Latest Industry Guidelines on Large Format Tile

Discussion in 'Tutorials' started by jadnashua, Aug 18, 2014.

  1. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    FWIW, the 'new' industry term for what used to be called medium bed mortar is now LHT mortar (large and heavy tile). You'll see that in the name on some of the newest formulations of suitable mortar. There was no industry standard defined for medium bed mortar, and larger tile really begged for one - this is it, but it's still in process.

    I was in a class today, and the industry standards on large tile has been an evolving and moving target, but the latest recommendation contains the following points:
    - you should use a non-traditional (at least to the USA) trowel. I don't remember the name of the trowel, but it originated in Europe and has weirdly shaped notches that essentially has an angled, tall slot that falls over with minimal actual visual notching, but it does gauge the thinset well, and provide a nice even coverage I may try to take a picture or find a link for one, and if I do, I'll post it.
    - burn then trowel LHT mortar on the floor
    - burn then trowel LHT mortar on the back of the tile
    - use a floor leveling system (I saw MLT's clips in use today, and like it better than the TLS, but there are others and they all should work as well)
    - use a vibrating sander (no abrasive pad) after setting the tile in place to bed it properly (do not beat it in with a pad and mallet) - this does an amazing job of creating great coverage with no or very minimal gaps in the back of the tile. It is critical to start in the middle of the tile and work outwards, otherwise, you'll potentially get air trapped in the middle that you'll never get out and have a void.
    - run the trowel on both the tile and the floor (or wall) across the shortest dimension of the tile's surface to allow a path for any trapped air to escape rather than be trapped

    Now, over the next year, these recommendations may get further refined, but after seeing it performed today, the results are pretty impressive. After setting and cutting some big tiles, they set a big piece of clear plexiglass, and you could see the thinset moving around, the air coming out until the whole sheet looked quite uniform as there were no longer any visible notches - it just looked like it had been applied flat (note, it's impossible to gauge the amount of thinset if you don't use a notched trowel). Most of these big format tile are fairly flexible, and to get a good result without a wavy surface and to minimize lippage, you really do want to use a leveling system with them AND have a very flat floor.

    If you skimp on the floor prep, expect funky results that will get worse the larger the tile (we played with a 1Mx2.5M tile today -almost 40" by 120", and they make bigger ones - that's a big tile!).
     
    angelo polinario likes this.
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    A bit more...

    Right now, there are only a few floor testing machines in the entire USA that can test one of the biggest of the large format tiles (biggest I've heard of is 5' x 10'), and Mapei has one and donated one to the TCNA (it's about a $150K machine). It's neat in that it can also simulate a growing crack in the substrate.

    Anyway, these large format tile can vary from somewhere in the 3.5 - 6 mm thickness range. To date, none of the 3.5mm (and around that lower limit) tiles have survived the Robinson floor test (or a modified one that can test all edges). All of the tiles have failed by chipping at an edge and analysis showed it was fully supported by the thinset, so it was not an installation error. The thinnest tiles that have survived the floor test are over 5mm thick, so keep this in mind when you are considering where you might like to use one of these.

    It is anticipated to cost in the order of $6K average to buy the tools necessary to move, carry, cut, and install large format tile with minimum risk, so it probably won't be a viable DIY'er option unless you are either very creative or very lucky, or have a place that will rent or loan the required bits. Those big panels are like moving and cutting a large, thin piece of glass, and it's really easy to snap one in half, or crack off a corner unintentionally. If you can plan things well in advance, depending on who you buy them from, the factory can cut them to size for you and they'll be perfectly straight and square (but your application may not be square!).

    Anyway, they're neat, have their application, but are not for everyone, nor should it be expected that everyone can successfully install them. A single tile could cost in excess of $1K, but the prices vary by size, thickness, pattern, and manufacturer. They are NOT easy to transport and if the floor or wall is not VERY flat, it will show since the tile will flex to follow some of the variations. You will NEVER be able to remove a tile to check for coverage (one reason for buttering both the floor and the back of the tile) without it breaking, and you may find it almost impossible to move it once it is laid into the thinset, so careful placement is critical, too. Even if the lay down bond strength is only 5psi, on a 5'x10' panel, that's 18 TONS!

    Making them is a neat feat...whether it is useful is another issue altogether. I'll let you decide. In the meantime, if you see some of those maximum sized panels installed, you can marvel at them.
     
    angelo polinario likes this.
  3. Sponsor

    Sponsor Paid Advertisement

     
    angelo polinario likes this.
  4. eurob

    eurob master tile and stone installer

    Joined:
    Feb 16, 2013
    Occupation:
    master tile and stone installer
    Location:
    Montreal
    What working area is needed for storage and manipulation of the large 5' x 10' porcelain tile sheets ? What are the industry guidelines or recommendations for the working area ?
     
    angelo polinario likes this.
  5. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    The class I went to was a cursory, introduction...we only spent a bit over an hour making some cuts, working with the lifting jig, placing a couple of tile, using the orbital vibrating sander to seat it in the mortar, looking at the trolley used to moving the things, and a suggestion on what you could use for a work table (and the hint that you might want it a bit lower to account for the height of the lifting jig underneath while back buttering the tile.

