Insulation and wiring

[Ed21]

I understand that wires covered in insulation means reducing the load, but what  if it's through the insulation? 
Got some wires that need to go through 50mm or 75mm Celotex.

What's the SOP?
Is it ok to seal the gap around the wires? 

Ed 
 

[markc]

If you are going straight through, then the length of cable covered by the insulation is short and will not cause overheating, so yes its ok to seal around the hole.

[Ed21]

Ok cheers for that Mark ?