Types of Waterproof Subflooring

Waterproof subflooring in bathrooms, kitchens and entryways repels water before it can damage the subfloor. It can also prevent the growth of mold and other allergens, improve the surface appearance of the floor and aid in its structural stability. There are many types of subflooring, both natural and synthetic, from costly to affordable.

Waterproof Sheet Membranes

Self-adhering rubberized asphalt membranes are the most common form of waterproof subflooring. It is effective when installed correctly, and even when it is not, the system can be fixed with ease. The product's consistency is the main advantage. Manufactured to meet rigorous conditions, the thin sheeting is dependable and the product's bituminous base makes its lifespan unparalleled. Drawbacks of this type of subflooring includes cost for both the product and the labor to install, and the seams that occur when overlapping the sheeted material.

Liquid Membrane

Applied via spray, roller or trowel, this type of waterproof subflooring is a quick and cheap waterproofing element. It is important to follow the manufacturer's guidelines for installation because the product can be inconsistent, which can result in a flawed waterproofing membrane, compromising the project.

Water-Based or Silicone Sealer

One-part water based silicone sealants are ideally suited for the do-it yourself market. Used with tile, they provide a permanent seal against water, moisture and air. The sealer can be caulked on, and if any errors occur, can be easily cleaned up with water. The products have no odor and are typically environmentally friendly.

Natural Membranes

Sodium bentonite, a clay material, is a nontraditional waterproofing system that typically comes in panels that can be installed easily as subflooring. The environmentally safe panels soak up any and all water, expanding the product to 15 times its original volume, effectively sealing the subfloor. However, some contractors are wary because of the inability to effectively check the seal before covering it up.

About the Author

William Vogel specializes in new art, old architecture and contemporary music. Originally from Chicago, he earned a B.A. in art history from Denison University in Granville, Ohio, as well as an M.S. in historic preservation from the Pratt Institute in Brooklyn, N.Y.