Typically after a basement is poured, the soil that was removed in order to pour the foundation is backfilled into the remaining space flush to its walls. When this is done improperly, the differences between the backfill soil and the original soil on the property can cause cracks to the foundation during the settling process.

Over time, water will build up around the foundation. The weight of the accumulated water presses on the foundation walls, creating hydrostatic pressure.  The hydrostatic pressure on the foundation wall will cause it to crack or leak.

In most cases, due to gravity, the majority of the hydrostatic pressure occurs on one side of the foundation, and only a partial foundation replacement is needed.

Extremes in the weather can cause swelling and shrinking in the concrete, as well as the surrounding soil, and eventually the concrete can crack.