap was to become live, why wouldn’t the circuit trip out at the consumer unit ? Surely that’s what the MCB’s are designed to do.
Question 4
If supplementary bonding is required to be added to the bathroom and en suite. All that is required is a single earth cable (4mm or bigger) to be connect to all the pipe work and then be connected to the earth cable of the light fitting or shaver socket ?
Question 5
SELV – what is this ? I’ve read in various places that electrical fittings can be placed in Special Locations without additional bonding if they are SELV. Could the down lights in the cabinets above the basins be SELV devices and how could I check ?
Question 6
Assuming that supplementary bonding is required, that it hasn’t been installed, that the electrician who has inspected the electrics hasn’t checked the bonding exists and that no accidents regarding an electric shock occur. What’s the big deal ?
I’m not trying to be awkward, but who would care about the lack of bonding in my bathrooms, the Health and Safety Executive, NICEIC ?
I would be grateful for any comments from the members of the forum that would help me sort out and understand a bit more about bonding in special locations. Thanks for taking the time to read through this post.
John.
This may be a bit of a long post and I have looked through the forum for relevant posts in the past, but, to be blunt, this supplementary bonding thing seems to be a bit of a minefield and it’s hard to pick out the information I need from the posts. So apologies in advance for the length of my post and if my questions have been answered elsewhere.
A little background.
We’ve rented a house while we look for another plot of land to build a new house. The electrician we used for our previous build went to great lengths to install, what I now know to be, supplementary bonding in our bathrooms. I thought he was going a bit over the top with the bonding but after spending a couple of days reading posts on this forum, I can see why he needed to bond the bathroom and en-suite (due to current regulations regarding safety in Special Locations).
I’ve noticed in the house that we’re renting there seems to be no supplementary bonding at all (other than the kitchen). There is a main bathroom, an en suite, a downstairs loo, a kitchen and a utility room.
The main bathroom has a bath, basin, WC and radiator. There is also a shaver socket, ceiling light, pull cord switch and a down light in a cabinet (a kitchen type cabinet) that is directly above the basin. The cabinet and light are approximately 850mm above the basin and the light is connected to a 1.5mm cable that disappears into the wall behind the cabinet. This down light is live, but I can’t see a transformer so I guess it’s fed with 240 volts. None of the pipe work (it’s all copper) that is visible has any bonding to it.
The en suite has a shower (not electric), basin, WC and radiator. Again there is a shaver socket, ceiling light, pull cord switch and a live down light in a cabinet 850mm above the basin (similar to the cabinet in the main bathroom). The wiring of this down light is the same as the main bathroom. And all the visible pipe work (copper) lacks any bonding.
The utility room and down stairs WC lack bonding too, but I’ve read in other posts that it is not required in these rooms as there is no bath or shower. The kitchen does have bonding connected to the copper hot and cold taps, but I’m guessing that this bonding is part of the Main Bonding as the earth cable (4mm I think) disappears into the wall and I assume goes back to the consumer unit. There is no MET by the consumer unit or in the outside cupboard where the meter is installed, so I’m guessing all the earth cables are connected together inside the Consumer Unit.
OK to my questions, in no particular order …
Question 1
The house appears to have been built in 2001 (there is a sticker on the Consumer Unit stating it was installed then). As the Part P regulations came out in 2005, should this house have supplementary bonding in the bathroom and en suite or is it exempt ?
Question 2
The down lights above the basins in the bathroom and en suite worry me, especially since my wife is pregnant. They are of the type that you would see in a kitchen ceiling, ie not sealed either around the bulb (this is held in by a metal ring) or inside the cabinet (it’s possible to open the cabinet and touch the part of the down light that would ordinarily be hidden in the ceiling). Can these down lights be that close to a basin and unprotected ?
If not, how can they be made safe ?
Question 3
Supplementary bonding is not designed to make a circuit trip out in the event of a fault, it’s designed to bring any exposed metal like pipe etc work to a similar voltage. For example. Without bonding, if for some reason the cold tap to the basin was to become live, touching the hot tap (that wasn’t live) would result in an electric shock. But with bonding, both taps would become live (should the same fault mentioned above occur), but because the hot and cold taps are connected by the bonding, there would be no difference in voltage between the two taps and no one would get a shock. Do I understand how supplementary bonding works correctly ?
Also, if, say the hot tap was to become live, why wouldn’t the circuit trip out at the consumer unit ? Surely that’s what the MCB’s are designed to do.
Question 4
If supplementary bonding is required to be added to the bathroom and en suite. All that is required is a single earth cable (4mm or bigger) to be connect to all the pipe work and then be connected to the earth cable of the light fitting or shaver socket ?
Question 5
SELV – what is this ? I’ve read in various places that electrical fittings can be placed in Special Locations without additional bonding if they are SELV. Could the down lights in the cabinets above the basins be SELV devices and how could I check ?
Question 6
Assuming that supplementary bonding is required, that it hasn’t been installed, that the electrician who has inspected the electrics hasn’t checked the bonding exists and that no accidents regarding an electric shock occur. What’s the big deal ?
I’m not trying to be awkward, but who would care about the lack of bonding in my bathrooms, the Health and Safety Executive, NICEIC ?
I would be grateful for any comments from the members of the forum that would help me sort out and understand a bit more about bonding in special locations. Thanks for taking the time to read through this post.
John.