The added cost of floor prep for large format tile.
I was at the tile store the other day and I was looking around at all the happy faces doing their tile shopping. I'm sure some are shopping for a back splash, others maybe for a bathroom remodel. I was left to wonder a very common question in my mind, "Who's installing all this tile!?"
While I was there I noticed many people looking at 6" x 36" plank tile (large format tile). Wow, the stuff looks great and you can tell the excitement in their eyes about possibly having that tile in their home. My main question to myself was:
"Has anyone talked to these people about the added cost of floor preparation for large format tile???"
There's added cost for big tile you ask?... The long and short of this is YES! The Tile Council of North America handbook states that....
"For tiles with at least one edge 15" in length or longer, a maximum allowable variation of 1/8" in 10' from the required plane, with no more than 1/16" variation in 24" when measured from the high point in the surface" (Page 31 TCNA Manual 2016)
So what this means is you cannot have a wavy floor and install a big tile! As the tile size increases, the effect of the floor irregularities is compounded. If there is a bump or dive in the floor it will make it impossible to install large tile. You will have lips and poor coverage and support under the tile.
I have found that very few homes have wood or concrete substrates that are ready out of the box for large tile. EVERY floor needs some degree of prep.
Prep, is short for "preparation". Meaning, flattening or leveling the floor to get it ready for whatever material you're hoping to install.
When we show up to a large area where we know large format tile will be set, what we'll do is take out a large straight edge, 8'+. We set it on the floor and decide what kind of prep will need to be done. Many times if there is flooring already down you won't know what needs to be done until the old flooring is up. This adds a bit of a mystery to the installation process and you need to make sure your builder gives you an allowance or find out if the unexpected labor is in his/her price. Many tile people won't tell you about the added costs until the tear out is done, and hit you with the extra cost! This is why I'm writing this post!
If you do indeed have a wavy floor there are a couple ways to fix the problem...You can self level the area, which will raise the level of the floor by as much as a quarter inch (think transitions between rooms) or you can use a product like Feather Finish by Ardex to fill the low spots, or you can grind the high spots. Or you may have to do a combination of all those things! The repair of the floor is where it is SO important to have a skilled, experienced tile installer. As I always say, the quality of the finished tile job is determined before any tile is ever set! Below is an example of our work where we used Lev-Tec leveling system to help get the flat floor:
With large tile the quality of the tile is very important as well. Every tile has a certain amount of warp to it and if you're looking for a flat, smooth floor you will want to cite the manufacturer for grout size and layout specifications. Many people want a 1/16" grout joint with a brick set...but on most occasions, the manufacturer of the tile will recommend NOT to install the tile in that manner. So, ultimately it's really not up to us or you, for that matter, how your tile is set. The layout and grout joint size is determined by the manufacturer and is backed up by the TCNA. A 50 % offset with a 1/16" grout joint will accentuate the warpage in the tile. The Tile Council of North America says:
"The actual grout joint size shall be at least three times the actual variation of facial dimensions of the tile supplied. Example: for tile having a total variation of 1/16" in facial dimensions, a minimum 3/16" grout joint shall be used." (Page 38 TCNA Manual 2016)
ANSI standard 108.02 also covers grout joint size, lippage and brick set. Read it all here for yourself:
https://www.ceramictilefoundation.org/blog/ansi-standards-tile-installers-best-friend
Would you consider it important to have your project installed according to national standards? If so be sure to hire a contractor that uses the "Handbook Method" (Like us)
Most tile has a great deal of variation. You CAN find consistent tile....but be prepared to pay a high dollar, if you want a flat, consistent floor. It can cost big bucks not only when buying high quality, A+ grade tile....but also for installation. Most interior designers and sales people do not have and interest in telling you what to expect in this regard. Their main priority is to sell tile and design services. Sales people often time promise the world but the material they are selling has too much variation to allow the installer to deliver on said promises.
Another thing to think about is that Larger tile involves larger tools! A more expensive score and snap…a much bigger tile saw. Getting “full coverage” under your tile is also much more difficult. Larger tile is also harder on the installer’s body!
When you're shopping for tile, know that bigger tile comes at a greater cost! Self Leveler is upwards of $30 a bag plus the labor and time of installation! For evidence regarding the consequences of not preparing a floor properly and not following guidelines for large tile, go to ANY COMMERCIAL SPACE that has large format tile and look around. You will see lips and dives everywhere. Here's an example and this is not our work:
A couple things to notice when hiring someone to tile a floor:
1. Does the installer check the flatness of the floor with a large straight edge?
2. Does the installer mention the extra cost involved in installing big tile, Like the possibility of extra floor prep?
3. Does the installer use some sort of leveling system to help get a flat floor.
4. Does the installer speak to you about grout joint size, tile offset and the fact that all tile has warpage?
5. Does the installer speak about complete thin set coverage, back buttering tile, expansion joints and crack suppression?
My top piece of advice for you is to have your installer go to the tile store with you to help you shop for tile. They’re going to know what to look for as far as tile quality is concerned and won’t be motivated by making the sale. If the tile you’re ordering is special order, they also may have some knowledge on which manufacturer is the best to buy from. Also, I wouldn’t be surprised when you get the special order tile, if you’re installer decides to send it back. We’ve had to do it before. That’s how you know you have a good installer .That’s a person who isn’t just going to throw something on the wall that’s mediocre quality.
Also, involve your installer in the design process. It’s almost a sure thing that you will get quite a few gems from a person who works with tile every day, for a living.
With that said, if you still decide you want large format tile be prepared for the extra cost of doing it correctly (following TCNA and ANSI standards) and I hope you are now armed with knowledge to help you avoid a construction nightmare, which have unfortunately become typical in this industry.