    Most of those tile require treatment as if you were working with a large, thin, sheet of glass (especially the 3-4mm stuff). A suggestion was that while you may want more than two people on the lifting jig, you really cannot coordinate movement and placement of the tile adequately with more than two on the thing. As noted, with the mortar on the tile and on the surface, with the large size and flexibility of the tile, once you set it in place, you are unlikely to be able to move it more than a very small amount, if at all, nor be able to lift it to check for coverage...you'll break it. So, you need to be very careful and coordinating three or more is nearly impossible. And, with the cost of some of those huge tile panels at over $1K each, not for the feint of heart. Depending on your design, you may not need any smaller sections, so even a small chip can mean a significant loss since you may not be able to use the cutoffs anywhere. Even a 'spare' of one or two could eat your entire profit margin on a smaller job (say a three-piece shower).

    Eventually, I'd expect CTEF, and maybe some other places to offer classes, but unless the manufacturers are willing to donate the materials (they do for some things), it will be expensive to enroll. Mapei covered this at the request of the group from JohnBridge.com that arranged the class at Mapei, and I was able to attend. It was not one of their normal subjects for a workshop, but they made adjustments to the presentation material based on requests from the group.

    I wish I could give you more, but that's about it. You might see if any distributor has some broken or chipped tiles they could give you or offer at a deep discount to practice on, but the tile cutter we used, being about a 14' long beam with suction cup mounts itself is not cheap. The lifting jig is a substantial piece considering it can't twist over its length to allow you to place the tile accurately and with a 10' panel, even though it is aluminum, is somewhat heavy. Then, add the tile with a full coat of mortar on the back, and that's why you might want more than two people to carry the thing, it isn't a good idea!

    This is an evolving process. Until installers can reliably handle and install the panels, there won't be a huge market, and until there's a bigger market, the costs are likely to stay high. If you bid one of these jobs, be prepared for some significant front end hardware expenses, and a learning curve on the materials, as it's likely you'll break at least one, and probably more. Even a small bit on the surface when trying to snap one can lead to the panel snapping, so cleanliness is super critical as it would be with any thin glass. It was kind of scary how flexible the panels were - pick up one end, and you may have to lift more than a few inches to get the whole thing off of the table!
     
    angelo polinario likes this.
  6. edwardh1

    edwardh1 Member

    Joined:
    Jul 21, 2006
    Location:
    South Carolina
  7. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    Why what? Why make tile that big? Seems like it's the same reason why some people climb mountains...because they can. They can make them, and if you want to use one, it sort of defies a lot of previous thoughts on what works and what doesn't.
     
    angelo polinario likes this.
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    Here are a few pictures that show some of the equipment used to deal with large format tile. Note the shape of the notches on the trowel, and what they look like when on the wall. Also, note that the notches were made towards the 'short' side of the tile so that any air trapped will be easier to get out so the tile can be properly set into the mortar. The tile cutter needs to be started with the cutter head on the tile, then back off the edge - cutting from off the edge onto the tile will chip it. You can run the cutter off the other end. You essentially treat it like a large piece of glass, and you can either try to snap the tile along the cut, or use some special pliers to start the crack from one end. You can actually hear it starting to snap as you slowly press the pliers together. If your cut was smooth with fairly even pressure, you'll get a nice clean cut. It takes a bit of practice. If you're dealing with less than a full, large format tile, you'd use glazier cups (fancy suction cups) to handle the tile instead of the larger, full-tile frame. Tile cutter.jpg Tile frame.jpg Trowel.jpg Tile cutter.jpg Trowel.jpg Vibrating tile to set.jpg
     
    angelo polinario likes this.
  9. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Joined:
    Sep 2, 2004
    Occupation:
    Retired Systems engineer for defense industry.
    Location:
    New England
    As more and more of these large format tile are being produced and used in the field, the procedures and recommendations are evolving. I have not taken any further training on this, so this information may no longer be valid. It should still work, but may not be the best way to do it. Some manufacturers do run training classes, and Crossville Tile, being a major manufacturer does offer classes. If you're interested in this type of material and installation, you may want to call the manufacturer to find someone that has taken their class and is up to date on the latest techniques and recommendations.
     
    angelo polinario likes this.
  10. angelo polinario

    angelo polinario Water Softener Install

    Joined:
    Nov 26, 2016
    Occupation:
    Plumber
    Location:
    Ontario, Canada
  11. fullysprinklered

    fullysprinklered Active Member

    Joined:
    Jun 15, 2014
    Occupation:
    self-employed plumber-electrician doing residentia
    Location:
    Georgia
    Hey Jim, looks like Angelo wants to go camping with you.

    All teasing aside, tile that big scares the dickens out of me.
     

Share This Page