What Is a Backer Board?

Do you have a tile project in the works? Then do you want to know the secret behind any successful tiling job?

It’s the backer board.

Whenever we walk into a gorgeous bathroom or kitchen, we only appreciate what we see, which is the tile design or quality. But beneath the tiles are backer boards. These are the substrate material for tile that ensures that the tile surface is level and consistent.

Also, the best backer boards will make any tile installation more stable and enduring, so that you can enjoy your tile project for many, many years.

Because they work quietly in the background, backer boards don’t get the respect that they deserve. But we’re here to change all that! Keep reading to learn more about this construction material that will serve a crucial role on your next tile project.

What Is a Backer Board?

A backer board is also known as a cement backer board or cementitious backer unit (CBU). It’s a prefabricated sheet, usually ¼ to ½-inch thick.

It’s made of cement-based materials, including cement, silica, water, and limestone flour. Fibers (Kevlar, cellulose, or fiberglass) are also added to enhance material strength.

You can think of it as the equivalent of drywall, another undervalued construction material. However, instead of supporting walls and ceilings, a backer board does it for tiles.

Benefits of Backer Board Installation

Why use a backer board as a base for tiling? Why not go with plywood and other wooden substrates?

To understand the value of cement backer board installation, think of the areas in your house where you see tiles. We typically use tiles in kitchens, bathrooms, and laundry rooms, the so-called “wet areas.” These spaces are moisture-rich, which can cause a lot of problems if you use an organic base.

Here are some compelling reasons to use backer boards.

No Organic Material

Wood-based substrates, such as plywood and drywall, contain organic material that can rot or shrink when exposed to water. Also, they promote the growth of mold, which can pose a serious health risk.

A cement backer board lacks organic material that can be susceptible to the problems mentioned.

Prefabricated

Cement backer boards are manufactured and dried in a factory. It’s also where they’re cut into standardized sizes.

Backer board installation is more efficient compared to using a mortar bed, the tile backer used traditionally. With dry-pack mortar, you still have to mix cement, sand, and water and wait for it to dry. That’s why even experienced tile setters prefer to use backer boards when they can.

Stronger and More Stable

A backer board is porous, which means that grout, thin set, and other tile adhesive stick well to it. Due to the lack of organic material, it’s not prone to shrinkage. All these factors contribute to the stability and consistency of your tile installation.

Furthermore, backer boards usually contain strengthening additives, like the reinforcing fibers mentioned earlier.

Backer Boards Are the Foundation Your Tiles Deserve

When embarking on a tile project, there’s no question that a backer board is your best option to use as a substrate. They work hard behind the scenes to provide strength, stability, and durability to your tile surfaces.