I want to replace an existing wall light in a bathroom with a lighted mirror, but the wire is too short! Is it possible to extend the wire safely, if so how, or do I need to replace the whole length by tracing it back to its connection in a ceiling rose ? I want to avoid replacing the whole length if possible!
Thanks

 

You cannot extend the wire unless you can somehow install a permanently accessible junction box. It sounds like your only option is to replace the wire back to it's source.

 

A splice would have to be, as mentioned above, permanently accessible - meaning a junction box with a cover plate. Depending on your application (how the mirror fits on the wall), you might be able to do what you want, though it would mean adding another junction box at the point the mirror ties into the electrical system.

 

Is it OK to install a junction box in the loft, cut the existing wire & connect to the junction box. Then run a new wire of the correct length to the mirror? I presume I need a 20A standard junction box & connect Red to Red , Black to Black & Earth to Earth ?
Thanks

 

Your terminology indicates you may not be from the US. You should state your location in your profile, or at least in your post, so that you can get accurate answers.

In the US, a junction box in the attic or loft would be considered permanently accessible.

 

Sorry, yes I am based in the UK.