Bathroom refit, do I need a RCD?

[timhoward]

Hi again Tim, when I get it tested, how does the tester assess the supplementary bonding? If it is by inspection should I remove the bath panel so that they can see the pipes?

No, I wouldn't remove the panel (oh that all home owners would think in such an obliging way!)

A lot of installations would meet the 3 requirements in section 701 (automatic disconnection of supply for all circuits in room, RCD protection for all circuits in room, and all extraneous conductive parts are bonded) which would mean supplementary bonding isn't required.
You don't have RCD protection for all circuits in room, so be default supplementary bonding is required.
So next question is are there any metallic parts that could introduce a potential in the bathroom (extraneous conductive parts).
If there are then the CPC of all circuits in the room need to be connected to the extraneous conductive parts with supplementary bonding.

From what you've said it sounds as though the copper pipe to the toilet cistern might be a contender.
You haven't mentioned any heating in there - is the a radiator / towel rail with metal pipes?

Having determined that supp. bonding is required, and there are items that require it, it's usually quickest to use continuity tests to check the resistance between the items is low enough to keep the touch voltage below 50v. There's a formula in the regs for how low it needs to be.

 

[Johnstar]

No, I wouldn't remove the panel (oh that all home owners would think in such an obliging way!)

A lot of installations would meet the 3 requirements in section 701 (automatic disconnection of supply for all circuits in room, RCD protection for all circuits in room, and all extraneous conductive parts are bonded) which would mean supplementary bonding isn't required.
You don't have RCD protection for all circuits in room, so be default supplementary bonding is required.
So next question is are there any metallic parts that could introduce a potential in the bathroom (extraneous conductive parts).
If there are then the CPC of all circuits in the room need to be connected to the extraneous conductive parts with supplementary bonding.

From what you've said it sounds as though the copper pipe to the toilet cistern might be a contender.
You haven't mentioned any heating in there - is the a radiator / towel rail with metal pipes?

Having determined that supp. bonding is required, and there are items that require it, it's usually quickest to use continuity tests to check the resistance between the items is low enough to keep the touch voltage below 50v. There's a formula in the regs for how low it needs to be.

Lovely reply Tim,
So yes the pipe to the toilet cistern is copper and extraneous, it is bonded with a strap and earth cable running back to the CU main earth block. The other parts that introduce potential are the fan isolation switch and the shaver socket both with metal back boxes connected to the protective conductor. The one central light also has a metal case and I will replace this with a modern plastic one. All of these are in the Outside Zone. The light switch is outside the room.
There is no heating in the room and no other metal parts entering from outside.
With the resistance test, if they were to check the taps, they would be open circuit due to the plastic pipes, how would they know the difference between a failed bonding test and plastic pipe?

 

[swaRRR]

Yes. Domestic installs now all circuits require RCD protection if i remember rightly. Would have to check regs to be 100% but as far as i remember you're only allowed to not have RCD protection in commercial premises and only when the appropriate risk assessments have been done to justify not having it.

 

[Johnstar]

Yes. Domestic installs now all circuits require RCD protection if i remember rightly. Would have to check regs to be 100% but as far as i remember you're only allowed to not have RCD protection in commercial premises and only when the appropriate risk assessments have been done to justify not having it.

Hi,
Thanks this was also pointed out by Westwood so I have decided to leave the electrics alone and just change the light fitting to a modern one. I did fancy downlights but it’s going to be too expensive if I have to fit an RCD.

So now the question is, can I pass a EICR as it stands with the original consumer units and no RCD?

 

[timhoward]

So yes the pipe to the toilet cistern is copper and extraneous, it is bonded with a strap and earth cable running back to the CU main earth block.

Good stuff, though are you 100% sure that is where it goes? (The fact there is bonding in this location at all suggests someone has already considered this topic and it is supplementary bonding that links up to other accessories in the room.)
The idea is that you can't touch a faulting accessory (e.g. shaver socket) and path to earth without both things being held at the same potential via a direct link of low resistance.

With the resistance test, if they were to check the taps, they would be open circuit due to the plastic pipes, how would they know the difference between a failed bonding test and plastic pipe?

Well to be extraneous it has to leave the room, so first you try and test to somewhere handy just outside e.g an airing cupboard or sometimes a combi boiler. If it's testing open circuit it's reasonable to assume they are plastic pipes or there's an insulated joint in the middle.
If it's low-ish, then you test from the tap to a cpc in the room, and you then find out whether you are looking at the resistance of a fairly short length of bonding cable, OR a larger resistance representing the total path along the pipe, via the main bonding, to the MET, back to the consumer unit and along the CPC of the circuit.
You need an accurate continuity tester (or multi function tester) to do this, multimeters are usually not accurate enough.

