What is Concrete Waterproofing?

Concrete waterproofing comes in many forms including liquid, sheets, cementitious and bentonite systems. Each has unique benefits, but liquid is the most widely used. Applying a concrete waterproofing material concrete prevents water from seeping into the concrete. Water can erode concrete over time and require expensive repairs to fix. Concrete waterproofing is required in many areas on any new concrete basement wall or structure in order to pass inspection and to meet the required building code.

The most common cement waterproofing is the liquid type. This product is a thick substance that turns into a rubbery coating once applied to the outside of a concrete wall where the dirt will make contact with it. In order to properly apply this type of waterproofing, the cement must be cured and clean. The liquid is mopped or rolled onto the cement and is allowed to cure or dry. This is popular when building a basement wall or any concrete which will be covered with earth. Once dried and the substance has reached a rubbery texture, the dirt is filled in around the wall.

Liquid sheet concrete waterproofing is composed of large square sheets of a very sticky rubber-like material. The sheets are placed against the concrete wall where the dirt will be pushed around it. Once placed, the sheets are impossible to remove. This type of concrete waterproofing is not as effective as the liquid type due to the seams between the sheets. Sheets are also higher in cost than the liquid. The sheets do provide a more uniform covering that remains a constant thickness when applied.

Cementitious waterproofing is applied to concrete much like a layer of mortar. The waterproofing is mixed and applied to the concrete in a thick uniform layer. This product dries and becomes a hard as the concrete itself. The disadvantage to this type of concrete waterproofing is that is does not flex or stretch with the concrete and is prone to cracking. This, however, is the most user-friendly product.

Bentonite types of concrete waterproofing come in sheets of a cardboard-like substance. The concrete waterproofing material, a clay-like substance, is sandwiched inside of the sheets. These sheets are attached to the concrete and the earth is moved against the concrete wall. The water enters the cardboard material and causes the clay to swell to many times its original size. This type of waterproofing is not as popular as other forms since it takes water to activate and its coverage cannot be seen until it is covered with earth and water has entered the material.