All About The Janka Hardness Test

To determine the overall hardness of a particular wood species (domestic or exotic), the wood flooring industry uses the Janka hardness test. The test itself measures the force required to embed a 0.444″ steel ball into half its diameter into a piece of wood. The higher the rating, the harder and more dense the wood. While ratings do vary based on various environmental factors, they do help to gauge a particular species’s ability to withstand wear and denting; an important factor when determining how a wood floor will most likely perform under normal wear and tear conditions. 

As the chart details, by and large, exotic woods dominate this test with many South American species like Brazilian Walnut and Brazilian Teak offering some of the most dense wood floors on the market. 

Domestically, North American Hickory wins as the hardest wood species used to manufacture hardwood flooring. Of note, White Oak and Red Oak are great options to consider for projects requiring installation of a wood floor over radiant heating systems.

The corresponding chart contains a wide range of species to compare for reference.