The Watson residence is located on a steep slope in Seattle, WA. The home’s new foundation required both vertical support and lateral support to help stabilize the Environmentally Critical Area (ECA). Pile King’s ability to crane-in Bobcat sized equipment onto the steep slope achieved substantial savings for the customer. Furthermore, equipment installations, compared to man-portable installations, provided the opportunity to achieve deeper penetration into the more stable substrata and therefore a better end-product.
McDowell NW Pile King installed 73 each 3” dia. sch 40 pipe pile driven to approximately 24’ each with a 6 ton design load. Three load tests were performed on production piles to ensure pile capacity had been met. Also, five each 2-7/8” diameter shaft helical anchors with 10” & 12” helical plates were installed. Anchors attained a 5 ton design load, drilled at 20 degrees from horizontal and 15’ overall length. Both the pipe piling and the helical anchors were cast into the grade beam foundation system. This job was a unique application of utilizing both driven pipe pile for vertical loads and helical anchors drilled horizontally for lateral loads. McDowell Pile King has earned the reputation for finding creative ways to get the job done and ultimately save our customers money.