The Clay Bowl Effect and Hydrostatic Pressure

Once your home’s foundation was completed, previously excavated dirt is replaced or backfilled around the walls. This “fluffed up” soil is loose, more aerated, and not as dense or tightly packed as undisturbed soil farther away from the house. This looser soil tends to absorb water easier than compacted soil. So, when water collects in the soil immediately surrounding the home it creates a “clay bowl.” The saturated soil expands and puts pressure, known as hydrostatic pressure, on the foundation walls. When this constant pressure becomes more than the walls can bear, they will begin to show signs of failure in the form of cracks and inward movement.