by Dan Marvin
The newest innovation in tile is thin units that marry reduced thickness with large size. Whereas traditional thickness tiles are 9 mm (3⁄8 in.) or thicker, these new-generation thin tiles are 3 to 6 mm (1⁄8 to 1⁄4 in.) thick, and can come in dimensions up to 1 x 3 m (3 x 10 ft). This is not a typo—one thin tile panel can cover 3 m2 (30 sf) or more.
While thin tile provides an exciting array of design possibilities, it also poses potential challenges for installers and general contractors. This article outlines the important considerations for specifying this new product technology.
As background, it is important to know tile continues to build in popularity as a surface covering for floors and walls, both residentially and commercially. The trend for tile continues to be larger sizes and less grout joints. Traditional large-format tiles are heavy due to their thickness, which makes them expensive to transport. Heavier tiles also require more energy (usually natural gas) to fire them to the 0.5 percent porosity or less required to be considered porcelain.
In the early 2000s, Italian tile-equipment manufacturers began exploring the potential for producing large, thin tile. Decreasing the mass of tile by making it thinner would solve both these issues, allowing the tile to be transported less expensively and require less energy to manufacture.
While the tiles were getting thinner, they were also getting larger. Traditional units are constrained by the size of the steel molds used to press them. As thin tiles are usually pressed on a belt, they are constrained only by the width of it and the handling equipment. This led to wider and longer formats. Thin tiles can be cut efficiently using a ‘score and snap’ system that allows for easy production of various sizes from one sheet. The thinnest tiles are also somewhat flexible and have reinforcing mesh adhered to the back to allow for installation in areas like curved walls where traditional tiles would be too rigid.
The processes were developed in Europe and started finding distribution in the United States around 2010. Since then, there have been various efforts launched to develop standards, optimize installation, and educate design/construction professionals (and the tile-buying public) on the product’s strengths and weaknesses.
The current state of large tiles
The challenge is the lack of product and installation standards. American National Standards Institute (ANSI) A137.1, American National Standard Specifications for Ceramic Tile, currently covers traditional size and thickness tiles, but does not address mesh-backed tiles, flexible tiles, or extremely large formats. Likewise, ANSI A108, American National Standard for Installation of Ceramic Tile, does not adequately address tiles that may be as tall as the room.
To fill this void, most importers offer classes on how to handle and install the product. Classes are also offered by installation product providers, and an advanced certification of tile installers is being developed by six industry groups:
- Ceramic Tile Education Foundation (CTEF);
- International Masonry Institute (IMI);
- International Union of Bricklayers and Allied Craftworkers (IUBAC);
- National Tile Contractors Association (NTCA);
- Tile Contractors’ Association of America (TCAA); and
- Tile Council of North America (TCNA).
Additional support is available through technical guides, videos, and trade show demonstrations.
The main functional drawback to thin tile is that there is no longer a margin of error in installation or service environment for which the tile’s strength can compensate. Applications such as rolling loads (e.g. suitcase wheels) and point loads (e.g. chair legs or ladders) can quickly overcome a thin tile installation if the tile is not well supported and installed with minimal lippage.
Based on early results, the U.S. tile industry has published a statement suggesting only products 5.5 mm (1⁄4 in.) or thicker should be used for floors. This runs contrary to the recommendations of some individual producers that allow thickness of 3.5 mm (1⁄8 in.) with a mesh backing to be used for horizontal applications.
While standards efforts are underway both at the U.S. (i.e. ANSI) and global (i.e. International Organization for Standardization [ISO]) levels, the current answer is to follow the best practices developed for handling and installation of these products. Although not every manufacturer of tile and setting materials endorses all these recommendations, this article provides a general list of thin tile considerations and some best practices for addressing them.