Adding an outside porch lamp

[doubledee]

Hi,
I currently have an inside porch lamp and single switch, and I want to add an outside lamp(PIR type). I would like to change the inside single switch to a double switch for isolation purposes for the outside one. The inner single switch has no neutral, and is hot live switched.
Any thoughts on how I can wire up the outside one and swap my single switch to a double. i.e will I have to go to the ceiling rose or should I just start a fresh spur with a junction box.

 

[EFLImpudence]

It depends on the access and cable routing.

You will need a cable from a supply somewhere - the light operated by the present switch would be better than a junction box, then
1. to the switch and then the light or
2. to the light and then the switch or
3. one cable to the light and another to the switch.

If 3. you can replace the existing switch cable with four core (3 core + earth)

 

[doubledee]

Many thanks,
I can get a feed from the existing light to the new light and a cable from the new light into the back of the switch patress box, so I think option 2 sound best for me.

 

[Taylortwocities]

and is hot live switched

Ooh, you don't hear that round here very often!