Teak
Tectona grandis
Teak measures 1,000 lbf on the Janka scale, 22% softer than northern red oak.
- Only macawood, redwood (old-growth) and western redcedar lose less volume on drying, and only six woods shrink less through the thickness.
- It is softer than its weight suggests: the trend across all 155 woods puts a specific gravity of 0.55 near 1,290 lbf.
- Drying barely changes its hardness: from 930 lbf green, it gains only 8% by 12% moisture, against a median of 31%.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
TeakImported woods medianOther woods
Cupping tendency
2.3214th highest of 15533% above the imported woods median1.092.90Shrinkage across the face
5.8%radial 2.5%19th lowest of 15527% below the imported woods median3.5%12.7%Bending strength
14,600 psi100.7 MPa55th strongest of 1554,300 psi29,900 psiDensity
0.5560th heaviest of 1550.250.96Stiffness
1.55 M psi10.7 GPa61st most flexible of 1550.54 M psi4.06 M psiJanka hardness
1,000 lbf4,448 N75th hardest of 15544th of 65 imported woods240 lbf3,680 lbf
How much it moves
Total movement is small, but most of it runs along the rings (T/R 2.32), so a flatsawn board still loses 2.3 times the width of a quartersawn one.
0.35 in.
off a 6-inch flatsawn board, green to oven-dry; quartersawn 0.15 in.
- Tangential
- 5.8%
- Radial
- 2.5%
- Volume
- 7.0%
- T/R ratio
- 2.32 (142nd most stable of 155)
End view, shrinkage drawn 3× life size.
Laboratory values
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Compression parallel to grain | 5,960psi | 8,410psi | +41% | 58MPa |
| Shear parallel to grain | 1,290psi | 1,890psi | +47% | 13MPa |
| Modulus of rupture | 11,600psi | 14,600psi | +26% | 100.7MPa |
| Modulus of elasticity | 1.37M psi | 1.55M psi | +13% | 10.7GPa |
| Work to maximum load | 13.4in-lbf/in³ | 12in-lbf/in³ | −10% | 82.7kJ/m³ |
| Side hardness | 930lbf | 1,000lbf | +8% | 4,448N |
Wood Handbook Table 5-5b, Table 4-4. Data & method · Guides