Arvada Excavating Company has been doing sub-excavation for large residential and building projects, since it became the standard on most projects in the mid 1990’s. This process involves the removal and replacement of normally 10 to 12 feet of soil below the lowest part of the foundations. Once the soil is removed to the required depth, the grade is certified by a surveyor. The material is then replaced in thin lifts with a high water content and a complete mixture. This is done to reduce the risk of damage to structures due to the swelling soils in our region.