We have gone down a slight rabbit hole here - it's a much better use of effort to get the CU upgraded so the complexities of this topic can be brushed aside!

So now the question is, can I pass a EICR as it stands with the original consumer units and no RCD?

I'm not trying to be pedantic, but EICR's aren't pass or fail, you get a report with C1 (dangerous), C2 (potentially dangerous), C3 (improvement recommended).
If rented out C1's and C2's are supposed to be rectified within a fixed time frame (which I forget tonight - 2 weeks?).
If privately owned, you ignore C2's and above at your own peril!

Yes, it is possible to only have C3's in your situation.
It's still a flipping good idea to have RCD protection though!

 

[westward10]

Yes. Domestic installs now all circuits require RCD protection if i remember rightly. Would have to check regs to be 100% but as far as i remember you're only allowed to not have RCD protection in commercial premises and only when the appropriate risk assessments have been done to justify not having it.

This is not correct.

 

[Johnstar]

Good stuff, though are you 100% sure that is where it goes? (The fact there is bonding in this location at all suggests someone has already considered this topic and it is supplementary bonding that links up to other accessories in the room.)
The idea is that you can't touch a faulting accessory (e.g. shaver socket) and path to earth without both things being held at the same potential via a direct link of low resistance.

Well to be extraneous it has to leave the room, so first you try and test to somewhere handy just outside e.g an airing cupboard or sometimes a combi boiler. If it's testing open circuit it's reasonable to assume they are plastic pipes or there's an insulated joint in the middle.
If it's low-ish, then you test from the tap to a cpc in the room, and you then find out whether you are looking at the resistance of a fairly short length of bonding cable, OR a larger resistance representing the total path along the pipe, via the main bonding, to the MET, back to the consumer unit and along the CPC of the circuit.
You need an accurate continuity tester (or multi function tester) to do this, multimeters are usually not accurate enough.

We have gone down a slight rabbit hole here - it's a much better use of effort to get the CU upgraded so the complexities of this topic can be brushed aside!

I'm not trying to be pedantic, but EICR's aren't pass or fail, you get a report with C1 (dangerous), C2 (potentially dangerous), C3 (improvement recommended).
If rented out C1's and C2's are supposed to be rectified within a fixed time frame (which I forget tonight - 2 weeks?).
If privately owned, you ignore C2's and above at your own peril!

Yes, it is possible to only have C3's in your situation.
It's still a flipping good idea to have RCD protection though!

Thanks once again for a great reply.
First point is yes, I’m absolutely sure because I stripped out (cut off) the old copper pipes as they were 15 mm copper sunk into the concrete floor with no insulation or protection of any kind. As I was replacing the old fortic cylinder with a mains pressure one I didn’t trust the old pipes. I’ve run the new pipes from the new cylinder in plastic up and through the loft. Plastic for lower heat loss and ease of run. The old pipes were bonded and connected to the earth block via a thick cable that runs up to the loft and down to the earth block next the CUs.

It’s very difficult to see how you could get a shock in this room as there is simply very little in there and very little exposed at earth potential, the very short pipe to the cistern, and the 4 screw heads for the fan switch and shaver socket.

I agree completely that an RCD would be best and safer but changing the two consumer units is an expense I can’t afford at the moment with everything else going on. Should I rent it in the future I will however change the CUs.

Thanks for the information about the EICR and testing I didn’t know that about the fault classifications.
I remember using a Mega when testing for earth continuity on industrial equipment, it used a much higher current than a standard multimeter and could measure very low resistances. I guess there is an equivalent that you guys use for this work.

Thank you very much Tim this has made things much clearer for me.
Cheers

 

[davesparks]

Yes. Domestic installs now all circuits require RCD protection if i remember rightly. Would have to check regs to be 100% but as far as i remember you're only allowed to not have RCD protection in commercial premises and only when the appropriate risk assessments have been done to justify not having it.

Utter nonsense!

 

[HappyHippyDad]

No they are SB6000. They did make rcbos for them but were two module and would now be second hand. Finding one for a 6 or 10A lighting circuit is likely to be difficult. It is likely they never existed.

I remember looking for a 6A one a few years back. I found a few 32A and 16A but never any other rated ones.

 

[davesparks]

I remember looking for a 6A one a few years back. I found a few 32A and 16A but never any other rated ones.

That's not surprising, in those days the use of RCBO's was much like the current situation with AFDDs. Most people didn't see the need for them, some people did fit them but only when absolutely necessary and that would almost exclusively be socket circuits hence 32A being the most commonly available 2nd hand.

 

[swaRRR]

Utter nonsense!

Lol you've glossed over where i said i wasn't sure?

You know it would add to the conversation if you actually said what the rule was instead of just saying 'nonsense'.

