Project: Mercer Island Residence
Solution: The house was lifted and secured on cribbing in order to remove the West foundation wall. Per Geotech and Structural Engineer design, helical tiebacks were installed through the uphill side of the East foundation wall securing the home to the hillside. Installed vertical helical piles to support the East foundation wall. Installed helical tiebacks at each vertical pile to secure them to the hillside.
Challenges: The project’s location and condition of the site required a complex design by the Geotech and Structural Engineers to accomplish the desired expansion. Being performed in November, the hillside runoff was unusually high making It necessary to pump water out of the excavated areas where helical piles were placed. The necessary location of cribbing support limited the job site workspace.
Results: Hillside home was successfully supported allowing the needed excavation to safely create an additional living area in their basement.