The Instant Gusset (1) is an innovative retrofit connector that permanently connects intersecting structural members on a building, helping create homes that are stronger and more resistant to earthquakes and wind storms.
During an earthquake, the floor, wall, and roof diaphragms undergo shearing and bending. Recent studies of hurricane damage on wood-frame buildings indicate that extensive damage was generated by strong winds when the walls moved away from the foundation, and adjacent walls moved away from each other. Steel connectors, between horizontal (H) and vertical (V) components of a wood-frame building’s super-structure, provide continuity so that the building will move as a strong unit in response to seismic or wind activity.
After the destruction caused by the 1994 Northridge Earthquake, building codes were changed. A cripple wall, the wall between the foundation and first floor, receives most of the earthquake force on a building. Cripple walls have to have plywood installed with a concentrated nailing pattern to make them into a shear wall. But many homes use lattice for ventilation in the cripple space and either don’t install plywood or install plywood and then cut holes for ventilation. It seems that every government agency, every engineering firm, and makers of earthquake clips say to install plywood on the cripple walls. The thickness, density, and nailing pattern of the plywood can determine if the installed plywood makes a true shear wall, but the Instant Gusset can make plywood-sheathed shear walls obsolete.
An effective horizontal force-resisting system requires a continuous load path. The load path is a chain that is only as strong as its weakest link. Many structural members of existing homes have been altered by contractors, plumbers, and electricians. The Instant Gusset adds physical integrity to vertical and horizontal structural members.
Most contractors understand gravity well, but rarely wind and seismic forces that can act on a home. Gravity loads from the floor are transferred to the cripple walls, and then down to the foundations where they are resisted by the soil below them. But seismic forces are transmitted up and wind forces are transmitted latterly. The Instant Gusset can absorb and transfer gravity, wind, and seismic forces back to the ground.
Wind storms can occur in every state. And the revised earthquake map of the U.S. by the USGS shows many locations have moderate to high risk for seismic activity.
Requiring no carpentry or exact measurements, the instant Gusset can be installed using screws and a powered drill. Every structural member that intersects another structural member at a right angle can be reinforced with an Instant Gusset.