what is a fire rated door frame | LONGXUAN Guide

What is a Fire-Rated Door Frame?

A fire-rated door frame is a critical component of a fire-rated door assembly, designed to contain fire and smoke for a specified period. It's not just about the door itself; the frame plays an equally important role in preventing fire from spreading. These frames are constructed from materials that can withstand high temperatures and maintain their structural integrity during a fire. A fire-rated door frame ensures that the door assembly functions as intended, providing valuable time for evacuation and fire suppression.

What are the different fire ratings for door frames?

Fire ratings for door frames are typically expressed in hours (e.g., 20 minutes, 45 minutes, 60 minutes, 90 minutes, or 3 hours). These ratings indicate the amount of time the door and frame assembly can withstand fire exposure during a standardized fire test, such as those defined by UL (Underwriters Laboratories) or NFPA (National Fire Protection Association). Common ratings include:

• 20-Minute Fire-Rated Frames: Suitable for areas with low fire hazard, such as some interior offices or residential spaces.


• 45-Minute Fire-Rated Frames: Often used in corridors and smoke barriers.


• 60-Minute Fire-Rated Frames: Commonly found in stairwells and exits.


• 90-Minute Fire-Rated Frames: Frequently used for fire walls separating different occupancy areas.


• 3-Hour Fire-Rated Frames: Typically used in fire walls that require a high level of fire protection.

It's crucial to consult local building codes and regulations to determine the required fire rating for specific applications. These codes often specify the minimum fire rating for door frames based on the building's occupancy, size, and location within the structure.

What materials are used to make fire-rated door frames?

Fire-rated door frames are typically made from steel, hollow metal, or engineered wood. The material selection depends on the required fire rating, the door's weight and size, and aesthetic considerations.

• Steel Frames: Steel frames are a popular choice due to their strength, durability, and fire resistance. They can be fabricated to meet various fire ratings and are suitable for heavy-duty applications. The steel gauge also plays a vital role, with thicker gauges offering greater fire resistance. For example, 16-gauge steel is frequently used in 90-minute rated frames. Hollow metal frames, a type of steel frame, are often filled with a fire-resistant core material to enhance their performance.


• Hollow Metal Frames: These frames offer excellent fire protection. They can be filled with materials like mineral wool or gypsum-based compounds to improve insulation and prevent heat transfer.


• Engineered Wood Frames: While less common than steel, engineered wood frames are sometimes used in fire-rated assemblies, especially when aesthetics are a primary concern. These frames are treated with fire-retardant chemicals and designed to maintain their structural integrity for a specified time. The wood must meet strict standards and be part of a tested and listed fire-rated door assembly. Fire-rated wood frames often require intumescent strips, which expand when exposed to heat, sealing the gap between the door and the frame.

How are fire-rated door frames installed?

Proper installation is paramount for a fire-rated door frame to perform as intended. Installation should always adhere to the manufacturer's instructions and the guidelines outlined in the fire-rated door assembly listing. Key steps include:

• Frame Preparation: Ensure the opening is plumb, square, and of the correct size. Check for any obstructions or damage that could compromise the installation.


• Anchoring: Use appropriate fasteners (e.g., screws, bolts) that are specifically listed for use with fire-rated door frames. The type and spacing of fasteners are critical for maintaining the frame's integrity during a fire.


• Shimming: Shim the frame as necessary to ensure it is level and plumb. Gaps between the frame and the wall should be filled with fire-rated caulk or sealant.


• Hardware Installation: Install all required hardware (e.g., hinges, latches, closers) according to the manufacturer's instructions and the fire-rated assembly listing. Use only hardware that is listed and approved for use with the specific door and frame.


• Clearances: Maintaining proper clearances between the door and the frame is crucial. Gaps that are too large can allow fire and smoke to pass through. Check the fire-rated listing for the maximum allowable clearances.

Improper installation can significantly reduce the fire resistance of the door assembly, rendering it ineffective in a fire situation. Always use qualified installers who are familiar with fire-rated door frame installation procedures.

What are the code requirements for fire-rated door frames?

Fire-rated door frame requirements are dictated by various building codes and standards, including the International Building Code (IBC), NFPA 80 (Standard for Fire Doors and Other Opening Protectives), and local building codes. These codes specify the minimum fire rating for door frames based on the occupancy and location within the building.

Key code requirements include:

• Fire Rating: The required fire rating depends on the location of the door and frame within the building. Fire walls, fire barriers, and smoke barriers have different fire rating requirements. Consult local codes for specific requirements.


• Listing and Labeling: Fire-rated door frames must be listed and labeled by a recognized testing laboratory, such as UL or Intertek. The label provides information about the fire rating and the manufacturer's identification.


• Hardware: All hardware used in a fire-rated door assembly must be listed for fire door applications. This includes hinges, latches, closers, and other components.


• Clearances: Codes specify the maximum allowable clearances between the door and the frame to prevent the passage of fire and smoke.


• Installation: Installation must comply with the manufacturer's instructions and the requirements of the applicable building code.

Compliance with these code requirements is essential to ensure that fire-rated door frames provide the necessary fire protection and meet the legal and safety standards for the building.