Lessons in leakage -- efflorescence

How can water leak through solid concrete?

This Home has efflorescence.

Water leaking into your basement doesn’t mean there’s something wrong with your foundation. Consider the following facts: Concrete is a very porous material. Moisture from the soil is easily absorbed by poured concrete or concrete blocks, even when the exterior of the foundation has been coated with a damp-proofing compound. When the concrete becomes so saturated that it can’t hold any more water, seepage into the basement begins. Evidence of this seepage often takes the form of efflorescence –white powdery stains on concrete walls deposited by seeping water (see photo). Water pressure (aka hydrostatic pressure) exerts tremendous force. A cubic foot of water weighs more than 60lbs. In wet weather, there can be thousands of cubic feet of water pushing against foundation walls and up against a basement’s concrete slab floor. When you have so much pressure, even tiny cracks and gaps can admit a great deal of water. This explains why a great deal of leakage occurs along the crack between the basement floor and the foundation wall.