Teak wood movement, board-foot & weight calculator
- Janka
- 1,000lbf
- Density
- 38.4lb/ft³
- T/R ratio
- 2.3
- Spec. gravity
- 0.55
Teak (Tectona grandis) is an imported species. It has a Janka side hardness of 1,000 lbf, a specific gravity of 0.55, and an air-dry density near 38 lb/ft³ (615 kg/m³) (mechanical values at 12% moisture content). It shrinks 5.8% tangentially and 2.5% radially from green to oven-dry (T/R ratio 2.3), so a 12-inch flatsawn board moves about 0.14 in (≈ 1/8 in) across a 6-point moisture swing (about 6%→12% MC).
Compute Teak: movement, weight & board footage
Every number below is worked from Teak's own shrinkage and density figures, not looked up from a table — change the width, moisture swing, or board size in the calculators linked alongside.
Cross-grain movement by board width
| Board width | Flatsawn (tangential) | Quartersawn (radial) |
|---|---|---|
| 2″ | 0.023″ (≈ 1/32 in) | 0.01″ (≈ 0 in) |
| 3″ | 0.035″ (≈ 1/32 in) | 0.015″ (≈ 0 in) |
| 4″ | 0.046″ (≈ 1/32 in) | 0.02″ (≈ 1/32 in) |
| 6″ | 0.07″ (≈ 1/16 in) | 0.03″ (≈ 1/32 in) |
| 8″ | 0.093″ (≈ 3/32 in) | 0.04″ (≈ 1/32 in) |
| 10″ | 0.116″ (≈ 1/8 in) | 0.05″ (≈ 1/16 in) |
| 12″ | 0.139″ (≈ 1/8 in) | 0.06″ (≈ 1/16 in) |
| 16″ | 0.186″ (≈ 3/16 in) | 0.08″ (≈ 3/32 in) |
Need a different width or moisture swing? Run the movement calculator preloaded with Teak. At a T/R ratio of 2.32, Teak is moderately unstable — it moves substantially more tangentially than radially, so flatsawn stock is noticeably cup-prone and quartersawn stock is worth the extra cost in wide panels.
Board footage & weight, standard sizes
| Nominal size × length | Board feet | Weight |
|---|---|---|
| 1×4 × 8′ | 2.67 bd ft | 8.5 lb |
| 1×6 × 8′ | 4 bd ft | 12.8 lb |
| 1×8 × 8′ | 5.33 bd ft | 17.1 lb |
| 1×10 × 8′ | 6.67 bd ft | 21.3 lb |
| 1×12 × 8′ | 8 bd ft | 25.6 lb |
| 2×4 × 8′ | 5.33 bd ft | 17.1 lb |
| 2×6 × 8′ | 8 bd ft | 25.6 lb |
| 2×8 × 8′ | 10.67 bd ft | 34.1 lb |
Different length or size? Run the board foot calculator or the weight calculator, both preloaded with Teak.
Seasonal movement by city
| City | Driest month (EMC) | Most-humid month (EMC) | EMC swing | 12″ board movement |
|---|---|---|---|---|
| Phoenix, AZ | Jun · 4.4% | Dec · 9% | 4.6 pts | 0.107″ (≈ 3/32 in) |
| Chicago, IL | May · 12.3% | Dec · 15.1% | 2.8 pts | 0.065″ (≈ 1/16 in) |
| Miami, FL | Apr · 12.2% | Sep · 14.4% | 2.2 pts | 0.051″ (≈ 1/16 in) |
| Boston, MA | Apr · 11.5% | Sep · 12.8% | 1.3 pts | 0.03″ (≈ 1/32 in) |
| Denver, CO | Jul · 8% | Dec · 10.5% | 2.5 pts | 0.058″ (≈ 1/16 in) |
| Seattle, WA | Jul · 12% | Dec · 16.9% | 4.9 pts | 0.114″ (≈ 1/8 in) |
Driven by Teak's tangential shrinkage of 5.8%. These are outdoor equilibrium-moisture figures, so they are an upper bound — a climate-controlled interior swings less. How this is calculated.
How Teak compares
Ranked against the 196 species in the Wood Handbook tables this site carries.
- Hardness: at 1,000 lbf, Teak is harder than 52% of the 157 species with a Janka figure.
- Weight: at 38.4 lb/ft³ it is heavier than 54% of the 170 species measured — an 8-foot 1×6 board weighs about 12.8 lb.
- Stability: its T/R ratio of 2.32 is more even than 10% of the 196 species here — as humidity changes, 90% of them hold their shape more evenly.
See Teak plotted against every species we carry: the full Janka hardness chart and the full density chart .
Species with a similar working profile
Closest matches on hardness, weight and stability together — useful when Teak is unavailable or priced out.
- Silver Maple is a common substitute for Teak : 30% softer, 15% lighter, and similarly stable in service.
- Black Oak is a common substitute for Teak : 21% harder, 11% heavier, and similarly stable in service.
- Red Maple is a common substitute for Teak : nearly identical hardness, about the same weight, and more stable in service.
- Northern Red Oak is a common substitute for Teak : 29% harder, 15% heavier, and similarly stable in service.
| Species | Janka | Density | T/R |
|---|---|---|---|
| Silver Maple | 700 lbf | 32.8 | 2.4 |
| Black Oak | 1,210 lbf | 42.6 | 2.52 |
| Red Maple | 950 lbf | 37.7 | 2.05 |
| Northern Red Oak | 1,290 lbf | 44 | 2.15 |
About Teak
Teak (Tectona grandis) occurs in commercial quantities in India, Burma, Thailand, Laos, Cambodia, Vietnam, and the East Indies. Numerous plantations have been developed within its natural range and in tropical areas of Latin America and Africa, and many of these are now producing teakwood. The heartwood varies from yellow–brown to dark golden brown and eventually turns a rich brown upon exposure to air. Teakwood has a coarse uneven texture (it is ring porous), is usually straight grained, and has a distinctly oily feel. The heartwood has excellent dimensional stability and a very high degree of natural durability. Although teak is not generally used in the United States where strength is of prime importance, its properties are generally on par with those of U.S. oaks (Quercus). Teak is generally worked with moderate ease with hand and machine tools. However, the presence of silica often dulls tools. Finishing and gluing are satisfactory, although pretreatment may be necessary to ensure good bonding of finishes and glues. Teak is one of the most valuable woods, but its use is limited by scarcity and high cost. Because teak does not cause rust or corrosion when in contact with metal, it is extremely useful in the shipbuilding industry, for tanks and vats, and for fixtures that require high acid resistance. Teak is currently used in the construction of boats, furniture, flooring, decorative objects, and decorative veneer.
Properties
| Specific gravity | 0.55 |
|---|---|
| Janka hardness (side) | 1,000 lbf |
| Density (air-dry, 12% MC) | 38.4 lb/ft³ (615 kg/m³) ovendry-weight basis: 34.3 lb/ft³ |
| Weight per board foot (air-dry) | 3.2 lb |
| Radial shrinkage (green→oven-dry) | 2.5% |
| Tangential shrinkage (green→oven-dry) | 5.8% |
| Volumetric shrinkage (green→oven-dry) | 7% |
| T/R ratio (stability indicator) | 2.3 |
Shrinkage is total green-to-oven-dry (Table 4-4); strength values are at 12% MC. Full bases and the derivation formulas are on the methodology page.
Data: USDA Forest Products Laboratory, Wood Handbook FPL-GTR-282 (2021), public domain.