Back buttering tile is a highly opinionated and widely-debated topic among tile installers. Although it’s recommended for natural stone tile, it’s not always necessary or required to get adequate mortar coverage on ceramic and porcelain tile.Click to see full answer. In this manner, what are the arrows on the back of tile for?According to our tile experts the arrows on the back of the tile indicate directionality. In other words the arrows are there to assure all of the tiles are laid out facing the same direction. This is to assure the pattern of the floor is uniform.Beside above, do you need to back butter mosaic tile? This back-buttering step is best used for all glass mosaic tile, but is essential when using fully transparent tile, in order to keep any remaining trowel lines on the substrate from showing through. Back-buttering also insures near-complete (95%) surface adhesion between tile and substrate. Keeping this in consideration, should you back butter subway tile? Back-Buttering shouldn’t be needed. But, the best determination is to set a tile & then pry it off. You should have a nice even smush of Thin-set that covers the whole back of the tile. If you don’t get full coverage, then you can try it again with a bigger notch trowelon a fresh clean tile.What do the numbers on the back of tile mean?When doing projects in your home with ceramic tiles, it’s important to be able to identify the tiles. At the back of each tile is a lot number that indicates the batch. When shipped to stores, ceramic tiles are also contained in boxes that have the lot number and the manufacturer’s name.