Moisture Acclimation of Wood in Different Parts of the Country

Posted by Tom Laurenzi on Oct 30, 2015 10:00:00 AM

Acclimation of WoodAs most of us know, wood is an environmentally vulnerable material; it can expand and contract dependent on the environmental conditions, indoors and outdoors. Wood is a hygroscopic material which means that it attracts and holds moisture from its environment changing, its physical properties.

These changes can make it difficult to keep wood’s dimensions stable and moisture levels equal. Using a wood moisture meter enables you to attain a proper reading of the wood’s moisture content, ensuring its stability over a given period of time.

The idea is to get the wood acclimated to its environment so that it does not absorb or expel moisture too quickly. When wood absorbs or sheds moisture too quickly, the wood can become deformed and experience severe buckling or warping as a result.

What is Wood Acclimation?

The acclimation process allows air to circulate around the wood, giving it a chance to expand or contract until the wood reaches the proper moisture levels according to its wood type before setting it in place. The acclimation process usually takes five days; however, it can take more than five days depending on the environmental conditions and the type of wood being acclimated. 

A general rule of thumb is to acclimate the wood in a room that has a temperature between sixty and eighty degrees Fahrenheit. However, the acclimation time varies depending on the wood (solid, engineered and species) being installed.

The idea is for the lumber manufacturer, distributer and installer to acclimate the wood prior to shipment and installation to have accurate placement and installation as a means to avoid disgruntled customers and loss of business.

Ideally, when you are checking the moisture content in wood flooring, keeping the aesthetic appeal of the wood is important. Using a pinless moisture meter would be ideal for checking flooring prior to installation and to ensure the preservation of the wood’s appearance.

What are the Different Environments in USA?

When traveling across country, we can feel the different climates that the Unites States is made of. In the more southern regions, there is a higher humidity percentage.  In the western regions, it is a drier desert like climate and requires different acclimation needs.

For most of the United States, average relative humidity is between 40%- 45%. This relative humidity percentage requires wood to have about 8% moisture content. However, there are exceptions to this. One example would be the California coastline, which has a relative humidity of approximately 58%- 63% which would require about 11% moisture content in wood.

Another example is that when we measure the relative humidity on the east side of California and its surrounding states, we notice that it has a 30% relative humidity which would require about 6% moisture content in the wood being used.

A third example is found in southeastern regions such as: Florida, Texas, Louisiana, and Georgia, of the United States mirrors the California coastline with a relative humidity percentile between 58% and 63%, requiring the wood being used in that region to have an average moisture content of 11%.

The relative humidity in the United States changes, affecting the hygroscopic material we use: wood.  Wood has the ability to expand and contract based on the relative humidity in the area it is in changing the average moisture content the wood has.

 It is important to acclimate the wood being used, and it is even more important to use a good moisture meter throughout the acclimation process in order to have an accurate %MC reading for wood.

You can find a good information source where you can learn more about how to check lumber acclimation using a moisture meter by clicking the link here.


Measuring Moisture in Flooring Systems

Topics: Wood Flooring Moisture Meter woodwork