Frederick M. Hueston, PhD

I  have been in this business for nearly 40 years, and some of the misinformation I see out there is so wrong that it’s scary. The following case is just one of the examples of contractors who are sadly misinformed on the proper installation techniques.

I was sitting in my office enjoying a cup of Chai. Yeah, I know– it’s not the cup of Jo that I usually have, but I figured I would try something new. Plus, the girl at Starbucks who asked me if I’d like to “try something different” was kinda cute. 

I was about to take my first sip when the phone rang.  The voice on the other end sounded very pompous and official. For a moment, I thought it was one of those voice-over narration guys who do movie trailers.  

Tiles coming off of floorHe said he was an insurance adjuster, had a tile floor case, and he needed my help to resolve it. 

I asked him what the problem was, and he told me he had a client that was complaining about their tiles coming off the floor. 

Wrong MortarWell, that sounded serious to me, so I told him I could be there that afternoon.  Before we hung up he told me that the tile setter was going to be there, and asked if I had a problem with that. 

Now, you have to realize that when I show up to examine a problem, tile setters are usually not very happy campers, but I didn’t object, and hoped he was going to be reasonable. I finished my Chai–which was actually pretty good–and went to get a haircut before heading over to “Don Pardo’s” job site (the voice-over guy).

I arrived at the home, which was a modest structure, nothing fancy. It was your typical Florida tract house. There was a beat-up pickup truck in the drive with dry mortar all over the bed, which I suspected was the tile setter’s ride. 

Parked next to the truck was a brand new Lexus, which I suspected was the insurance adjuster’s ride. 

Hmmm – I must be in the wrong business, I thought. But my old Woody is gaining in value by the day, so I shouldn’t complain about driving an antique!

Before I could get out of my car, a gentleman came running out of the house wearing a fancy suit. I was sure this was the insurance adjuster. He greeted me and told me to be careful what I said because the installer was in the house trying to convince the homeowner that his installation is perfect. Well now… this is going to be fun, I thought.  

We entered the house and I was introduced to the homeowner and the installer. The homeowner was wearing a golf shirt and khakis – and no, he wasn’t Jake from State Farm. The installer was holding a hammer and a chisel and he immediately started telling me how good his installation was. 

Now, before I go on, let me add that the tile was a 12 x12 inch porcelain tile. This will be important in a minute.  

The tile setter rambled on about the job, but his explanation didn’t cover what I needed to know. I asked him what thin set he used. He told me a standard thin set. I asked if he used any acrylic or latex additives, and he said no.  

Before I could ask any more questions he took the hammer he was holding and hit a tile in the center of the room. The tile not only cracked in half, but nearly flew off the floor! 

I stood there in shock, staring at the setting bed. He pointed to it and proceeded to insist that his installation was perfect. 

Before you read any further, look at the tile picture, to the right. I hope all you seasoned installers as well as you trained newbies will notice the clues.  

He pointed to the trowel marks saying that he used the proper notch size and then he said he even placed mortar dots to make sure the tile was even with no lippage. It was all I could do to keep from laughing.  

OK: for those of you who don’t know what’s wrong, here’s what I noticed, right away. First, the mortar used was the wrong mortar. Porcelain tile and stone tiles with fiberglass and resin backs will not bond with standard thin set.  

Secondly, when using a notched trowel, the tile should be installed parallel to the ridges, closing them up. So when you pull a tile up, you should see NO trowel marks. 

Lastly, the little mortar dots are a big NO-NO. They elevate the tile without supporting it, which can result in cracking.

So as I was saying, I just stood there in shock. I took a deep breath, looked at the insurance adjuster, and said I would do a report on my findings. 

Then, the installer asked me if had I found anything wrong. I just told him that it would be in my report, and I headed for the door. Oh yeah– and I took lots of pics to document the faulty install. Another case solved – but jeez, I wish more installers sought out industry-approved training and certification before unleashing their misguided notions on a trusting, unsuspecting public.

The Stone Detective is a fictional character created by Fred Hueston, written to be entertaining and educational. Dr. Fred often writes about real situations that he’s encountered in over 40 years in the industry. He has written over 33 books on stone and tile installations, fabrication and restoration and also serves as an expert for many legal cases across the world. You can send any email comments to him at