Electric cables and fuzse box right behind new shower - safe?

unwashed potato!

unwashed potato!

unwashed potato!

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We are having a new shower installed and the workers have run about 6 power cables right down the wall where tiles will go on top and then a shower space there. The shower mixer will be on the opposite wall, however I'm concerned that the power cables are in a vulnerable spot, completely inaccessible and potential for water, being drilled into etc. On the other side of the wall that the cables run on is our fuse box and main supply into the house.

I asked the workers if they are putting a metal sheet on top of the cables and I was told yes, but they are polish with little English, and today I come home to see one guy has just simple covered half the cables with a concrete mix, so no real protection but also is this an issue for over heating? The entire 6 cables are entirely encased in the concrete.

I will speak with the main guy again, but I want to get better advice before I do.

Is this safe/normal? The cables are recessed where they've dug out a small channel for them to run down.
 
So, you were right to ask about metal capping/protection. That's required as without a socket or switch on the wall, you wouldn't know from that side there's a cable there. They should be installing mechanical protection.

AFAIK that's all that's needed here, yes it's fine to run cables somewhere they'll be hard to access later even behind tiles... That's true of most hidden cables. But the safe zone/mechanical protection has a clear policy.
 
Hey,

Metal capping does not provide mechanical protection. If the cables are less than 50mm from the surface and not within a permitted zone they require mechanical protection, such as conduit.

This is a breach of regulation 522.6.201 (if I remember right)
 
4Qman said:
Hey,

Metal capping does not provide mechanical protection. If the cables are less than 50mm from the surface and not within a permitted zone they require mechanical protection, such as conduit.

This is a breach of regulation 522.6.201 (if I remember right)
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Thanks. I've searched that regulation and that seems to relate to ceiling and floors rarher than walls?
 
Image of it helps. The 2 sockets have gone. Originally the grey cables came out the ceiling and want right out of view, came down the wall behind a then fridge, then ran back to the hole they go into on the floor. The electrician moved them to go straight down the wall, but this is exactly where the mixer was going to go, so that mixer and pipes will now go opposite wall. My biggest concern is just not expecting cables to be there,ahne drill into the eventual tiles to put a shelf etc and hit the power cables, in a room with water, and the other side of the wall is the fuse box, so less ideal to have water run to that!

PXL-20221018-123520341.jpg
 
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Sin_Chase said:
Errr...not even in conduit?

Are those cables going to be buried in whatever the wall finish is!?

Looks like a lazy bodge
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I asked about some sort of protection and was told yes, but I come home today and fine the top half of what you see in the image just covered in concrete.

Assume they will cover the rest in concrete mix and then tiles on top and done.
 
I would not be happy at cable being concreted into the wall like that and not in conduit first and would stop their work ASAP.


 
unwashed potato! said:
My biggest concern is just not expecting cables to be there,ahne drill into the eventual tiles to put a shelf etc and hit the power cables, in a room with water, and the other side of the wall is the fuse box, so less ideal to have water run to that!
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You should always expect cables to be there and test before drilling of course. It's hard to tell how deep those cables are in the wall but it doesn't look like good work too me.

Sin_Chase said:
Ignoring everything else...I think having 6 cables I can no longer maintain would bother me.
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How do you maintain 99% of cables in your home then?
 
rcd requirement ?
professional-electrician.com

Cables Concealed in Walls or Partitions: The Case for Additional Protection by Residual Current Devices

BS 7671: 2008 (2015) Requirements for Electrical Installations contains recommendations that a cable installed in a wall or partition must, in many cases, be provided with additional protection by mea
professional-electrician.com professional-electrician.com
As detailed in the Notes to Figures 1 and 2, there is no requirement to provide additional protection by an RCD if the cable concealed in the wall or partition has an earthed metal covering (such as armour), or is contained in earthed metal conduit or trunking, provided that the metal covering, conduit or trunking meets the requirements of BS 7671 for a protective conductor of the circuit. Additional protection by an RCD is also not required if certain requirements for mechanical protection are met, as stated in the notes to Figures 1 and 2, or if the cable forms part of a SELV or PELV circuit meeting the requirements of Regulation 414.4.

=> 4 cables derated 65%

Table 4C1 Rating factors for one circuit or one multicore cable or for a group of circuits, or a group of multicore cables, to be used with current-carrying capacities of Tables 4D1A to 4J4A
Arrangement (cables touching) Number of circuits or multicore cables To be used with current-carrying capacities, reference 1 2 3 4 5 6 7 8 9 12 16 20 Bunched in air, on a surface, embedded or enclosed 1.00 0.80 0.70 0.65 0.60 0.57 0.54 0.52 0.50 0.45 0.41 0.38 Methods A to F
Single layer on wall or floor 1.00 0.85 0.79 0.75 0.73 0.72 0.72 0.71 0.70 0.70 0.70 0.70 Method C
 
Sorry if I am making no sense, I didn't read all the posts.

LuckyBenski said:
So, you were right to ask about metal capping/protection. That's required as without a socket or switch on the wall, you wouldn't know from that side there's a cable there. They should be installing mechanical protection.

AFAIK that's all that's needed here, yes it's fine to run cables somewhere they'll be hard to access later even behind tiles... That's true of most hidden cables. But the safe zone/mechanical protection has a clear policy.
Click to expand...

No, it's not required, as long as you have a modern fuse box fitted with an 30ma rcd.
It really is not a wise place to run cables. Although I am unaware of any regulations that they are actually breaking their location is definitely against "recommendations". They do not look like they are very deep and they are certainly too far from the corner of the room. The least I would do is bury them deeper, but that's just me.
 
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As I see them they are not compliant, they are not in a permitted zone and do not have mechanical protection.

Speak to the electrical company carrying out the work.
 
They are not in a zone, they dont have mechanical protection. That's the regs...

They are/should be signing the installation certificate on completion that states that they have installed in accordance of bs7671.
 
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