Grand fir
Abies grandis
Grand fir measures 490 lbf on the Janka scale, about 38% as hard as northern red oak.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
Grand firU.S. softwoods medianOther woods
Density
0.350.37 at 12% MC17th lightest of 1550.250.96Bending strength
8,900 psi61.4 MPa22nd weakest of 1554,300 psi29,900 psiCupping tendency
2.2123rd highest of 1551.092.90Janka hardness
490 lbf2,180 N27th softest of 15520th of 37 U.S. softwoods240 lbf3,680 lbfStiffness
1.57 M psi10.8 GPa63rd most flexible of 1550.54 M psi4.06 M psiShrinkage across the face
7.5%radial 3.4%65th lowest of 1553.5%12.7%
For its weight: stiffness-to-weight 4.49 (6th of 155).
How much it moves
Most of its movement runs along the rings (T/R 2.21): quartersawn, the same board would lose 0.20 in. instead of 0.45 in.
0.45 in.
off a 6-inch flatsawn board, green to oven-dry
- Tangential
- 7.5%
- Radial
- 3.4%
- Volume
- 11.0%
- T/R ratio
- 2.21 (131st most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- White fir
2% softer · 6% heavier · shrinks 0.5 points less across the face
- Western white pine
14% softer · same density · shrinks 0.1 points less across the face
- Balsam fir
22% softer · 6% lighter · shrinks 0.6 points less across the face
Among the true firs
2nd hardest of 7, lbf.
Laboratory values
Its most unusual laboratory figure is shear strength: 9th lowest of the 154 woods with a published value.
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Shear parallel to grain | 740psi | 900psi | +22% | 6.20MPa |
| Tension perpendicular | 240psi | 240psi | ±0% | 1.70MPa |
| Modulus of rupture | 5,800psi | 8,900psi | +53% | 61.4MPa |
| Compression parallel to grain | 2,940psi | 5,290psi | +80% | 36.5MPa |
| Compression perpendicular | 270psi | 500psi | +85% | 3.40MPa |
| Side hardness | 360lbf | 490lbf | +36% | 2,180N |
| Work to maximum load | 5.60in-lbf/in³ | 7.50in-lbf/in³ | +34% | 51.7kJ/m³ |
| Modulus of elasticity | 1.25M psi | 1.57M psi | +26% | 10.8GPa |
| Impact bending | 22in. | 28in. | +27% | 711mm |
Wood Handbook Table 5-3b, Table 4-3. Data & method · Guides