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1.5 hours of Protection - 90 Minute Fire rated Doors

Posted by Lee Lumber on Dec 14, 2016 8:00:00 AM

Screenshot 2016-12-09 14.56.31.png90 minute fire rated doors are one of the six types of doors specifically designed to withstand fire for a specified amount of time. Doors are instrumental in giving people adequate time to escape a fire. Constructed of several different types of materials, the core of the 90 minute fire door is what provides an hour and a half of safety.

Composition of a 90 Minute Fire Door

Fire doors are typically made from several different materials. The most common materials used for fire doors include the following:

  • Aluminum
  • Glass
  • Gypsum
  • Steel
  • Vermiculite
  • Wood

While the core of the door must be strong, the frame is also made of these materials to ensure that the door can be held in place in the event of a fire. This means that the doors are typically sold pre-hung. Both the door and the frame must meet certain construction standards to gain the certification to be considered fire doors.


Ultimately, the door is only as good as the installation. A 90 minute fire door that is improperly installed cannot be guaranteed to provide the specified amount of time.

Installation goes beyond the process of actual placement as well. The area around the door must all be conductive to securing the area. For example, if there are large gaps around the door or incorrect carpeting, this can negate many of the benefits of a well crafted and installed fire door. This means that you have to consider more than just the door and frame when making your selection. 


Because the doors are highly specialized, only a few companies produce and sell them. You can find the best fire doors from the following companies:

Take your time to review each door because different companies have different specifications that they aim to meet. Some go well beyond just providing fire protection.  Also be aware of your local building codes as they may require different ratings for different applications.  For example, Chicago requires at least 90-minute fire rated doors.

And note that any preparation for hardware needs to be done by a shop or manufacturer that is licensed to do so and they will provide the Underwriters Laboratory or Warnock-Hersey Fire-Rated Label that must be present for acceptance by Building  and Code Inspectors. 

Visit our website for more information on fire rated doors and all the doors we have at Lee Lumber.

Looking for more home improvement ideas?  Check out our comprehensive e-book on home projects with great ROI (return on investment):

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Topics: Doors

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