Wood-like planks and other large format tile
There are some frustrating things about porcelain wood planks that your tile contractor may not have told you… and the salesperson at the store may not know. Here are some tips that you may be interested in before you shop for your wood grain tiles.
They’re not flat
They might look flat at first glance, but if you look closely, they probably aren’t. The center is higher, in other words, they are crowned in the middle. Some brands and types are worse than others. This becomes more of a problem when you offset (overlap) them, which brings us to the next issue:
Don’t do a full offset with wood plank tile
By doing a 50% offset, where the middle of a tile is exactly in line with the grout joint of the next row, you have maximized the amount of unevenness, or lippage, between the tiles. In fact, unless the tile manufacturers say otherwise, the American National Standards Specifications for the Installation of Ceramic Tile sets the limit at 33% maximum offset (ANSI A108.02 Section 4.3.8). This means that on a 24 inch long tile the maximum offset is 8″.
The floor has to be extraordinarily flat
If your floor isn’t flat this will accentuate the problems with the crown of the tiles as you can see in the image on the left. For large format tile, which is any tile with at least one edge longer that 15 in., the maximum allowable variation is 1/8″ in 10ft. Floors are just not that flat nowadays.
Use the correct thinset
With large format tiles you want to use a medium bed mortar and the correct trowel. While I prefer Laticrete 4xlt for this, you may find Marble and Granite mix from Custom Building Products more readily available. With these types of mortars a 1/2″x 1/2″ notch trowel would be the smallest size that you will want to try. Yes, this uses more thinset and, yes, these types of mortars are more expensive, but this isn’t the time to skimp. If you want plank floors, you’ll want to use a medium bed tile adhesive.
Porcelain plank floors can look good but the biggest problems with them can be avoided by simply knowing what to watch out for and planning accordingly. You’ll find that they should last a lot longer than their wood counterparts as well.