Fire rated doors, door frames, and door hardware play a crucial role in keeping building occupants safe while minimizing property damage in case of a fire. Different components of door assemblies are rated to withstand fire for very specific periods of time, among which include doors, door frames, window frames, transoms, hardware, glazing, and sidelights. There are major differences between fire rated, listed/approved, and labeled door products. Fire rated products, for instance, are those that have been approved by industry standards to withstand fire for specific periods of time. Fire listed or approved products on the other hand, have been tested and approved via listing agencies. Labeled products physically bear fire rating labels from approved agencies.
Fire rated door assemblies can be classified into 5 different ratings according to the period of time they can withstand fire. This includes 20-minute, 45-minute, 1-hour, 1½-hour, and 3-hour ratings. These ratings are granted by testing agencies, which then label the products according to their approved rating. Doors are required to meet the standards of International fire and building codes, along with other safety authorities and organizations. Building codes also dictate fire rating requirements for adjacent walls, based on their location and other factors like building use. The wall’s fire rating directly affects the required fire rating of the door to be installed. Proper fire doors require positive latching and self-closing mechanisms, among other assembly components.
Fire rated louver doors are ideal because they have a high maximum rating of up to 90 minutes (1 ½ hour-rating). However, this type of door isn’t generally allowed in corridor openings. Custom fire rated doors are advised for very specific building requirements. Most custom fire rated doors come in a variety of core types, including honeycomb, steel stiffened, polystyrene, and temperature rise, which minimize heat transfer and are best used in stairwells of tall buildings.