Wood is a natural product with a high percentage of water (humidity) while it is alive. Before being milled it is kiln-dried to remove moisture. Then it travels across the country or halfway around the world to your home, transported in unheated trucks and other conveyances. By the time it gets to your house the humidity or moisture level may have changed. That’s why some woods are well packaged with foam sheets between boards to absorb some of the excess moisture. It’s imperative that you maintain, or at least allow for, humidity changes in your wood. For example, before installing the wood, bring it into the living area for at least 24 hours so the wood’s humidity and temperature can stabilize. Also, in homes located in higher humidity regions, allow more than the standard 1/4-in. space between the flooring and the perimeter walls. You may need as much as 1/2-in. of spacing to allow for expansion, especially in larger rooms. In addition, install a humidity gauge in your house to keep an eye on the humidity of the air above your new flooring. If in doubt about preferred humidity levels, contact the flooring material’s manufacturer.
Make sure the flooring material is acclimated to the temperature and humidity of the installation area for at least 24 hours. Also, keep the materials tightly bundled until you’re ready to install them. Otherwise, boards may warp or bow during installation. Hardwoods are especially sensitive to changes in humidity. Read the manufacturer’s information about preferred humidity levels and installation temperatures.