Frederick M. Hueston, PhD

The old golf-ball test reliably detects poorly set tiles.

The old golf-ball test reliably detects poorly set tiles.

I was sitting at the Harley dealership waiting for my bike to get worked on (yes, this ole man still rides a Harley) when I noticed one of the mechanics pacing back and forth in front of one of the customers. It looked like he wanted to say something to one of the people in the waiting room. I watched him pace back and forth, and he finally approached this gentleman in a three-piece suit. I casually edged closer and overheard this conversation.

Mechanic: “Doc, I just tore your Harley apart, put in all new pistons, new bearings, etc. How come I get paid less than you do, as a surgeon? It’s pretty much the same thing.”

Doc: “You’re right, lad. Now try doing all that with the engine running!”

I found this pretty amusing. Little did I know that later that day, I would happen to see that doctor again, and thankfully not as a patient.

My bike was finally done, and this easy rider was headed back down the highway when my phone rang, and I had to pull over to answer it.

A female voice on the other end told me she had a problem where a water heater broke and they are claiming the water flooding the floor caused the tiles to be hollow. She said she was representing the insurance company, and the client was a doctor’s office (guess which doctor). I had to laugh since I get these calls all the time. Yet again, I had to explain how this “hollow tile” condition is impossible.

I tried to tell her there was no need for me to inspect the property, since I was confident the water leak did not cause the hollowness. She insisted that I meet her and do an inspection. Well, who was I to argue? I asked her where and when. Fortunately, it was right down the street from my office, so I agreed to meet her that afternoon.

I arrived at the medical office address and there was a lady waiting for me outside. She was the spitting image of Joan Rivers. I introduced myself and was expecting to hear some kind of crude joke or insult, which Joan Rivers was famous for. But this lady clearly was not a jokester and was serious as all get-out.  She shook my hand and asked me to follow her in. The office was closed, so she knocked on the door. Guess who answered it? Yup, it was the Harley-riding doc. He shook my hand and mentioned that he recognized me from the Harley dealer this morning. He asked us to come in and take a look. 

We went back to the closet where the water heater had leaked. The floor was porcelain tile that had a few areas that were cracked. In one area, the tile was completely broken apart.  I took out my trusty Acoustical Impact Tester (a golf ball) and began bouncing it on the floor. You guessed it, over 50 percent of the floor was hollow, but the flood didn’t cause it. I took Ms. Rivers outside and gave her my analysis.

“The hollow sounds are not caused by the flooding,” I said. “It was caused by a poor installation. The setting mortar is made of concrete and aggregate. If you understand anything about concrete curing, you know there is a condition called hydration. In brief, the water causes the hardening of concrete through a process called hydration. Hydration is a chemical reaction in which the major compounds in cement form chemical bonds with water molecules and become hydrates or hydration products.

“If anything, the water would cause the setting mortar to become stronger. If the tiles were debonded due to the flooding, I would have to call it Magic Water.”  (Hydration is a property I stress to my students in my stone and troubleshooting course, so I’m very familiar with what flooding can and can’t do.)

Long story short, the attorney was happy, and in the end, the Doc settled with the insurance company. Now, it’s back to that ride I missed!

The Stone Detective is a fictional character created by Dr. Frederick M. Hueston, PhD, written to be entertaining and educational. Dr. Fred 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. Send your comments to him at