Excavation support, as herein described, refers to a temporary shoring system that is built from the top down, a sequence that provides continuous support of the soil as the excavation proceeds.  The excavation support system is designed both for the earth pressure load as well as any surcharge loads within the influence of the excavation.

Often the most economical support system is a soil nail wall or tiedback soldier beam and wood lagging wall.  These systems function to support the surrounding ground during subsurface excavation and only until the basement walls and floor slabs are constructed and achieve strength; at that time the new foundation walls and slabs take over the support which was provided by the excavation support system.  A temporary earth retention system's only purpose is to allow the side of the excavation to be made in a vertical or near vertical cut, avoid disturbance of the site behind the shoring system, and thereby maximize the size of the new building's footprint.