Let me start off by saying that I am NOT a flooring expert or installer, I am a homeowner looking for answers.
About 3 years ago, my home was built in southern Louisiana with reclaimed/antique pine hardwood flooring (7" planks) glued to the concrete slab. The house has total encapsulation foam insulation and a combination AC/dehumidifier. The house stays around 45% humidity.
Within a few weeks of moving in, we started having cupping problems. It got so severe that some of the planks came unglued from the slab due to the pressure. Because the contractor did not use a moisture barrier over the concrete (even though the glue he used had a moisture barrier in it), he assumed that the problem was due to moisture coming up through the slab into the wood. So after ripping out the old floor, he laid Bostik's MVP as a moisture barrier and then glued the new planks on top of that.
Fast forward 5-6 months later, and we are having more cupping problems. They are not as severe, but still very bad. The contractor had no idea what was happening, so he had a technical rep from Bostik inspect the floors. The report from Bostik said:
With the use of a Mini-Ligno DX/C Moisture Pin Meter, adjusted for species, readings were taken of the wood flooring. The results ranged from 5.00-5.40 %.
With the use of a Mini-Ligno DX/C Moisture Pin Meter, adjusted for species, a reading was taken with long probes of the wood flooring. Moisture Content measured at a depth of approximately 5/8” were within the expected range. This floor shows signs of “dry cupping” as the face was significantly dryer than readings taken at depth.
Cupping of solid wood flooring is a moisture differential within individual pieces of wood flooring. The moisture content was very low, dry on the surface. Readings taken within the flooring are consistent with what you would expect in your part of the country.
Can someone explain what this means? The contractor has no idea and will not install wood flooring in my home because of the liability. At this point, I would like to install engineered wood , but I am concerned we will continue to have this problem. What should I do?
edit: photos here: https://i.stack.imgur.com/a7CUG.jpg