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"Chicken little - my fill is coming out, my fill is coming out"

" We field many calls here at QDIstone. One of the most common ones is: "We recently had travertine installed in our house, and we've noticed all kinds of little holes showing up in the floor. Did we get a poor quality travertine?"

The answer is "no" you did not get poor travertine or a poor grade of travertine. You simply got "travertine"! There are many varieties of travertine on the market, sourced from many countries. One thing they all have in common is voids within the stone composition as a result of trapped gasses during the forming process. This is the classic characteristic of real travertine. During the production of travertine after the initial quarrying of blocks, these voids can either be filled or left unfilled. Today it is very common to fill them, the filler material is generally cement based, but may be resin based. The more color that is added to the filler the weaker the fill becomes. Therefore, you may see fillers that are very light in color as the common color is white. During the filling process, all voids that "window" through the face of the stone tile are filled, and the filler material is ground to an even surface finish and honed along with the surface of the travertine. Voids that are within the tile and not exposed from the back or the front are called "interior voids". What these customers are seeing is these "interior voids" that were not exposed to filler, coupled with a fragile shell of stone covering it, exposed to a load from walking or rolling over it, breaks exposing a void. Most customers think that the fill is coming out! This is rarely the case. MIA (Marble Institute of America) Design manual 7 documents this behavior of travertine, and clarifies that it is both acceptable and common practice to fill these voids in place as they become visible. Once the floor has been lived with for a year or two, most of the barely subsurface voids will have been exposed. Filling with a non-sanded grout matching as close as possible to the original fill color will bring the floor back to its original intended look. One other critical practice that is commonly over-looked is for the installer to "back-fill" the back of the travertine tile during the installation process, this will aid limiting these break-through voids.