Extra cable lengths to allow for insulation depth.

[mointainwalker]

Given all the questions about cables being covered with insulation in lofts, can I ask how this is dealt with in new-builds ? Instead of being attached to joits as previously, are cables now loose-laid in conduit on top of the insulation ?

 

[flameport]

They are still attached to the joists, since cables in a loft will inevitably be for lighting circuits, and even with 1mm cable totally covered with thick insulation, the rated capacity is still more than 6A.

 

[RF Lighting]

If you need to keep cables out of insulation to avoid derating then you can either clip them to the underside of the rafters well above the insulation, or you can install something like this: