Why Is Your Basement Flooding?

There are two important factors that contribute to basement leaking: the clay bowl effect and hydrostatic pressure. Both have similar damaging effects, which is why it's important to be aware of the proper way to waterproof your foundation.

The "Clay Bowl" and your Foundation:

Imagine your home as it was being built. The contractors begin by digging a hole in the ground to make room for your basement and foundation. To do so, the contractor must dig a hole that is a little larger than the space your home will need. The foundation will be built inside this space, and the concrete floor will be poured.

Once the foundation has been built, some of the excavated soil is used to fill in the gap around the outer edge of your foundation.

This soil, known as "backfill", will be loose and fluffed from the excavation. Meanwhile, the untouched soil around it, known as "virgin soil", may have been settling for hundreds, even thousands of years.

What does this mean for you? The backfilled soil surrounding your foundation will always be looser and more absorbent of water than the dense, hard-packed soil around it.

This forms a sort of "clay bowl" around your house -- one that creates an artificial water table around your home. Water collects the most right around your foundation -- exactly where you don't want it to be.

Hydrostatic Pressure and Wet Soils:

Water is heavy! As the soil around your home becomes soaked with moisture, the soil will expand, and the weight of the water will press on your foundation. This is known as hydrostatic pressure.

As hydrostatic pressure builds against your foundation, water will work its way in through any way possible.

Water can make its way through concrete cracks in the walls or floors, through openings around pipes, through basement windows, or even directly through the porous concrete. If you have block walls, water may pass through the block and begin to fill the open cavities.

However, the most common way that water enters a home is through the foundation wall-floor joint. We find that most flooded basements start with a leak here.