Why is it essential to use a moisture barrier under a concrete slab?

Using a moisture barrier under a concrete slab is vital because it effectively prevents moisture from the ground from penetrating into the slab. This is important for several reasons. First, excess moisture can lead to various problems, such as efflorescence, which is the white powdery substance that forms on the surface due to the migration of soluble salts. This can negatively impact the appearance and integrity of the concrete.

Additionally, moisture can also induce cracking and weaken the concrete over time, compromising its durability and the structure it supports. Furthermore, high moisture levels can lead to issues with flooring materials applied over the concrete, such as warping or mold growth, which can cause further damage.

In short, a moisture barrier helps maintain the longevity and performance of the concrete slab while protecting it from potential damage caused by ground moisture.