What is the maximum allowable difference in moisture content between flooring and sub-floor prior to gluing?

The maximum allowable difference in moisture content between flooring and sub-floor prior to gluing is 4%. This standard is critical because significant moisture discrepancies can lead to issues such as warping, buckling, or delamination of the flooring material once it is installed. When the moisture levels of the two components are not closely aligned, it can cause the adhesive not to bond effectively, resulting in failure of the flooring over time.

Understanding and adhering to this moisture content guideline helps ensure a successful flooring installation. This is particularly important in environments that are prone to humidity fluctuations, as wood and other flooring materials can absorb or release moisture, affecting their integrity. Maintaining this 4% moisture content difference is essential for longevity and performance of the flooring system.