To securely fix a heat insulation element to the external face of a constituent part even if a large lateral displacement of the heat insulation element arises by providing a flexible retaining strip between the receptacle and the head.

A nail 13 disposed in a guide pipe having an outer diameter suitable for the inside diameter of a receptive hole 18 is driven into a constituent part 8 by an explosive power. The diameter of the expanded end area 21 of the nail 13 is made equal to the diameter of the receptive hole 18. A corrugated element 16 disposed between the expanded end areas 21 of the radially expanded nail 13 is axially pressed on the external face of the constituent part 8. Thereafter, the head 2 is led along retaining strips 3, 4 toward the receptacle 1 to a contact position of the heat insulation element 7 and brought into pressure contact with the external face of the heat insulation element 7. The loose end of the retaining strip 3, 4 is grasped by hand to give a tension. After the head 2 is fixed, the end of the retaining strip 3, 4 projecting from the head 2 is cut off.