Material that provides the best insulation includes - Fiberglass, Rock wool, Cellulose, Polyurethane foam, Extruded polystyrene foam (XPS), Expanded polystyrene foam (EPS or beadboard), polyisocyanurate foam, Vermiculite. Aluminium foil, also called the tin foil, makes an excellent insulator. Fireproof insulation materials greatly increase your ability to escape a fire. Fireproof insulation materials come in five primary forms. These include chopped fibres, foam, fibrous mats and textiles, board or block insulation, films and foils. The best insulator in the world right now is most probably aerogel, with silica aerogels.