Draughtproofing behind kingspan and skirting board and wall?
I was going to use my old skirting boards
in front of the new kingspan insulation
but I've noticed that behind where the skirting boards was
is a gap which goes down behind the floorboards
and a draught whistles up it from downstairs...
Should I somehow seal the gap with some plastic
so the draught cant go up behind the kingspan,
or use doublesided sticky tape or what to stop the draught?
picture is at