Here in a great post by Debbie Gartner, Floor Coverings International in Westchester/Western Fairfield. Debbie does an amazing job of explaining the Janka Scale of Hardness and how it relates to hardwood floors.
The Janka hardness test measures the hardness of wood. It measures the force required to embed a 0.444 inch steel ball into wood to half the ball's diameter. It is a good measurement technique to determine the relative hardness across hardwoods.
Red oak is used as the standard and its hardness is 1,290 on the Janka scale. White oak is just a bit harder at 1,360. Bamboo is a bit harder at 1,380 (see my past blog on bamboo and why there a wide spread on actual bamboo hardness) and maple a bit harder than that at 1,450.
But, if you shift toward the exotic hardwoods from South America, the woods are on a different wavelength. The popular Brazilian Cherry is 2,350 - almost twice as hard as red oak. And, Brazilian walnut comes in at 3,684 - nearly triple the hardness of red oak.
Below is a listing of many hardwoods so you can see the range of hardness. You'll also note that most of the pines (which were used a LONG time ago) are low. They are rather soft and aren't even considered hardwoods. They can dent very easily.
Also note that there are some woods such as "cherry" and "walnut" that vary greatly based on their country of origin. Brazilian Cherry and Brazilian Walnut are very HARD; conversely American Cherry and American Walnut are very SOFT and will also dent very easily. So, if you are considering cherry or walnut, be sure to investigate further.
Again, I'm having challenges attaching pictures, but if you click on the links you can see picts of those hardwoods.
Brazilian Teak/Cumaru/Brazilian Chestnut
American Walnut/Black Walnut
Southern Yellow Pine - Long leaf
Southern Yellow Pine - Short leaf
Debbie Gartner, Floor Coverings International in Westchester/Western Fairfield
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