2nd floor lighting

[Matthew Ames]

As I am in the process of putting in ceiling insulation into my 2nd floor bedrooms and landing, I thought I might as well re-route my lighting cables. The house is an old Victorian place which up till now had old style (red/black with a white outer) nailed to the walls and then wallpapered over (classy!). As I am pulling up new ceilings and generally making a mess I might as well channel the cables into the wall.

Now here comes my question, do I reuse the existing cable which looks to be in good condition, or should I replace with modern harmonised wire? The only issue I can see with replacing the wire, is that feed from the fuse box is already plastered into the walls on the floor below before it reaches to the fuse boxes by the front door. (and I have no desire to pull it out of the wall).

Is it acceptable to use a junction box to join the two types of cable together, or shall I just reuse the old wire?

Thanks, Matt

[Dave Plowman (News)]

If the old is in good condition and has the correct earth conductor and that is connected, it's fine to just channel it into the wall, observing the rules for this. You can joint to the new cable colours, but a note should be visible at the CU saying both are in use.

[Matthew Ames]

Excellent. I'll check that I have enough cabling for my new proposed route, and if the old stuff appears as good as it did for a quick glance then I shall recycle it :-)

Thanks.

[Tim Watts]

I would put in new cables where you are working for the minute cost - then you know you have 40 years or more of potential service from them. Even better, if you can figure out how to run some 20mm conduit, with gentle bends into the ceiling right to the light and back down to the floor, then you have a way to replace them if needs be without wholesale destruction.

Cable is fairly cheap and conduit is very cheap - so if you can, I would always advise doing it belt and braces.

No matter what the old cables look like, if you do end up burying cables in plaster, I see no point in burying old stuff.

You can junction them. Basic rules are:

Accessible (ie unscrew floorboard) then screw terminals junction box is OK.

Inaccessible (or likely to be so) then either maintenance free sprung terminals (there is debate on how well these fair, but if the manufacturers rate them as such then there isn't a lot else to go on...) or, best, a crimp joint in a little box, done with a proper ratchet crimper, not the Halfords pliers crap.

And, as mentioned by Dave IIRC, a sign on the CU to warn of a mixed colour installation - you can get those at most electrical trade places.

[ARWadsworth]

The only snag is if the lighting cables are not RCD protected. Sinking the cables (either the old ones or some new ones) would rquire RCD protection to meet the 17th edition regs.

Adam

[Tim Watts]

True.

Do the NIC class "wallpapered over" as "buried"? :-O