Yes, you can always use a large format tile mortar for smaller tiles.
Understanding Tile Mortar Types
When selecting mortar for a tile project, it's crucial to match the mortar type to the tile size and location (floor or wall). While different mortars are formulated for specific applications, there's a flexibility when it comes to using mortar designed for larger tiles on smaller ones.
Why Large Format Mortar Works for Small Tiles
According to industry practices and references, you can always use a large format tile mortar for smaller tiles, but not the other way around. This is because large format tile mortars are typically designed to handle the significant weight and dimensions of larger tiles. They often provide superior bond strength, coverage, and slump resistance necessary to support heavy tiles on both floors and walls without the mortar compressing excessively.
The Risk of Using the Wrong Mortar
The reference highlights the potential issues when using a mortar intended for small tiles on large tiles:
- Squishing Out: Mortar not formulated for large format may be too thin or lack the necessary body to support the weight. This can cause it to squish out from under the edges of the tile during installation, leading to uneven surfaces and weak spots.
- Lack of Support: Insufficient support from the mortar means the tile isn't properly bonded across its entire surface. This is problematic on both floors, where it can lead to cracking underfoot, and walls, where the tile could potentially sag or detach.
The reference also notes the importance of selecting mortar for floor tiles that is non-slump. Non-slump mortar is essential on floors to prevent the weight of the tile from pushing the mortar down or causing the tile to sink into the adhesive bed.
In summary, while mortar is specialized, using a more robust, large format mortar provides sufficient, if not excessive, support and bond for smaller tiles, ensuring a successful installation.
