What is the Janka hardness rating?
The Janka test measures how much force is needed to press a steel ball into wood. It is commonly used to compare resistance to indentation, especially when considering timber flooring.
Generally, harder timber is more resistant to dents, but hardness is only one consideration. Durability, stability, moisture exposure, finish and the intended application also matter.
Indicative timber examples
| Relative hardness | Examples often considered | What it may mean |
|---|---|---|
| Very hard | Ironbark, Spotted Gum | Often considered for higher-wear applications. |
| Hard | Blackbutt, Jarrah | May suit many residential uses, depending on specifications. |
| Moderate / softer | Selected ash and oak timbers | Appearance, coatings and care become particularly important. |
Important: These are broad examples, not certified test values or a product specification. Ratings vary within species and depend on the test method; verify actual values and suitability with the timber supplier and product documentation.
How to use hardness information
- Think about traffic, furniture, pets and the likelihood of impacts.
- Balance your preferred look with durability, stability and price.
- Check moisture management and finishing recommendations.
- For outdoor or structural projects, use the relevant durability and structural standards, not Janka hardness alone.
