Fire door size
2025-11-30
Fire door size : No "Standard Size," Only "Code-Compliant Dimensions"
Unlike ordinary interior doors, fire doors do not have a unified "standard size." Their dimensions must comply with national fire protection technical codes and be certified by the National Fire Product Testing Center. The specific dimensions are clearly marked on the fire door's identification label (the red "S" mark).
一、Common Fire Door Size Ranges (For Reference)
Although sizes are not fixed, certain ranges are very common in practical projects:1、Single-Leaf Fire Door:
Width: Common widths include 30，32,36,and42 inches,along with various
Height: 80inches (2032 mm) and 84 inches(2134mm) are very common
Common Specifications: 900mm × 2000mm, 1000mm × 2100mm, etc.
2、Double-Leaf Fire Door (with one active leaf and one smaller inactive leaf):
Width: Commonly 1200mm, 1500mm, 1800mm
Height: Commonly 2100mm, 2300mm
Common Specifications: 1500mm × 2100mm, 1800mm × 2300mm, etc. The width of the active (larger) leaf is generally not less than 900mm.
3、Double-Leaf Fire Door (two equal leaves):
Width: Commonly 1200mm, 1500mm, 1800mm, 2400mm
Height: Commonly 2100mm, 2300mm, 2400mm
Common Specifications: 1200mm × 2100mm, 1500mm × 2300mm, etc.
Note: The above dimensions are only common ranges. Actual project sizes may be larger or more specialized based on the opening size and design requirements.
二、 Key Factors Determining Fire Door Size
1、Building Opening Size:
Fire doors are installed in pre-set door openings in the building. Designers determine the minimum width based on codes and then design the opening size in combination with building modules and practical usage needs (e.g., whether equipment needs to pass through).
The actual manufactured size of the fire door = Opening size - Installation gap.
2、Usage Function and Location:
Evacuation Routes, Stairwells: Typically use single-leaf or double-leaf doors with one inactive leaf. The width must meet personnel evacuation requirements.
Equipment Rooms (e.g., electrical rooms, fan rooms): May require wider doors for equipment access, often using double-leaf doors or doors with an inactive leaf.
Large Warehouses, Industrial Plants: May require extra-large fire shutters or double-leaf/multi-leaf fire doors.
3、Fire Resistance Rating:
While the fire resistance duration differs for Class A (1.5h), Class B (1.0h), and Class C (0.5h) doors, this does not directly determine their size. Fire doors of any class can come in different sizes. The size is primarily determined by evacuation requirements, while the class depends on the required fire resistance time for that location.
三、Important Considerations
1、Concept of Clear Width: The width required by the code refers to the "clear width," which is the effective width available for passage when the door leaf is fully open. For doors with an inactive leaf, where usually only the active leaf is opened, the evacuation width calculation must be based on the clear width provided by the open active leaf.
2、Do Not Alter Arbitrarily: The dimensions, class, and material of a fire door that has passed fire acceptance inspections are legally mandated. It is strictly forbidden to remove, replace, or modify them without authorization. Unauthorized alterations will nullify their fire resistance function and violate fire safety laws.
3、Consult Professionals: When renovating or remodeling, if you need to install or replace a fire door, be sure to consult the building design unit or a professional fire protection engineering company to ensure that the selected fire door's dimensions and class fully comply with current fire codes.
Summary
The dimensions of a fire door are determined collectively by the evacuation width requirements stipulated in the "Code for Fire Protection Design of Buildings," the actual building opening size, and usage needs. Before purchasing and installing, the safest approach is to measure the width, height, and wall thickness of the door opening, and then consult a qualified fire door manufacturer or fire protection engineering company. They can provide you with a compliant, certified product based on the codes.
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