We got called to a home in Beverly, MA. A gentleman was considering buying a house and he wanted me to be there while the home inspection was going on because there were a lot of cracks in the foundation floor. It was a very large house.
There were expansion joints in the floor, those are the lines you see in concrete so that it can expand and contract. Everything looked fine, I didn't see any water or anything like that. But, I noticed he had three high end dehumidifiers running down there. I asked the owner how long those had been running. He told me, "all summer." I then asked him when the cracks started to appear. His response: "midway through the summer."
I asked the home inspector if he had a moisture meter with him, some have them. We checked the moisture level of the concrete and it was the driest concrete that I have every seen. With that information, we figured out that he had dried the concrete out too much to cause cracks in the floor.
This was the first time I had seen this in 20 years.
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