As editor of this publication, each issue of TILE Magazine - including its enewsletters and website - is put together with forethought, planning and the passion to put forth superior information to our readers.

Fortunately, I am blessed to work with several well-respected columnists, including Michael Byrne and Dave Gobis. They are industry veterans who are on top of their game; yet still make time to help those who want to tap into their knowledge. For their well-honed expertise, caring nature and dedication, I thank them.

As an example of their hard work and dedication to the tile and stone industry as a whole, I would like to share a couple of notes written by our readers to Dave Gobis. If anything, we’ll all continue learning and asking questions to better ourselves, just as these two readers did.

Brent Eastwood, president of Villi USA, LLC, asks:

Hi Dave,
I read with interest your article in TILE Magazine today on problems encountered in various tile-setting jobs and wondered if you have a “definitive” paper on setting glass tile? We are a manufacturer, importer and distributor of glass tile and often are faced with problems caused by bad tile installations. This is usually just a lack of knowledge on the part of the installer and a need to educate on the difference between working with glass versus working with ceramic.

I would be interested to hear from you on this. Many thanks.

Dave’s response:

Personally, I have not written extensively about it though I am well versed in the installation and issues of glass. However, I would stop short of saying expert on that particular product.

We have had many industry discussions for a number of years. Thinset has many limitations and foremost, shrinkage issues when setting glass. This is typically compounded by poor preparation and installation. Work actively continues on developing glass tile standards for the U.S. market. Once we have achieved that, U.S. thinset manufacturers are prepared to invest more in research. The only standards currently available are for glass mosaics of which there are three different installation methods under ANSI standards.

I am in complete agreement, a tile installer does not equate to a glass tile installer. However, even the best glass installer may have problems given the limitations in our depth knowledge about the action and reaction of glass, particularly in larger formats. Our phones start ringing when the tile gets over 3”x3” and in particular any rectangles.

I am not sure what I can offer you that would make your life easier and company more profitable at this point other than point out the issues as we know them.

Another reader shares his thoughts on uninformed tile installers:

I liked your article in TILE Magazine this month. And it was so true, especially the part about people slacking in quality just to get the job so they can pay the bills. What I find here is that more people with no knowledge pick up a trowel and bucket and say "I am poor therefore I tile."

I narrowly helped a friend of mine who is an installer, a newer one, but trying very hard to learn the right way, avert certain disaster with some glass tile he was having trouble with.

He called me to asked about cutting it because he had encountered some trouble with a foil color backing (something I have never seen in glass tile). Anyway he tried about everything he could think of to cut it (even a new lapidary blade) and the foil just kept flaking off. I suggested it might be an inferior product.

He eventually had to work the design so there were little if no cuts and then he called to tell me how it was going and during the conversation he says, "Well, I think this will work, so I am just taking the lid off the can..."

Alarm bells went off in my head and I replied, "Uh, you aren’t using mastic are you?" A pause. "I was going to. Should I not?"

I spent the rest of the conversation telling him the woes of glass and mastic and how they were mortal enemies and no good had ever come of a meeting between the two. Here is the sad part. He had no idea that it was a bad idea because the can didn’t say so and the tile sales company he was doing the job for gave him the mastic with the glass and said the mastic would work for everything. I told him to double check my info with Jesse at Winco (whom you have met but may not remember). Winco sells the mastic. Jesse assured him that mastic and glass was a bad idea and something along the lines of "No, no, no!"

Anyway, interesting that the places that sell tile (really expensive tile too) don’t seem to know anymore about the products they sell than some of the installers out there.

Jamey Walther, Florida Tile, Inc. sales rep, asks:

In your most recent article in TILE Magazine, you mentioned that a thinset’s bond strength decreases as the mortar bed becomes thicker. I have known and understood for some time that thinset will shrink with devastating results when applied too thick.

But I had never heard that the bond strength becomes weaker when applied over the recommended thickness.

Since I consider it my job to inform my customers of every possible way to ensure a correct installation of my product, I would like to know if you could give me a brief explanation on the causes of this decreasing bond strength. If it is too involved, could you direct me to a source?

Thanks for the help. I enjoy reading your articles. They help me “preach the truth” to an ever increasing audience of non-believers.

P.S. When do you think this industry or the government will require some type of certification to become a licensed tile contractor?

Dave responds:

The bond strength issue is similar to the strength of a masonry sand and cement mortar joint to a concrete walk or road. The road is the same as the brick joint, just bigger aggregate. Shrinkage itself can and does cause bond loss. Thinset is designed for a specific profile thickness range.

With standard thinset that is 3/32 to 3/8” generally speaking. Once that is exceeded, the crystalline structure typically needs to be increased in size or mass, that is a mix design. There are ways to compensate, such as polymers and certain types of fillers, but generally from a cost efficient perspective, it is bigger aggregate that also helps the shrinkage issue.

Bonding material design has grown increasingly complex. There are going to be some new designations down the road. The move towards ISO standards is a positive step but in the opinion of most technical people in the U.S. market, does not go far enough. It does not contain a shrinkage standard and shears are based on tensile pull rather than lateral shear.

Note: If you have any thoughts or concerns you would like to share, then I urge you to either email me or our columnists (their email addresses are listed below their columns).