Building Code – Fire Wall Construction
The International Building Code (IBC) identifies three types of walls used for fire separation of areas within a building. These three wall types are Fire Walls, Fire Barriers, and Fire Partitions. The use of these walls is dependent upon the occupancy separation required by the IBC and whether a fire sprinkler system is provided/required.
The Fire Wall is the most restrictive of the wall types in the IBC, by creating a complete separation of the building based on the allowable building area, allowable building height, and type of construction. One goal of this system is to restrict the spread of smoke and fire within one building. The Fire wall is designed and constructed so that the structure on either side of the fire wall will collapse without the collapse of the wall under fire conditions. The fire resistance rating of the Fire Wall can range from 4 hours to 2 hours, based on Occupancy Group of the building. The Fire wall will be continuous and extend not more than 18 inches beyond the exterior surface. This extension is intended to stop the potential fire from traveling from one building to the other around the fire wall. The Fire Barrier are wall types that that provide a higher degree of protection than fire partitions. The fire barriers are used for separating exits, exit passageways, incidental use areas, shaft enclosures, separated occupancies, and fire areas. Fire barriers also include interior walls that subdivide a space into adjacent fire areas. The fire resistance rating of the Fire Barrier can range from 4 hours to 1 hour, based on the Occupancy Group of the building. Fire Barriers extend from the top of foundation or floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above. The joints at the intersections of the fire barrier walls must be sealed with a fire-resistance joint system (caulking). The Fire Partition are wall assemblies that enclose an exit access corridor, separate dwelling units in the same building, corridor walls, and tenant spaces in malls. Fire partitions have a fire-resistance rating of not less than 1 hour. Fire barrier corridor walls can have less than 1 hour, depending on Occupancy type and sprinklered building. Fire Partitions extend from the top of foundation or floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above. The Fire Wall is the most restrictive fire rated walls because of the requirements to separate the building within fire areas and provide a continuous fire rating from the foundation to the roof. The Fire Barrier is less restrictive than the Fire Wall in that it will provide a rated wall around shafts and separation of Occupancy Groups within a building. The fire barrier wall will be continuous from the floor through the concealed space at each level. The fire partition is the least restrictive fire rated wall system used in fire rating corridors and separation of dwelling units.