QUESTIONWhy Grout Joints? - Hi,
Can You please tell me if the travertine tile should be set with a grout joint or no grout. I am have this installed in my home tomorrow and the installer is telling me he needs to utilize a small grout joint to lay the tile and tight is not possible. I was under the impression the natural stone should not have any grout between the tiles. I would appreciate any information you could give me.
ANSWERANSWER - All stone or ceramic tile installations should have a grout joint for two basic reasons. First reason is that tiles will vary in size to some degree and the grout joint allows the installer to compensate for those irregularities to some degree to allow for a straight grout line. The more the variation in size the wider the grout joint should be for the tile. That is why Mexican paver tiles have such large grout joints is because they tend to vary in size so much.
Second reason is that tiles will expand and contract to some degree due to thermo conditions, moisture conditions and various dynamic movements within the structure. The cement grout joint is much more compressible than the tile itself. If the tiles are butt up to each other then expansion within the floor can lead to spalling at the edges of the tile. It is normally recommended to not have a grout joint any more narrow than 1/8” so it can be fully filled with grout and be more stable. The stone industry standards do allow for a grout joint as narrow as 1/16” wide if the stone tile is especially precision cut.
Also consider that the smaller the grout joint width the more likely you will get lippage from two adjacent edges of tile, where one edge is higher or lower than the other. The industry standard for smaller width grout joints is that there can be no greater lippage than 1/32”.