Imbuia wood movement calculator
- Janka
- —
- Density
- —
- T/R ratio
- 2.2
- Spec. gravity
- —
Imbuia (Phoebe porosa) is an imported species. The Wood Handbook strength tables list no matched specific gravity or hardness for it, so those fields are shown as “—”. It shrinks 6% tangentially and 2.7% radially from green to oven-dry (T/R ratio 2.2), so a 12-inch flatsawn board moves about 0.14 in (≈ 5/32 in) across a 6-point moisture swing (about 6%→12% MC).
Compute Imbuia: movement, weight & board footage
Every number below is worked from Imbuia'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″ | 0.024″ (≈ 1/32 in) | 0.011″ (≈ 0 in) |
| 3″ | 0.036″ (≈ 1/32 in) | 0.016″ (≈ 1/32 in) |
| 4″ | 0.048″ (≈ 1/16 in) | 0.022″ (≈ 1/32 in) |
| 6″ | 0.072″ (≈ 1/16 in) | 0.032″ (≈ 1/32 in) |
| 8″ | 0.096″ (≈ 3/32 in) | 0.043″ (≈ 1/32 in) |
| 10″ | 0.12″ (≈ 1/8 in) | 0.054″ (≈ 1/16 in) |
| 12″ | 0.144″ (≈ 5/32 in) | 0.065″ (≈ 1/16 in) |
| 16″ | 0.192″ (≈ 3/16 in) | 0.086″ (≈ 3/32 in) |
Need a different width or moisture swing? Run the movement calculator preloaded with Imbuia. At a T/R ratio of 2.22, Imbuia 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 and weight aren't shown for Imbuia — the Wood Handbook strength tables carry no matched density for it, so a weight figure here would be invented rather than computed. The board foot calculator still works without a species; board feet don't depend on density.
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 | 0.11″ (≈ 1/8 in) |
| Chicago, IL | May · 12.3% | Dec · 15.1% | 2.8 pts | 0.067″ (≈ 1/16 in) |
| Miami, FL | Apr · 12.2% | Sep · 14.4% | 2.2 pts | 0.053″ (≈ 1/16 in) |
| Boston, MA | Apr · 11.5% | Sep · 12.8% | 1.3 pts | 0.031″ (≈ 1/32 in) |
| Denver, CO | Jul · 8% | Dec · 10.5% | 2.5 pts | 0.06″ (≈ 1/16 in) |
| Seattle, WA | Jul · 12% | Dec · 16.9% | 4.9 pts | 0.118″ (≈ 1/8 in) |
Driven by Imbuia's tangential shrinkage of 6%. These are outdoor equilibrium-moisture figures, so they are an upper bound — a climate-controlled interior swings less. How this is calculated.
How Imbuia compares
Ranked against the 196 species in the Wood Handbook tables this site carries.
- Stability: its T/R ratio of 2.22 is more even than 15% of the 196 species here — as humidity changes, 85% of them hold their shape more evenly.
Properties
| Specific gravity | — |
|---|---|
| Janka hardness (side) | — |
| Density (air-dry, 12% MC) | — |
| Weight per board foot (air-dry) | — |
| Radial shrinkage (green→oven-dry) | 2.7% |
| Tangential shrinkage (green→oven-dry) | 6% |
| Volumetric shrinkage (green→oven-dry) | 9% |
| T/R ratio (stability indicator) | 2.2 |
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. Values shown as “—” have no matched entry in the Wood Handbook strength tables (5-3b/5-5b).
Data: USDA Forest Products Laboratory, Wood Handbook FPL-GTR-282 (2021), public domain.