Tile Repair Mortars

Suitable Mortars

• If a commercial mortar mix or ready-to-use mortar is being selected, choose a mortar that is labeled for tile repairs. Most mortar mixes labeled for tile or masonry repair are polymer-modified, containing admixtures that allow better bonding between the mortar and adjacent surfaces. Repair mortars are often sold already prepared in plastic tubs and may require only the addition of a small amount of water or admixture. In other cases, the mortar mix may be sold dry and water or another liquid additive must be stirred into the solids to create a workable substance.

Mortar Additives

• In some cases, you can modify standard or thinset mortar, although this method, because of the amount of modified mortar typically produced, may be practical only for large-scale repairs. Possible additives could include bond enhancers, which usually contain latex emulsions or fine polymer fibers to control shrinkage. Additionally, if repairs are being made in an especially cold or warm environment, the inclusion of accelerators or retarders may prove beneficial.

Performing the Repair

• Proper placement of damaged tiles and mortar use requires removing damaged tile and grout and enough mortar from the underlying bed to allow space for new mortar. Remove the old tile and scrape or chisel out the old mortar or mastic to a depth that will allow the replacement tile to be level with adjacent tiles. Clean the area of debris or dust that could affect the bonding ability of the mortar. Apply mortar to the back of the tile with a notched trowel and place the tile in its space. Use gentle taps with a mallet to set it evenly and check for level. Clean away excess mortar and let it sit for at least a day before applying grout.

Additional Repair Materials

• Grout provides an important finishing touch to a tiled area, filling the gaps between tiles. Grouts are generally either epoxy or cement-based. Cement-based grouts can be Portland cement-based, which requires that tiles be soaked in water before application and the grout is damp-cured; dry-set grout contains additives to eliminate the need to soak tiles. Epoxy grout is typically the most expensive type of grout but offers a high degree of chemical resistance, impact resistance and bond strength. Choose a grout color that will best match existing grout. The final step in tile installation or repair is the application of a protective liquid tile and grout sealer.