Fire resistant walls typically include a frame assembly formed from a plurality of steel channel studs and cross members as well as a stratum of gypsum disposed on both the inner side and the outer side of the frame assembly. The fire resistant wall typically has a stratum of insulation disposed between the studs. The use of gypsum, which is fire resistant, on both the inner side and the outer side of the frame assembly is a relatively inexpensive construct that is capable of passing standard fire resistance tests. That is, in this configuration, the spread of fire from one side of the wall to the other is resisted for a set period of time. During the test, fire is applied to an “inner” side of the wall, and temperature measurements are taken at a number of points on the “outer” side of the wall. During the test, the inner stratum of gypsum is consumed by the fire over a period of time. Typically, a gypsum stratum, or a portion thereof, remains in tact until water and the gypsum, vermiculite and/or similar material fibers within the stratum are destroyed at which time the gypsum stratum, or a portion thereof, crumbles into dust. The destruction of the inner stratum of gypsum has two detrimental effects. First, and most obvious, with the inner stratum gone, the fire may spread to the insulation and outer stratum of gypsum. Second, when the inner stratum is destroyed, structural support for the frame assembly is removed. To pass the test, a fire resistant wall must both delay the spread of the fire for a set period of time (as measured by sensors on the outer side of the wall and which must detect a temperature above a predetermined limit) and ensure that the elements of the frame assembly can survive a fire hose test. That is, after the test, elements of the frame assembly must be able to withstand the force created by a fire hose.
The use of both an inner and outer stratum of gypsum held ensures that the frame assembly will not collapse when the stratum layer of gypsum is consumed by the fire. That is, the outer stratum of gypsum adds rigidity to the frame assembly even when the inner stratum of gypsum is destroyed. Further, as noted above, gypsum is fire resistant and helps delay the spread of the fire. This construct, however, tends to be thick. Thus, each wall occupies a set amount of floor space that could be used for other purposes.
Further, the use of steel channel studs, while sufficient for supporting a fire resistant wall, does not have sufficient strength to create a blast resistant wall. Blast resistant walls are required in certain types of construction such as, but not limited to, hazardous material storage. Tubular steel studs increase the strength of the frame assembly, but are known to trap heat within the members. Given that the most elements of the fire resistant wall are coupled directly to the frame assembly, this allows heat to be transferred via conduction from one side of the wall to the other. This is not a desirable effect.
The insulation used in the intra-stud spaces has not necessarily been a fire resistant material. For example, fiberglass insulation melts at about 1000 degrees Fahrenheit. Typically, the insulation is selected for the insulative qualities of the material. Thus, during a fire, before the inner stratum of gypsum is breached, the insulation burns. Thus, when the inner stratum of gypsum is heated, the heat is passed into an, essentially, empty space. This heat is then transferred to the inner side of the outer surface and may cause the outer layer of gypsum to overheat.
Further, it is noted that the gypsum strata is typically composed of a plurality of panels. During a fire these panels tend to shrink and gap. That is, as water and other materials within the panel are consumed, a gap may appear between adjacent panels. Such a gap allows the fire to pass into the fire resistant wall and consume the insulation and/or heat the frame assembly. Again, this is not a desirable effect.
USPTO Backgrounds
USPTO Backgrounds