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Flooring 101 Home Floor Care and Repairs Problems Cracks in Boards Under Finish

Cracks in Boards Under Finish

Why do I have cracks in my boards and under the finish?

The problems indicate site-related over-drying of the wood resulting in splitting of the top clear-coat called "checking". Short of re-sanding, Liquid scratch covers can be used to soften splits that create a white line. Actually, this over drying condition can be managed by maintaining correct acclimation of your flooring for example; in-door temperatures should be maintained at 60-80 F and humidity at 30-50%

Wood floor acclimation is a required pre-installation process that allows the new flooring to adjust itself to the indoor environment (heating or air conditioning). The details of the process vary slightly among flooring manufacturers, but the basic concept is the same. The consensus is to place your flooring in the room where it will be installed not the garage, for a length of time with the temperature at 60-80 F the indoor humidity at 30-50%. For ease of monitoring, humidity Meters or hygrometers can be purchased for as little as $10.00 at many home repair centers. Wood species specific moisture meters can be used to determine if the wood is at proper moisture content prior to installation. These meters can also help determine if there is a moisture issue after installation.

Even after the installation because wood is fibrous, it continues to absorb or releases moisture trying to equalizes or balance itself to the humidity of its environment. As the humidity level begins to decrease, wood releases moisture, and when its moisture content drops, the wood begins to shrink producing board edge gaps, splits that crack the surface finishes, a symptom of over-dry wood. If the moisture content and the humidity level increases, the wood may absorb moisture and begin to swell, cup or buckle. Once floor boards reach a normal saturation point of 6% -12% (depending on the region of the country) the EMC or Equalized Moisture Content the wood flooring becomes relatively stable and the flooring can now be installed. Installing solid wood outside these established values can present a shock to the wood's cell structure, resulting in problems after the installation.

Therefore it is best to think of wood floor acclimation as a continuous maintenance process. Interestingly these same humidity and temperature levels are also ideal for humans too!

Please feel free to contact us if you have any additional installation questions.

Tech and Install

Flooring 101 Home Floor Care and Repairs Problems Cracks in Boards Under Finish