The ANSI standards provide excellent guidance in the proper installation of ceramic and porcelain tile. When these standards are followed the installation looks good, but if they are not followed the opposite may be true.
As you view the attached photo of a fireplace hearth, you probably have one of two opinions: it either looks really good, or possibly really bad. But there is actually a third possibility: it may be a matter of opinion.
The ANSI standard A108.03-4.3.1 states, “Center and balance areas of tile, if possible.” This is pretty straightforward. The cuts on the left should be the same size as the cuts on the right. And of course, there may be exceptions to the rule, especially when a multi-room layout doesn’t allow this rule to be followed.
The ANSI standard, A108.02-4.3.2 makes this statement: “An excessive amount of cuts shall not be made. Usually, no cuts smaller than half size should be made. Make all cuts on the outer edges of the field.” The fuzzy part of this first sentence is in defining how we understand the word “excessive.” This could mean no more than two cuts—or it could mean less than 10. No matter how you look at it, the decision is really subjective.
But the second sentence clearly says that none of the cuts should be less than half a tile. The cuts in the photo are significantly smaller than one half of a tile. Two, one-half inch slivers compared to a 12x12 tile are not even close. The last sentence is also clear when it says that the cuts should be along the edges of the installation. Again, this rule has been compromised.
Let’s recap what we see. The cuts are centered and balanced (done correctly). There is not an excessive number of cuts (only two), but the cuts are less than one half tile (not done correctly). Additionally, the cuts are in the center of the layout, not the outside edges (not done correctly).
So is this installation following the applicable ANSI standards, and does it look acceptable? Quite honestly, the choice is yours—or better yet, review the possibilities with your customer for his or her decision before beginning your work.
Oh, one final note. No matter which choice you made above, the job is a failure. Notice that one-third of the installed tiles are broken. Lack of mortar coverage is the culprit.