Photo courtesy AGC of Washington The Northwest School was renovated and expanded while it was occupied.

Renovation and expansion of The Northwest School took place while the school was occupied, making it important for Lease Crutcher Lewis to maintain a quality learning environment for the students.

Soil injection grouting was used for underpinning and soil stabilization instead of a more costly shoring solution. The technique allowed excavation straight down from the four-story north exterior wall of the existing school with an overall deflection of 1/8-inch or less, with no damage to the existing finishes. The process also was safer for the students.

To overcome the tight, confined work space, Lease Crutcher Lewis located a mobile crane in the middle of the building footprint and built around it, leaving enough of the structure out so the crane could be removed later.

There were 24,762 worker hours and zero accidents.