Insulation element, expanded insulation element, use of same and method for insulation

An expandable insulation element for the acoustic insulation of an opening and/or of a cavity in a vehicle or building, comprising:

• a carrier element and an expandable material, wherein the carrier element has a plurality of through-holes, wherein, in a non-expanded state, only one surface of the carrier element is at least partially covered with expandable material, and the expandable material at least partially fills the through-holes, wherein, in an expanded state, the expandable material is expanded onto peripheral areas of another surface of the carrier element opposite from the surface of the carrier element which is at least partially covered with expandable material, wherein 50% to 95% of the other surface is covered with expanded material.