What is ceramic tile caliber?

I have 15 boxes of 17 inch ceramic tiles sitting in my garage waiting for installation (see post below http://https://terrylove.com/forums/showthread.php?t=21310). These were ordered (as opposed to getting them from available stock) so that they would all come from the same dye lot. The control numbers on all the cases are identical, so I assume this means that they are indeed from the same dye lot. However, 14 of the 15 boxes have a "caliber" number of 5, while one of the boxes has a caliber of 4.

I need to know if this is an issue, and if I should be pressing the supplier regarding this? A Google search doesn't turn up much, except that it has something to do with size. I assume that this is in reference to width, not thickness. If this is true, then those tiles could probably be used along edges where they will be cut to fit anyway?

Comments are appreciated.

A rectified tile is one held to tight tolerances in size...not sure about caliber. You might want to ask this question at the Tile Your World DIY'er site www.johnbridge.com.

Caliber is the facial dimension of the tile, so the size of the tile in the one box is different. Ideally, all of the tile should have the same lot (color) and caliber (size) number.

As you've already figured out, lot is the important number as your job will require that some tile be cut down from two sides. Just set that box aside and mark them so you don't inadvertently set one of them in the field.

Thanks Sam. I did take Jim's advice and posted to the John Bridge forum. Everyone seems to be in agreement. I think I understand. From what I've read, it sounds like a one number difference in caliber will be very minimal, and shouldn't be a big deal if I use them as you describe.

This is very interesting. I googled tile caliber and got the explanation as given. Apparently, due to production variations, there will be slight differences. The manufacturers sort the tiles and assign the caliber number, allowing an installer to select all boxes with the same caliber. This will result in very uniform grout joints.


I have done some bit of tile over the years, and did not know about this number. I knew about dye lots, especially important with some colorful tiles. I think I will go to the store and see if they actually have a caliber number on the box!

I first learned of it the hard way while tiling our kitchen. We had purchased the tile from a salvage yard. The lot numbers were the same but the caliber numbers weren't. I was laying the tile in a straight pattern and didn't have many cuts. I don't recall how far apart the numbers were, but the dimensions were different enough that it would have been very noticeable had I laid them.

Just another case of "it's easy if you don't know what your doing".