Convection Draughts

If you feel a draught down your neck when seated against a cold external wall or window then that’s reason enough to insulate it. The science behind the affect is very simple, as  air is warmed it becomes lighter in weight, so will naturally rise. It then comes in contact with a cold external surface, window or wall, cools down, now becomes naturally heavier, therefore falling down the window or wall. As the air falls it comes in contact with even colder air, speeding up its decent rate as it falls towards the bottom of the window or wall. The now colder air and its falling movement is felt as draught. By insulating the walls and making them warmer the effect is eliminated.