Question: What About Tile Mastic? Your Questions Answered
Lots of DIY home remodelers have basic questions about tile mastic, how it is used, and how it relates to thinset mortar. Let's answer some of those burning questions.
Q: What is tile mastic?
Tile mastic is a substance that adheres tiles to walls and floors.
Q: Can tile mastic be used in wet applications?
Not necessarily. The debate rages about this issue. Tile mastic is not known for its high resistance to moisture. Some tilers claim that tile mastic is fine in wet areas, as long as the grout is properly sealed--and kept sealed. Other tilers say that tile mastic should be kept in dry areas.
AcrylPro tile mastic's instructions say that the product can be used in "Interior wet areas with intermittent water exposure such as, tub surrounds and shower walls." The word "intermittent" is important. In other words, it is not for shower floor pans or tubs.
Q: What is the difference between tile mastic and thinset mortar?
Chiefly in terms of composition. Thinset is a mortar, a natural but inorganic substance made of portland cement, silica sand and moisture retaining agents. In fact, you can even buy sanded or non-sanded thinset mortar. Tile mastic is a polymer-based adhesive.
Q: Does it give off an odor?
Yes, it usually does have an odor. Thinset mortar has little odor.
Q: What is the difference between tile mastic and thinset mortar in terms of installation and procedure?
Tile mastic will have better adhesion properties for vertical surfaces. It has great "grab," and this is important on those walls. Another difference: sometimes when tiling you need to build up depressions a bit with your thinset mortar. This is impossible to do with the tile mastic because it is more syrupy and has no building capabilities.