Help With Lighting cable

[wisemang]

Hi All

Can anyone please please help. I have a mirror on the wall in the bathroom with lights within that is operated from a standard switch outside the bathroom.I am about to re-tile the bathroom and intend to move the mirror about 3 feet to the right .Therefore i want to extend the 2 cables ( one form switch and one form rose) Without the need of of replacing all as i cannot get to replace it all due to loft being boarded and bedroomed.Is there a way i can maybe extend these cables and just drop a connector into the cavity wall ?

Wires are cable 1 Red.black.earth cable 2 2 red i earth

Please help with suggestions

 

[ban-all-sheds]

Drawing/photos would be useful, but my immediate reaction is no:

1) You may end up with problems regarding where concealed cables run:

• http://www.voltimum.co.uk/files/gb/attachments/niu/l/attachments/c5-43.pdf
  
  
• http://web.archive.org/web/20061110111450/http://www.niceic.org.uk/downloads/concealedcables.pdf
  
  
• IEE article
  
  
• Current Wiring Regulations requirements for concealed cables.

2) Junction boxes need to be accessible

3) Cables in cavity walls are not recommended - Guidance from the Electricity Safety Council says "installing such cables in this way (external cavity walls) is generally an undesirable practice"

The reasons give are
a. Obstructions in a cavity wall, such create a risk of unseen damage during installation.
b. Long unsupported vertical drops may place undue strain on the conductors, leading to damage
c. Polystyrene used for insulation, if it come into contact with thermoplastic (pvc) cable sheathing, plasticiser can migrate from the thermoplastic to the polystyrene
d. Thermal insulation in the cavity may cause cable not to be able to carry the load current without overheating due to their current-carrying capacity being reduced
e. Presence of flora and fauna - unforeseen external influences


Also, not that this is a reason why you can't do it, but bear in mind that the work is notifiable.

 

[wisemang]

Cheers for that

To be fair its not a external cavity wall.It is a studded Plaster board wall.Which i pre-sume cables run down all the time for switches etc. I did try to put a Block connector on it but when i switched the light fuse back on it tripped out .......Why would it do this ?

 

[Alarm]

Cables in the wrong place?

 

[ban-all-sheds]

To be fair its not a external cavity wall.It is a studded Plaster board wall.Which i pre-sume cables run down all the time for switches etc.

OK, so only (1) and (2) to worry about.

I did try to put a Block connector on it but when i switched the light fuse back on it tripped out .......Why would it do this ?

As Alarm said - you must have connected the wrong conductors together. Did you join any together that were not joined at the light?

 

[pepelectric]

You can safety use butt connectors but You need crimping tool to do that. You have to make that very properly and please check after quality of the connections. After that all wire wrap insulation tape (that will give You double insulation). That connection when is done properly is safe

Removed

 

[Taylortwocities]

After that all wire wrap insulation tape

No you do not.

Use heat shrink sleeving, or self-amalgamating tape.

Insulation tape can only be regarded as a temporary device. Most modern-day plastic tapes will come unstuck over time and there goes your insulation.

 

[ban-all-sheds]

Please call it sticky tape - it does not meet any of the requirements for an insulation material.

 

[Taylortwocities]

Wilko cap'n

EDIT

Or perhaps

"sticky for a while tape"
or " sticky until it gets cold tape"
or "sticky until it gets hot tape"
or " not really sticky at all tape"

 

[ban-all-sheds]

Good man.

Carry on, TTC.

 

[securespark]

Wilko cap'n

You can buy it from there if you must...