I am encountering difficulty in replacing one FT lighting wire,
no CPC. It has been run in concrete, with hessian embedded,
on crap-block-coke wall, with chicken wire overlay & plaster.

Removal may damage flock lined wallpaper on the other side.
It is the sole 2-core cable drop to a switch, although I notice
another switch & light the other side which begs the question
of how that receives a supply or return with no other cable.


The alternative is 4mm^2 6491X to the architrave backbox,
right back to the CU (or a locally FTE rewired lighting circuit).
No class-1 lighting device, metal backbox needs an earth.

Is this still regarded as good practice?

I notice the following document suggests doing the same...
http://www.elecsa.org.uk/downloads/p...nnecting%20Lig
hting%20Circuits%20with%20no%20Protective%20Conduc tor.pdf

Link will need manual rejoining to BS7671 :-)

Interesting PDF used by NICEIC ECA etc.

Thanks.
--
JSB.