Hardwood floors are cupping

We bought an older home last July and installed central air conditioning. The house had window air units. We had our floors refinished in October. They looked great! My problem is the floors are cupping across the width of the boards and I do not know what is going on. We noticed this in the last few months. The house is brick on pier and beam. I have been under the house and it is dry with no moisture. We live in the northern part of Louisiana. Could the air conditioning be causing this problem? And is there anything I can do to fix this situation? Thanks..

 

The National Oak Flooring Association recommends certain safeguards to prevent cupping of hardwood floors. Among these are the following: All doors and windows should be installed and closed and the HVAC running to keep the temperature and humidity at occupancy levels before installation. There should be a polyethylene moisture barrier covering the soil beneath the home if the floor is over a crawl space. There should be no standing water. If wood is stored, it should be in a dry, well ventilated area. When the wood is brought into the home, it should be placed in the rooms where it is going to be installed and allowed to acclimate to temperature and humidity levels within the home. A vapor barrier is also recommended for installation on top the subfloor and beneath the hardwood. Because hardwood is kiln dried to very low moisture levels, it is very important that all moisture problems be addressed, vapor barriers installed, the installation area have the HVAC running to control temperature and humidity levels, and that the wood acclimate. Because wood expands and contracts across the grain, it is important to leave an expansion joint around the perimeter of the room. I believe recommended humidity levels in homes is somewhere around 45-50%. If you have taken all the above safeguards and still have cupping, check the humidity level in your home. Summer months are more humid than the winter months, and some expansion is expected. Perhaps the addition of a dehumidier will reduce the cupping of your wood. Good luck.