Fire Door Ratings and Classified Openings

Date:May 18, 2020

90 Minute Fire-Rated Door

3 Hour Fire-Rated Door

          90 Minute Fire-Rated Door                                                                              3 Hour Fire-Rated Door

Narrow Vision Lite on KD Drywall Frame – Finished                            Flush Door on Welded Masonry Frame – Unfinished (Primed Gray)


Fire door openings are classified by their locations in a building. Location determines the length of exposure protection required, based on the potential fire hazard of that particular area. The opening classifications are shown below. Fire-protection ratings tested and classified by: Warnock Hersey-WHI or Underwriters Laboratories- UL. The local Authority Having Jurisdiction must be the final authority on fire door assembly issues.

Note: Most exterior doors do not require fire rating, unless there is the potential for fire exposure from the outside of the building. 

See Flush Metal Doors for non-rated doors, which are made from the same construction as a fire-rated metal door.

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