The Earthbound Seismic Holdown System Description: Current seismic holdown systems help prevent the "uplift" that separates a wood frame building from its foundation during an earthquake.

The problem is that when used on wood framed buildings, the existing conventional holdown systems do not account for shrinkage or compression in the wood members.

The Earthbound System contains innovative patent pending methods and patented shrinkage compensating devices. An anchor bolt in the foundation is connected to a threaded rod that runs through the load bearing or shear walls of the structure. The application of the Impasse Device is used every floor (the load application of the Impasse Device can skip floors depending upon the load requirements) to connect the rod sections and allows for shrinkage movement in the structure.

At the top of each holdown run an Impasse Device serves as the completed connection effectively creating a continuous steel rod connection through the structure.

Through the use of the Impasse Device in the Earthbound System, the system will keep working to keep a tight seismic connection even after gypboard or sheetrock is in place.

Through testing at the Civil Engineering Structures Research Lab at the University of Washington, we have determined that the Earthbound System will also keep working to keep system tightness during a seismic event.