Travertine is a form of marble tile that has pockmarks and holes running over the flat surface, the result of natural mineralization of the rock. The holes are part of the character of travertine, but they're also a problem when it comes to dirt and moisture, which can collect there. One approach to travertine is to fill the holes with grout, so the patterns of the holes are still visible but won't collect dirt. Make sure the grout you choose is darker than the travertine so the patterns stand out.
Instructions
1. Use a level and pencil to mark a horizontal line along the base of the wall, up from the floor by the height of a travertine tile plus 1/4 inch.
2. Measure and mark the middle of the horizontal line. Use a level and pencil to draw a vertical line up the wall, from top to bottom, at the middle.
3. Apply thinset mortar over the bottom of the wall, along the length, from the floor up to the horizontal line.
4. Hang the bottom course of travertine tiles under the horizontal line, starting at the center line, pressing them to the wall on both sides of the vertical line. Work your way out in both directions toward the walls. Set spacers between the tiles as you hang them. Use a wet saw to cut the end tiles as needed.
5. Install the tiles for the next course up in the same way, starting at the middle and working to the sides. Repeat, tiling course by course up the whole wall, with spacers between all the tiles. Cut the end pieces as needed.
6. Let the tiles set over night. Pull out the spacers.
7. Coat the travertine surface with tile sealant, using a paint brush. Seal only the flat parts of the tiles (not the holes or spaces between the tiles). Let it set for six hours.
8. Grout the wall beginning at the top, spreading the grout downward over the whole surface, using a grout float. Scrape the long side of the float over the face of the travertine to force the grout into the spaces and holes, while pulling it off the flat parts. Wipe up the excess grout from the surface with a damp sponge, leaving it in the holes and spaces.
9. Let the grout dry for four or five days. Brush on second layer of tile sealant, covering the grout and tile.
