Fire door manufacturers commonly use materials such as timber, steel, gypsum, and glass to construct fire-resistant doors. Timber is often treated or combined with fire-retardant cores, while steel doors provide high durability and resistance. Gypsum is used for its excellent insulation properties, and fire-rated glass allows visibility while maintaining protection. Fire door manufact... https://www.vijaysystems.com/fire-doors-and-partitions.php