Janka Hardness Test

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The Janka Hardness test shown below is done in accordance with ASTM D 1037-7 testing methods. Janka Hardness test shown come from the NWFA Species Guide and were done by the U.S. Department of Agriculture for the Forest Products Laboratory, which is a division of the U.S. Government.  These ratings are all done by a independent third party not by any particuliar company. The lumber stock that was tested ranged from 1" to 2" thick. It important to note that no flooring is ever tested.. (Resulting Janka Hardness Numbers below are an average.) There is a standard deviation associated with each species, but the standard deviation numbers are not published by any source. Other factors that can affect how engineered floor performs: type of core for engineered flooring like: pine, hdf, popular, oak, or birch.. Finally, cut, grain direction and thickness of the floor or top wear surface effect the hardness of flooring.  The chart is not to be considered an absolute; it is meant to help people understand which woods are harder than others. Further information about Janka Hardness can be obtained by contacting the National Wood Flooring Association technical service department at www.nwfa.org.