Why Floor Installers Need Quantitative Moisture Readings
Another industry that would benefit from quantitative moisture measurement is the flooring industry. Wood floor installers often require accurate measurements of the moisture content of the wood they are working with as well as relative humidity (RH) for an accurate assessment of the conditions at the installation site.
Why is quantitative moisture measurement so important? The main reason is that, being a hygroscopic material, wood tends to absorb or release moisture until it reaches equilibrium with the environment. This is known as the equilibrium moisture content (EMC) of the wood, and this value will vary from one job site to another, so floor installers need to check the RH conditions of their wood and each job site.
If a wooden floor is installed too far from the EMC values of the current installation location, a number of failures can occur, including:
Discoloration. In some wood floors, moisture can cause dark or faded spots. This destroys the appeal of the floor and can be a harbinger of other floor failures.
Warped. As the wood begins to absorb moisture, the wood will begin to warp and pull away from the floor. In most cases, the intervals are small. However, in some rare and extreme cases, the wood may completely separate from the floor if there is an external source of moisture.
crowned. When the center of a wood floor has more moisture than the edges, the center will swell and form a small bulge. This is called "crowding".
cupping. When there is more water at the edges of a plank than in the center, the edges may rise as the plank expands. This can also cause the boards to press against each other, creating a wavy appearance.
Continuous water condensation. As wood floors release excess moisture, it may condense on the wood surface.
For a floor installer, any of these issues can cause a callback, which involves wasting a lot of time, labor, and resources replacing damaged wood floors.
Therefore, it is important to perform quantitative moisture measurements on the %MC of wood floors. Also remember: Quantitative measurements of RH conditions should be made at the job site to help determine the EMC of the wood.
Considerations: Since wood floor installers can handle many types of wood, having a "wood moisture meter" alone is not enough. Even at the exact same moisture content, different types of wood will have different readings. Therefore, if the goal is to achieve quantitative moisture measurements, it is important to consider the correction for wood species. Some high-end wood moisture meters have built-in species corrections, while others require manual adjustments using species correction tables.
