Underpinning

Underpinning

Underpinning is a means of extending an existing buildings foundation to a lower elevation.  This can be accomplished by digging pits in a sequenced construction process below an existing buildings foundation and filling the pits with concrete. Load is developed in the pins by drypacking between the footing and pin, or if necessary jacking. Piles, drilled or jacked, can be installed to bypass a unsuitable soil layer and attached to the existing buildings foundation.