Timber Durability & Hardness
Hardness
- VS (very soft)
- 480 kg/m3 or less
- S (soft)
- 485 - 560 kg/m3
- F (firm)
- 565 - 680 kg/m3
- M (moderate)
- 685 - 800 kg/m3
- H (hard)
- 805 - 960 kg/m3
- VH (very hard)
- 965 kg/m3 or more
Strength Groups
- S
- Unseasoned - There are seven groups ranging downward from S1 to S7.
- SD
- Seasoned - There are eight groups ranging downward from SD1 to SD8.
Joint Groups
There are six groups ranging downward from 1 to 6; they indicate mechanical properties for jointing purposes in engineering design.
