Guidance adding a spur to my lighting circuit

[RossOliver87]

Hello!

I've just finished flooring my loft and I've installed a double strip light currently just wired to a plug and into an extension I run to a wall socket when the hatch is open. Now I want to add a spur from one of my upstairs lights to the strip light so I don't need to run the extension. I've done wall socket spurs before but this is my first lighting spur...

As far as I can tell I have the circuit detailed at the top of this page (Method 1), as I see no junction boxes in my loft and each rose only appears to have one cable running to it (house was built 2008 and we're in Scotland, if that tends towards a certain circuit style?):

http://www.ultimatehandyman.co.uk/lighting_circuits.htm

Am I right in thinking I can simply take the feed directly from an existing ceiling rose to my new switch and then on to the strip light? (I'm confident on wiring the switch and strip light, I'm just not 100% sure if I'm safe to take the feed from an existing ceiling rose?). The light I'm planning on taking a feed from is a single light in a bedroom with only one switch attached...

Many thanks for your time,

-Ross

 

[EFLImpudence]

Am I right in thinking I can simply take the feed directly from an existing ceiling rose to my new switch and then on to the strip light?

Not if it is as in the diagram you say.

You will need to run a cable to a switch and then connect to permanent Live, Neutral & Earth - NOT the switched Live.

As -

each rose only appears to have one cable running to it

You will not be able to use a rose with only ONE cable to it as it will not have a permanent Live.

If you did the new light would only work when this light was ON.

 

[RossOliver87]

Ah, that all makes a lot of sense, thank you! Hopefully it will be easy enough to fish a wire from the loft down to a switch! I take it I just get the live feed from the COM on the switch?

Thanks again,

-Ross

 

[EFLImpudence]

Yes, plus the Neutral & Earth which will be there if wired as you say.

 

[Greenie9657]

I can't find my post now but someone came up with a great idea if you can do it. I was putting a light in my loft and was going to do the same until someone suggested spurring a loft light from the upstairs ring main. That way if you have any lighting problems upstairs you can isolate the circuit but still have the loft lite up for fault finding. Such a simple idea but genius.

If you can't then like someone has said. That's the switched live you'll have there which is no good for what you want.

 

[RossOliver87]

Yeah initially I wanted to stick a double socket up there but there's just no way to get a spur from a socket up to the loft easily...

I've taken a look at the switches I could take a feed from and there are three twin and earth wires to each switch, which will make cramming a fourth wire into the COM/earth/neutral terminals a little tight... what's the general thing to do in this case? Could I just chop one wire and stick another choc block in the switch box to take the feed from, or will the switch wire go up into the loft so I can chop it and put a terminal up there for the feed (I'll clamber up and check this, but is that generally how it's wired?)

Thanks!

-Ross

 

[EFLImpudence]

Could I just chop one wire and stick another choc block in the switch box to take the feed from,

Yes, that will be fine.

or will the switch wire go up into the loft so I can chop it and put a terminal up there for the feed

No, that's the point.
The switch wire is no good for what you want.
You have to connect to the wire (permanent live) which does not go up to the loft.

 

[RossOliver87]

Sorry, I used poor wording there - I meant a wire coming from the switch and going to the attic that has a permenant feed. I presume as there are three wires, one is the feed from the last switch, one goes from the switch to the light and one goes from the switch to the next switch in the circuit, so two out of the three will have a permanent live, is that right? Sorry, just trying to get a clear picture!

Many thanks,

-Ross