Yes, that's part E, not L, M, or P! ?
Scenario is studding wall between a landing and a bathroom. I don't suppose that anybody in the bathroom will be perturbed by noises on the landing, but one doesn't necessarily want to hear various splashings.
So we have a 2nd floor ring final coming and going in the wall along with the lighting circuit.
I may be a bit thick, but I don't find the Part E Approved Document easy to interpret. If any wadding is to be put into the wall, then we potentially end up with Reference Method A, in which case the 2.5 mm2 cable is downgraded to 20 A. At this stage I want to ignore the possibility that two legs of a ring should be derated due to grouping.
My feeling is that the requirements of Part E can be met without recourse to wadding, but what I would like to know is whether any of you have encountered this problem, and if so, how you have addressed it. Many thanks. ?