Understanding the Janka Rating Scale for Hardwood

06/15/2021

The Janka hardness test is the most commonly used method to uncover valuable information about the hardness of any particular type of wood species. This test is extremely useful while determining which type of wood is best suited for your home. A thorough understanding of the Janka rating scale for hardwood helps us make better decisions about our hardwood floors.

How does it Work?

Gabriel Janka invented this test in 1906, and it was standardised later by the ASTM (American Society for Testing and Materials). It was developed as a method for measuring a specific type of wood’s resistance to wear and denting.  A 0.444″ steel ball and piece of wood with dimensions of 2″ x 2″ x 6″ is used in this test to determine how hard the wood is. The Janka reading of a specific type of wood is the force required in pounds per square inch (PSI) to push the ball halfway into the piece of wood.

Comparing Janka Ratings:

In general, the harder the wood, the greater is the force required to embed the steel ball into it. As hardness is directly correlated with durability, wood floors that have higher Janka rating offer better resistance to normal wear and tear.

While estimating installation time and cost, the Janka ratings are taken into consideration by the hardwood flooring installers. As a result of their greater natural resistance, a seasoned installer and the right tools are essential for the installation of hardwood flooring with higher ratings. This is also the reason why compared to other wood varieties, wood floors with high Janka ratings are more expensive.   

Range of the Scale:   

The Janka scale of hardness starts at zero, representing the softest of wood that can be dented or scratched rather easily. However, please note that no wood in reality has zero Janka rating. The highest rating on this scale is 4000, and refers to woods with extreme hardness. This type of hardwood is also not suitable for flooring as they are extremely difficult to saw.  

Good and Bad Janka Hardness Rating:

While opting for wood flooring, an idea of the Janka scale rating can help us understand the strength of the floor and its ability to withstand wear and tear over the years. In general, any type of wood with a rating of 1000 or higher is considered to be the globally accepted standard for flooring related applications. Anything less than a rating of 1000 is not considered for flooring. However, it is important to note that the Janka rating is no more than an indication because the durability and appearance of a floor over time depends not just on its hardness. 

Mentioned below are some of the most common wood species and their Janka hardness rating.

Brazilian Walnut: 3684

Ebony: 3220

Brazilian Redwood: 3190

Red Mahogany: 2697

Sydney Blue Gum: 2023

Tallowwood: 1933

Hickory: 1820

 Rosewood: 1780

Blackwood: 1720

Red Pine: 1630

Sweet Birch: 1470

Hard Maple: 1450

Natural Bamboo: 1380

White Oak: 1360

Red Oak: 1290

Black Walnut: 1010

Teak: 1000

If you have more questions related to hardwood flooring options for your home, please contact our experts at Enoak. We have an exquisite range of French oak flooring created as per your taste.