Preventing scratches in glass tile with MAPEI grouts

Suitable glass tiles are those that meet the ANSI A137.2 specification. Some glass tiles are more decorative, where the end goal is not necessarily strength. Some other glass tiles are rated more durable and may be stronger by design. The hardness of a glass tile cannot be determined by visual inspection.

Glass tiles are known for their relatively low scratch resistance and higher thermal expansion, which is the change in size of an object due to temperature changes. Believe it or not, glass can expand more than ceramic tile! Customers are surprised when they hear this; the assumption is that glass does not expand at all.

Glass tiles are classified into two categories: standard and natural. Standard tiles are manufactured to meet specific sizing tolerances, ensuring uniformity in size. In contrast, natural glass tiles are produced with inherent variation and not held to specific sizing tolerances. Additionally, natural glass tile is not associated with any sustainability criteria.

MAPEI grouts and glass tiles

Grouts such as MAPEI’s Ultracolor Plus FA can be used as a glass tile grout; however, it is recommended to test the grout first to confirm compatibility with the glass surface.

Regarding Ultracolor Plus FA, the “FA” in the product stands for “fine aggregate” (or, sand). This size of sand is finer and much powderier when compared to conventional sanded grout, which has a much coarser grain. The finer the sand, the less likely that the sand will scratch softer surfaces.

In most installations, Ultracolor Plus FA can be used successfully with glass tile. It is important to note, though, that a new straight-edge grout float should be used when applying the grout. Scratching can result from using old floats with caked-on mortar or grout on them, and not necessarily from the grout itself.

Because it is impossible to determine if a glass tile will scratch when using standard glass tile grout, it is always recommended to do a small mockup and check before completing the installation. If you experience scratching, choose an unsanded grout such as MAPEI’s Keracolor U Unsanded Grout.