Type of Mortar for Shower Tile

Thin-set mortar provides the bond -- or stick -- between the shower wall and the tile itself. Although you'll be confronted with several thin-set mortar choices in the aisle of a home improvement store, know that each adhesive is simply material-specific. Expert tile setters offer up an important piece of DIY advice: after selecting a thin-set mortar for your project, perform a bond test on a sample piece to see how it sticks to the tile you plan to use. Doing this confirms the quality -- and thus the longevity -- of the shower-to-wall-tile bond.

Basic Thin-Set Mortar

Different types of thin-set mortars are designed for different types of tile.

Basic thin-set mortars cost less than specialized mortars but do not contain special bonding agents. Basic thin-set mortars are specifically engineered to bond only to basic clay-bodied ceramic tile and porous natural stone tiles like slate and travertine.

Modified Thin-Set Mortar

Thin-set mortar manufacturers add special bonding agents to certain thin-set mortars including acrylic glue agents, creating "modified" thin-set mortars. Modified thin-set mortars provide an extra bond to nonporous materials such as porcelain tile, granite tile and composite tiles. Modified thin-set mortars offer an excellent insurance plan for your hard work by protecting against loose or hollow shower tiles. They are available in a liquid form (which must be added to plain thin-set mortar) or ready-mixed in a bag.

Flexible Thin-Set Mortar

Flexible thin-set mortars are polymer-modified and also containing additional anti-crack components. Flexible thin-set mortars are costlier than traditional and modified thin-set mortars, but offer protection against substrate cracking (up to a certain width). They are ideal for existing shower remodels that require setting new tile over rough, cracked, or older substrate surfaces.

Medium and Thick-Bed Mortar

Medium and thick-bed mortars are also polymer-modified, and contain chemicals and components that protect against sagging and settling issues commonly associated with heavy, large-format tiles and natural stone. Choose this mortar if you plan to install thick natural stone tiles that vary in thickness and weight.

About the Author

Residing in San Diego, Calif., Tim Daniel is a professional writer specializing in politics. His work has appeared at both the Daily Caller and Pajamas Media. With more than 20 years of experience in the field of construction, Daniel also specializes in writing about tile, stone and construction management. He is pursuing a bachelor's degree in communications.