Wood is a natural material that reacts to moisture gain and loss by expanding or shrinking. The moisture content of flooring at the time of manufacture is one of the most critical factors determining how that floor will perform once it is installed.

Flooring manufactured at too high a moisture content will tend to shrink, possibly causing unacceptable gaps in the floor. If the flooring is too dry, it will gain moisture and expand which could result in cupping or even buckling. NOFMA standards call for moisture content at the time of manufacture to be consistent and within the range of site conditions likely to be encountered so that the end-user can be assured the flooring will perform as expected.

TIP: If flooring is intended to be used in extreme conditions, check with your contractor about specifying a moisture content level most suitable for those conditions. In some instances (such as below-grade installations) solid wood flooring may not be appropriate.

Grading and Milling Standards
NOFMA Wood Flooring Grades