Wavy appearance / waves on hardwood floor

Q: My hickory 4-inch-board floors were installed in December 2005 in a brand new home. The boards are not laying completely flat. They have a wavy-like appearance and you can feel the waves with your hands. I noticed the waves on hardwood floor probably a month or so after installation.

I have been waiting, thinking they might flatten out in time. Also, I hear loud “cracking sounds” coming from the flooring from time to time. Could you tell me what caused this and if there is anything that can be done about it?

A: It sounds to me that you are describing “cupping” where the edges of the boards curl or raise. This is an indication of a moisture issue. The boards are expanding from excess moisture and pressure. Is this floor installed over a crawl space? I would do 2 things at this point. Go to your nearest electronics store and purchase a little device called a hygrometer, which gives you the temperature and relative humidity of the room. Place it on the floor for an hour or so to get a reading. Run a dehumidifier. If you had a moisture meter, I bet the reading of the floor would be over 9%.

Follow-up Q: The floor was installed over a poured concrete basement. The floor was installed in December, though, and it was not very humid then. Will it ever flatten out or will I just have to live with it? I doubt that the installer would do anything about it or maybe he couldn’t. I had been running the heat and air, however I live in Atlanta, Georgia area and it does get hot and humid here. I will buy a hygrometer and see what it registers. Will the dehumidifier make the boards lie flat again? I have a dehumidifier in the basement, but not the main floor of house where wood is.

A: One never knows for sure if a floor will flatten out. But the sooner you get on it and remove or expedite the transfer of moisture, the better are the odds.

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