what is fire rated door made of | LONGXUAN Guide

What Is a Fire Rated Door Made Of?

Fire rated doors are specially constructed doors designed to resist fire and prevent its spread for a designated period, commonly ranging from 20 minutes up to 3 hours. They are crucial in ensuring safety within buildings by compartmentalizing areas and allowing safe evacuation during fires. Understanding the materials and construction methods used in these doors is essential for professionals in the wood door industry.

1. What Materials Are Used in Fire Rated Wood Doors?

Fire rated wood doors are generally composed of a specially treated core and protective facings. The core materials can include:

• Mineral Core: Non-combustible mineral-based cores such as gypsum or perlite, which provide excellent fire resistance by acting as heat barriers.
• Stave Core: Vertical wood staves glued together with fire-retardant adhesives, often combined with a mineral core for improved fire resistance.
• Particleboard Core: High-density particleboard with fire-retardant additives used in some fire doors rated for lower time spans.

The facings are typically made of hardwood veneer, plywood, or steel sheets, often bonded to the core with fire-resistant adhesives. The edges may include intumescent seals that expand when heated to seal gaps and prevent smoke passage.

2. How Is Fire Resistance Achieved in Wood Doors?

Fire resistance in wood doors is achieved through a combination of core composition, facings, and intumescent seals. The core material must slow heat transfer and resist combustion, while the facings add structural integrity. Intumescent strips around the edges expand under heat, closing gap spaces and enhancing the door's effectiveness against fire and smoke.

3. What Are the Fire Ratings for Wood Doors?

Fire rated doors are classified based on the duration they can withstand fire exposure, commonly:

• 20 minutes (FD20)
• 30 minutes (FD30)
• 60 minutes (FD60)
• 90 minutes (FD90)
• Up to 180 minutes (FD180), though less common for wood doors due to material limitations.

The rating corresponds to standardized test results, such as those defined by UL 10C or BS 476, and must comply with building codes.

4. What Standards Govern Fire Rated Wood Doors?

Fire rated wood doors must meet rigorous national and international standards, including:

• ANSI/UL 10C: Standard for Fire Tests of Doors and Other Opening Protectives in the United States.
• NFPA 80: Standard for Fire Doors and Other Opening Protectives.
• BS 476 Parts 22 and 24: Fire resistance tests used in the UK and other regions.
• EN 1634-1: European test method for fire resistance of doors.

Adhering to these standards ensures performance reliability and compliance for fire safety.

5. How Should Fire Rated Wood Doors Be Maintained?

Maintaining fire rated doors involves regular inspection and upkeep to ensure functionality:

• Check intumescent seals and replace if damaged or missing.
• Ensure door fits properly within the frame and closes fully without obstruction.
• Avoid modifications that may compromise the door’s integrity, such as drilling holes or changing hardware not rated for fire doors.
• Clean the door surfaces with appropriate materials and avoid harsh chemicals that could degrade protective coatings.

Proper maintenance prolongs the door’s fire resistance and compliance with safety standards.