Plenum insert for seat and method of its fabrication

A method of fabricating a seating comfort system plenum insert for insertion into a vehicle seat, the method comprising:

• providing an outer material layer of a non-permeable single or multi-layer film having an edge;
• providing an air-permeable inner spacer layer;
• placing the air-permeable inner spacer layer on the outer material layer;
• folding the outer material layer over the air-permeable inner spacer layer such that the edge of the outer material layer overlaps itself and comprises an overlapping edge;
• and
• sealing the overlapping edge of the outer material layer around to air-permeable inner spacer layer and forming a folded over sealed insert having a sealed edge that is sealed about an entirety of a periphery of the folded over sealed insert.