Running 2.5 mm2 T&E on top of floor insulation

[Luka]

I have decided to insulate my ground floor suspended joist floor in the living room using 140mm of rockwool duo slab (R-value 4.1 m2.K/W).

2.5 mm2 T&E is currently running under the floor and I want to place it on top of the insulation (not to bury it in) and directly under the subfloor. Will current capacity be affected to the level I need to be concerned about? Should I place it in a conduit or maybe lay it on some kind of tray to keep it vetilated and prevent it from sinking into the insulation? Optionally, since I have access to it, would it be a good idea to replace it with 4mm2 T&E or would that be overkill? It is a ring circuit with 32A breaker).

 

[Luka]

I have decided to insulate my ground floor suspended joist floor in the living room using 140mm of rockwool duo slab (R-value 4.1 m2.K/W).

2.5 mm2 T&E is currently running under the floor and I want to place it on top of the insulation (not to bury it in) and directly under the subfloor. Will current capacity be affected to the level I need to be concerned about? Should I place it in a conduit or maybe lay it on some kind of tray to keep it vetilated and prevent it from sinking into the insulation? Optionally, since I have access to it, would it be a good idea to replace it with 4mm2 T&E or would that be overkill? It is a ring circuit with 32A breaker).

After consideration, the other option would be running the cable under the insulation, possibly in a conduit (unless a conduit is not required) directly on the galvanised mesh supporting the insulation, so it would not be covered by anything from the bottom. Would that be a better option as cable would be protected from mechanical damage by nail/screw to the floor? Again, will current capacity be affected to the point where some action is required? Thanks