Boxing in cables and insulating over the top

[paulramplin]

I'm trying to figure out a way to insulate my loft better.... but there are wires EVERYWHERE!!
So I'm wondering whether it would be easier to simply box in the wires (say, under loft boards) and then insulate over the top? Obviously I would only do this if it's safe to do so - so I need to know if it is safe, and if so, how much space to allow beneath the loft boards where the cables are?
Thanks in advance.

 

[PrenticeBoyofDerry]

Electrical regulations, concerning grouping of cables in containment, access to hidden joints (If any?), also protection against mechanical damage and factoring in that they are enclosed in a thermal zone. All need to be considered.