 

[Johnstar]

Lol you've glossed over where i said i wasn't sure?

You know it would add to the conversation if you actually said what the rule was instead of just saying 'nonsense'.

Just for giggles mate, you said that you weren’t 100% sure which mean that you were somewhere between 0% and 99% sure. It would be useful if you could narrow down the range of sureness a bit!
No offence mate just giggling

 

[Johnstar]

Yes. Domestic installs now all circuits require RCD protection if i remember rightly. Would have to check regs to be 100% but as far as i remember you're only allowed to not have RCD protection in commercial premises and only when the appropriate risk assessments have been done to justify not having it.

Hi,
Found this in a video of 18th addiction changes.
It’s not the full regulation, just an overview of what has changed since 17th but it does mention the risk assessment.
The vid is by John Ward

 

[timhoward]

Hi,
Found this in a video of 18th addiction changes.
It’s not the full regulation, just an overview of what has changed since 17th but it does mention the risk assessment.
The vid is by John Ward

JW makes good videos, but due to the whirlwind world we live in it is sadly already out of date as amendment 2 to the 18th edition (mandatory from end of current month) has further changes.

From a domestic point of view you mainly need to know that the latest regs require socket circuits and lighting circuits to have 30ma Type A RCD protection. New work needs to meet this standard.

While a risk assessment and omitting RCD protection is possible, the permitted circumstances are so narrow in amendment 2 that it isn't worth describing it in detail. It will never apply to domestic installations as there will always be unskilled / ordinary people present.

 

[Johnstar]

JW makes good videos, but due to the whirlwind world we live in it is sadly already out of date as amendment 2 to the 18th edition (mandatory from end of current month) has further changes.

From a domestic point of view you mainly need to know that the latest regs require socket circuits and lighting circuits to have 30ma Type A RCD protection. New work needs to meet this standard.

While a risk assessment and omitting RCD protection is possible, the permitted circumstances are so narrow in amendment 2 that it isn't worth describing it in detail. It will never apply to domestic installations as there will always be unskilled / ordinary people present.

To summarise my situation:
If I change the existing light for another it is NOT a new installation.
If I replace the light with say 4 downlights then it IS a new instillation.
All new instillations have to meet the current regs which means an RCD would be mandatory.
There is no requirement to fit an RCD as long as the unchanged current installation complies with the regulations at the time it was designed (1989) with bonding.

It is always desirable and safer to fit an RCD and I will do this when I have the money and at that point I may fit the downlights.

 

[UNG]

Lol you've glossed over where i said i wasn't sure?

You know it would add to the conversation if you actually said what the rule was instead of just saying 'nonsense'.

Why engage the keyboard if you are not sure if your wrong you are most certainly going to be shot down

 

[UNG]

Yes, understood. I have been told I need an EICR by the management company. I’m starting to think that they have this wrong as I’m the owner and it’s not going to be rented in the near future anyway.

It is quite common for management companies who are managing blocks of flats to require an EICR every 5 years for all the individual flats regardless of whether they are owner occupied or rented out to ensure all parts of the property is a safe condition

As it’s just me, I’m happy without any RCDs especially due to the cost ( I’m guessing hundreds of £s) but I’m worried that when I get it inspected it will fail. Now I’m questioning if I need to get it inspected at all?

The problem you may have is the condition of the electrical installations in the other flats if they all have RCD's it may look odd that you haven't and the management company may request that you fit them. The part of the EICR that may draw attention to the lack of RCD's is the observations as codings will highlight the parts of the installation that needs improvement or remedial work

 

[Johnstar]

It is quite common for management companies who are managing blocks of flats to require an EICR every 5 years for all the individual flats regardless of whether they are owner occupied or rented out to ensure all parts of the property is a safe condition

The problem you may have is the condition of the electrical installations in the other flats if they all have RCD's it may look odd that you haven't and the management company may request that you fit them. The part of the EICR that may draw attention to the lack of RCD's is the observations as codings will highlight the parts of the installation that needs improvement or remedial work

Hi UNG,
Thanks for the reply, a bit more for me to consider.
On a further note, I have two CUs in the flat one that is energised twice a day for storage heat and hot water and the other for lights and sockets etc.

Given the storage heat one does not have any sockets attached as the heaters all have switched fixed outlets, does that also come under the RCD regulations?

I keep reading RCDs are required for lights and sockets, no one mentions fixed outlets.

 

[brianmoooore]

Any cable buried in a wall at a depth of between 0 mm and 50mm needs 30mA max. RCD protection .

 

[Johnstar]

Any cable buried in a wall at a depth of between 0 mm and 50mm needs 30mA max. RCD protection .

Thanks Brian,
That makes sense, just in case someone bangs a nail in ️