Foundation problems should be addressed as soon as they are discovered and before the damage is irreversible. The two most common types of foundation failures are foundation settlement (vertical movement of the footers) and foundation wall bowing (lateral movement of below-grade walls).
Typical signs of foundation settlement are stair-step cracks and vertically sheared bricks or blocks. The direction of the cracks is very important in determining whether the foundation wall movement is vertical or lateral (bowing) as the remediation design is entirely different.
The most common and typically most economical method of repairing failed foundations that have settled is to install a series of steel underpinning piers below the affected foundation area. The concept is founded on the principle of turning or pushing an anchor into stable subsoil strata until the torque or pressure applied indicates that the necessary load capacity has been achieved. The load-bearing steel shafts are screwed into the ground independent of the structure and their bearing or holding capacity is verified as the system is installed.
Adjustable brackets are then attached to the base of your foundation walls, connecting the anchors to the foundation. The weight of your home is then shifted to the anchors. In the process, foundations, walls and floors are repositioned (i.e. “jacked up”) and retained from further movement.
Bowed Foundation Walls
Bowing walls will commonly have a long horizontal crack starting 3 to 6 feet from a corner foundation to the opposite corner of the same wall and terminate into stair-step or diagonal cracks leading to the ceiling or floor.
The three most common remedial methods of stabilizing bowing walls are installing a series of (1) vertical strut or I-beams, (2) wall anchors or dead-man anchors, and (3) carbon strips. Each method has its own advantages and disadvantages and not all methods can be used in every situation. An SSC structural engineer can typically determine the most appropriate remediation method based on a visual observation of the failed wall.
Foundation remediation systems should only be installed only by experienced foundation repair contractors who have been certified by the manufacturer of the system used.