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[beegee]

I'm building a bedroom with en-suite in the loft. I've already extended the existing upstairs ring main power circuit into the loft. Can i connect a 1 way Consumer Unit to this ring main and use it to power the lighting circuit?
A separate question - must I use twin brown and earth core cables from the juntion boxes to all of the light switches to identify that they are switched live cables?
Thanks for any help you can provide

[ericmark]

One would normally use a fused spur to power lights from a ring main but you can’t do this for the only lights in a room 314.1 Every installation shall be divided into circuits, as necessary, to: (iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit.
As to cable colours it is permissible to sleeve cables which is normal and you can buy hanks of brown sleeving for this job or even use insulation tape.
Remember we are now on the 17th Edition which makes it plain the division of circuits rule also includes RCD’s and any cables not complying with BS 5467, BS 6346. BS 6724, BS 7846, BS EN 60702-1 or BS 8436 and buried less than 50mm in a wall or floor need RCD protection and bathrooms and sockets under 20A also need RCD protection so since you have en-suite I would think all circuits need RCD protection. Also because of the en-suite it will come under Part P. I would look at using GuardianTM, EarthshieldTM, FlexishieldTM, or AfumexTM cables I am told now the price is coming down and not that much different to old twin and earth and is rated 90 deg and does not need protection in a stud wall.
Eric