I am not sure where I first heard the saying, “Get the home ready for the wood, and the wood ready for the home,” but I have heard it 1000 times. Maybe it’s because acclimation is really this simple. The NWFA and most manufacturers have done a great job of making the indoor requirements needed for wood floors to perform available. And with the internet, we have no excuses not to know what the environment should be.
Let’s start with the tools needed to assure proper acclimation. First, a hygrometer/ thermometer, this will give you the relative humidity and the temperature for the environment of the home. When your temperature and relative humidity meet the NWFA/manufacturer recommendations for the environment of the home, you will be ready to bring the wood into the home (30 percent RH – 50 percent RH and 60°F – 80°F note: this can vary from manufacturer to manufacturer, and you will always defer to the manufacturer over the NWFA).
Next, you will need a moisture meter to test the wood. Most of them will either have an adjustment to calibrate for a specific species or will have a conversion chart. Some have pins, and some are pinless. This test will need to be done in multiple boards following the meter manufacturer’s requirements. These readings will tell you when the floor will be ready for the home. Using the chart below, you can convert your temperature and relative humidity into the Equilibrium Moisture Content (EMC) needed for your floor. This goes for your subfloor also.
So, how long will it take for the wood floor to acclimate? Sometimes giving an accurate timeline can be a guessing game. This is something that you will learn to guestimate based on your experience in your region. The home’s environment, starting moisture content of your wood floor, and also the species all play a part in the amount of time needed for acclimation.
A couple of more things to pay attention to, make sure that your meters are calibrated and in good working order. The subfloor must also be at the appropriate moisture content. Both concrete and wood subfloors need to be checked. This may mean that you need more meters to test this properly.
The biggest thing that I can emphasize is that you document everything. These moisture readings are like a photograph in time and can change. Most of the materials we are working with will change dimensionally due to either temperature, moisture content changes, or both. Proper documentation can and will protect you from potential future problems.
So to recap, “Get the home ready for the wood, and the wood ready for the home!” It’s simple!