Do electrical wires suppling light fittings generate heat?

Question

It would be useful to know before I insulate my loft.

Answer 1

All homes have low level (I.e. Lights) electric wires running around insulated loft spaces, there's no danger in it.  

Answer 2

All cables carrying at or near their current rating will heat up, any insulation will cause more heat, and could soften or damage insulation especially PVC. Cable sizes may need to be uprated or re-routed to compensate. Some guidance here.  http://www2.theiet.org/Publish/WireRegs/...

However if the cables in question do only supply lighting circuits they are unlikely to be fully loaded and should pose no problems, as a shower or cooker cable might!

Answer 3

Yes they do but the heat is negligible.

Edit; Thank you for the Thumbs Down, what would I know?

Answer 4

Yes all wires supply heat (friction) from the electron flow

Answer 5

I cant believe some of these answers, electricity generates tremendous heat, an electric bar fire or a light bulb for eg, try touching them when they have been on for 5 minutes. The same effect takes place when electricity passes down wiring but it is dispersed by the appliance in use which makes up the circuit.

Take the appliance out of the loop and the wiring will burn.

  

Answer 6

the lights would create more heat then the actual wires.

But you should be concerned if there is any heat or hot sockets, as this could be a wiring blunder and the actual wires arent in contact and are sparking, this will generate sufficient heat to cause a fire! so always give your wiring a tug to see if it is secure.

Answer 7

all wires heat up to a certain degree. If the right weight of wire is used then this will not be a problem. Always use a heavier wire if in doubt.

Answer 8

hopefully not enough to matter but they can if they are messed up.  

Answer 9

dependant on the load and cable capacity generally lighting circuits shouldn't generate excessive heat

ensure that you don't cover the lighting circuit cable with the loft insulation

this will cause the cables to heat up

Answer 10

Not perceptibly  no    

Answer 11

No they do not.