What is Grout? Now this is an interesting question. The most intriguing aspect of the question is the sheer number of different impressions we have heard homeowners offer when trying to describe it. For example,
- “the dirty stuff on the shower wall”
- “the material coming up from our tile floors”
- “what we have to scrub all the time”
- “the cement between the tiles”
- “gritty stuff on the floors”
Well, we guess you get the idea. Now let’s talk about what grout really is and rest assured that it can be your friend. The Ceramic Tile Institute of America says that colored grout, what you are most likely to encounter, is “commercially prepared grout consisting of carefully graded aggregate, Portland cement, water dispersing agents, plasticizers and color fast pigments”. So, for the layman, what is important in that definition is the combination of cement, water, and colorant.
What are the basic types of grout?
- unsanded grout is typically used when grout joints are 1/8” wide or less.
- sanded grout is the norm with grout joints greater than 1/8” wide.
- epoxy grouts will be found in more challenging installations such as when acids or oils are anticipated.
The joint, as referenced above, is the space between the tiles or stones. Please keep in mind these are only the basic types of grout.
There are a few more things to know. We have been asked on many occasions, “why is grout used”? There are three prominent reasons:
- Ceramic tile and terra-cotta tile are two examples of materials that are fired in a kiln. Think of a kiln as an “industrial oven” of sorts. Continuing that analogy, imagine the tiles are similar to cookies in your oven. The size and shape that go in are not exactly what comes out. So, grout is what fills the open spaces, or joints, that are needed to align the imperfectly shaped tile. Please see image above from our Reclaimed Terracotta Collection.
- The grout also serves to bond, or adhere, the tiles more precisely in the overall floor or wall assembly. You know that your tile is installed in mortar or mastic on the back or down side. The grout enhances the strength by further bonding side to side.
- There are situations where the grout and the grout joint add to to slip-resistance. A classic example is a shower floor composed of 1” x 1” or 2” x 2” mosaic tile where this cementitious material every inch or two inches provides a lot of “grab”.
To help further answer What is Grout?….it is wise to talk about color. The oldest solution is the gray joint color in the terracotta floor immediately above. Another approach is to blend the grout with the color value of the tile. This is clearly illustrated by our Marsala Classic Tile in the middle of the post. This is probably safest and easiest.
Lastly, is to contrast the color of the joint and the field tile. This idea may have a downside given that grout is usually “smeared” over the face of the tile in the process of working the grout into the joints. Consider what a black grout might look like if left too long on the face of your awesome white ceramic tile.
We hope this post has done a reasonable job of answering the What is Grout? query. Thanks very much for reading!