Did you know that it wasn’t until after the 1980s that fire barriers and fire walls became a standard requirement for the International Building Code (IBC)? Fire barriers and fire walls are similar, but differ in their specific functions.
Fire barriers are interior walls, ceilings and/or floors designed and constructed to be fire resistant in order to prevent the movement of fire and restrict smoke from spreading. Fire barriers may also be non-structural, such as radiant energy shields and raceway fire barriers. Fire barriers, at minimum, have a one-hour fire resistance rating, meaning that they will contain the fire for at least one hour. This gives building occupants a chance to escape, and for first responders to put the fire out before it causes damage to additional areas of the building.
Fire walls, as defined by the IBC, are “A fire-resistance-rated wall having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall.” They are typically used to subdivide a building or to completely separate adjoining buildings to resist the spread of fires. The concept originated in densely populated areas where buildings were constructed close together, and a fire in one could mean disaster for neighboring structures. A fire wall contains a fire within the area in which it originated. Openings in fire walls must utilize specific materials and design. Fire walls not only contain the fire, they are designed to withstand force from other structures or items that may collapse within the building, such as inventory or storage.
|Summary of Differences|
|Fire Barrier||Fire Wall|
|Continuous from floor through concealed space at each level||Walls that extend from the base of the building to the roof. Continuous from exterior wall to exterior wall.|
|Interior barriers used in shafts and areas where occupancy is different from adjacent areas||Used to create separate areas that require a higher level of fire safety and structural integrity. Each portion of a building separated by fire walls can be considered a separate building.|
|1-4 hour fire resistance rating||2-4 hour fire resistance rating|
|Commonly used in shaft enclosures, exits, fire areas||Designed to provide additional structural stability so as not to collapse|
|More leeway in acceptable openings or penetrations||Openings or penetrations are protected and limited|
Both fire barriers and fire walls are important to a building’s fire protection system, as they are designed to contain the fire to one location. Different occupancy categories may carry different fire rating requirements (ie, hours). The building’s occupancy, size, and configuration determine whether fire barriers or fire walls are required. Encorus Group can help you figure out which you will need – give our fire protection engineer Andy Wiedemann, PE a call at 716.592.3980, ext. 154, or email him at [email protected].