Probably dumb lighting question.

I am about to add some lighting to my loft, picking up the power from a ceiling rose. The power in to the ceiling rose will be diverted to a junction box, and replaced by a power in from the junction box.
O.K. - now I have a junction box with power. My DIY book shows the usual way of wiring a switched light.
Live -> Switch (red) Live <- Switch (neutral wire marked to show live) Switched live -> Light fitting (red) Neutral <- light fitting (black)
Posts passim have emphasised that you should always switch live not neutral. However the spur off the existing power will be a long one before I reach the switch. So I have two options.
(1) Take the power spur to the switch, and just treat this as an inline switch with the neutral/live return in a choc block (assume the back box is deep enough).
(2) Put in another junction box near the switch.
Any reason not to do (1)? Saves on a junction box.
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On Mon, 09 Apr 2012 13:24:42 +0100, David WE Roberts wrote:

I'd do (1) but use a double pole switch. No choc block necessary.
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On 9 Apr 2012 12:41:06 GMT, Bob Eager wrote:

+1
But I'd carefully open the cable and only cut the live to insert the single pole switch. Earth also cut and sleeved, rejoined in the back box's earth terminal.
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David WE Roberts wrote:

Can I ask a dumb question as I do not 100% understand your plan:-(?
Is the permanent line, neural and earth from the junction box close to where where the loft lightswitch will be?
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Not at the moment. I plan to pick up the permanent LNE at the other end of the loft, using a junction box. I then plan to run a spur from this junction box from one end of the loft to the other end of the loft by the loft hatch. At this point I need to add a switch, before I go on to the light fitttings.
So the question is, do I spur the permanent LNE to a junction box near the loft hatch, then proceed as usual with a junction box system, or can I dispense with the junction box by the loft hatch and instead just use a choc bloc in the switch back box to complete the circuit? i.e. permanent LNE -> switch + choc bloc -> light fitting(s)
Bob suggested using a double pole switch but I don't seem to have one in stock at the moment - although I was a bit shocked at how much stock I have once I started rooting through all the boxes.
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David WE Roberts wrote:

I get you:-)
You are after http://wiki.diyfaq.org.uk/index.php?title=House_Wiring_for_Beginners#Other_Wiring_Options the right hand picture but without the cable to the next light fitting.

A switched fused spur would do the same job as a double pole switch:-)
But the chock block if fine.
I hope I got it right this time:-)
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Theres no reason at all to add a 2nd jbox. Just run L,N,E to the switch, and from there swL,N,E to the light fitting.
If you can get another cable into the lighting rose, then there'd be no need for the first jbox either.
NT
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Theres no reason at all to add a 2nd jbox. Just run L,N,E to the switch, and from there swL,N,E to the light fitting.
If you can get another cable into the lighting rose, then there'd be no need for the first jbox either.
***************************************************
I need to spend more time trawling through the Wiki!
Three cables into a ceiling rose is my limit - I am never good at fitting a quart into a pint pot.
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