Acclimation of the flooring: Unlike ceramic tiles, stone, or plastic products, wood flooring is a dynamic, hygroscopic material. Like a sponge, its shape can be adversely affected as a result of environmental, temperature and humidity changes. Because of this, it is in your best interest to ensure that the flooring be climate controlled with temperatures of 60° to 80° F, preferably 70° F, and humidity of 30% to 50%, preferably maintained at 45%. When wood is correctly acclimated to these target values it becomes relatively dormant, neither expanding nor shrinking.
The HVAC ventilation system must be fully operational providing normal air flow in all rooms. Also if the flooring was shipped with protective plastic wrap, open the ends of the container exposing it to air flow. Wood, laminate, and cork flooring should NEVER be stored directly on bare concrete substrates or stored in garages or out-buildings without climate control. Boards stored in this fashion can absorb moisture and be edge-cupped right in the box. The point of acclimating is to condition wood products to "normal living conditions" the floor will experience once the structure is occupied, before fastening.
Moisture testing and acclimation go hand-in-hand: Next, only after the new flooring has been properly acclimated and the true moisture values of the flooring have been verified through testing, is the flooring ready for installation. With these values in mind the installation could actually take place the day of delivery or several days later, depending on the species. It is not unusual for oily or denser species to take one to two weeks of in-home monitored acclimation before installation.
Pre-finished flooring is shipped having 6-9% MC Moisture content. To start the installation, the goal is for the installer to establish a MC balance between the flooring and subflooring. The subfloor moisture content should not exceed 12%. With this in mind, the moisture content of a 2 1/4" wide board should be no greater than a 4% difference or a balance of the wood subfloor. For boards 3" or wider, the moisture content must be within a 2% balance of the subfloor. When the moisture balance is achieved then the installation can begin. If the balance varies more than the measurements outlined, the installer should hold off the installation until the wood flooring and subfloor has achieved an MC equilibrium or balance.
Thank you for your inquiry
Answered on 8/22/2013 by cc-3