Dwellings are subject to both lateral and vertical loads. Lateral loads include wind and seismic forces. Examples of vertical loads include the weight of the structure itself, the furnishings, and snow on the roof. To address relevant life-safety issues, dwellings are laterally braced to prevent collapse and failure caused by a wind or seismic event. Chapter 6 of the International Residential Code describes a variety of acceptable methods that may be used to brace a dwelling.
Gypsum board has historically been used as a bracing element, either alone or in conjunction with other materials. While its use as a bracing element reflects the widespread application of gypsum board as a finish material, it also points out the strength of gypsum board as a structural element; an attribute that is often understated or overlooked.