Described are heat insulation structures for a garment. The heat insulation structure includes at least one first insulation element having a first uncompressed shape, at least one second insulation element having a second uncompressed shape that is different than the first uncompressed shape, and a contact area formed when the first uncompressed shape contacts the second uncompressed shape. The second uncompressed shape is deformable through pressure applied by a wearer's body when the garment is worn, which increases a size of the contact area.