Wooden fire-rated doors are constructed using fire-retardant timber or fire-retardant wood products for the door frame, door leaf frame, and door leaf panel. If the door leaf contains filling material, it must be filled with fire-resistant and heat-insulating material that is non-toxic and harmless to humans. These doors are equipped with fire-rated hardware fittings to achieve a certain level of fire resistance.

The overlap dimension between door leaf and frame shall not be less than 12mm; The clearance on the hinge side between door leaf and frame shall not exceed the dimensional tolerance specified in the design drawings; The clearance on the lock side between door leaf and frame shall not exceed the dimensional tolerance specified in the design drawings; The clearance between door leaf and top frame shall not exceed 3mm; The gap between double or multiple door leaves shall not exceed 3mm; The clearance between the door leaf and the bottom frame or floor shall not exceed 9mm; Clearance between the door leaf and frame contact surfaces: The clearance at the hinge side, lock side, and top frame contact surfaces shall not exceed 3mm; The height difference between the door leaf and frame surfaces: On the opening side of the fire door, the height difference between the frame and door leaf surfaces shall not exceed 1mm.

Wooden fire doors refer to doors where the frame, door leaf skeleton, and door leaf panels are made of wood or wood products, with a fire resistance rating meeting national standards. Minor deviations in wooden fire doors are unacceptable; even a small detail could result in failure to meet national standards. Materials Used

First, comparing the materials used: Fire doors have a simple structure, primarily consisting of four parts: door closers, door panel materials (such as 06 and 08 grades), door frame materials, and fireproof boards. Class A fire doors generally use higher-quality 08 grade materials, with a normal service life of 5-8 years. The iron used in the door panels is thicker, so for doors of the same thickness, Class A fire doors weigh more than Class B fire doors.

Fire Resistance Duration

The fire resistance duration of a fire door is primarily determined by the fireproof board. In this regard, Class A fire doors typically employ fireproof boards with superior performance compared to those used in Class B fire doors, resulting in overall stronger performance. Additionally, Class A fire doors are particularly suitable for applications requiring fine grinding before electroplating, excellent vibration performance, hand tool mirror polishing, and electric heating tube mirror polishing. Examples include vibration finishing for various furniture hardware fittings, cutting and polishing of hand tools, surface vibration finishing for daily consumer products, and bicycle component finishing.

Another noteworthy aspect is the door frame material in Class A fire doors. Since the frame specifications can be flexibly customized according to customer needs, designing door openings becomes more convenient, effortless, and time-saving.

While Class A fire doors carry a higher purchase cost than Class B fire doors, their overall operating costs demonstrate superiority in numerous aspects. However, Class B fire doors retain their cost-effective advantage and continue to serve a segment of the low-end market.