Balsam fir
Abies balsamea
Balsam fir measures 380 lbf on the Janka scale, about 29% as hard as northern red oak.
- Of the 155 woods, only seven are softer, seven stiffer for their weight and nine lighter.
- Of the seven true firs in the handbook, none shrinks less across the face.
U.S. hardwoodsU.S. softwoodsImported woodsNorthern red oak
Six measures
Balsam firU.S. softwoods medianOther woods
Janka hardness
380 lbf1,690 N8th softest of 15531st of 37 U.S. softwoods240 lbf3,680 lbfDensity
0.330.35 at 12% MC10th lightest of 1550.250.96Cupping tendency
2.3811th highest of 15528% above the U.S. softwoods median1.092.90Bending strength
9,200 psi63.4 MPa25th weakest of 1554,300 psi29,900 psiShrinkage across the face
6.9%radial 2.9%42nd lowest of 1553.5%12.7%Stiffness
1.45 M psi10.0 GPa43rd most flexible of 1550.54 M psi4.06 M psi
For its weight: stiffness-to-weight 4.39 (8th of 155).
How much it moves
Most of its movement runs along the rings (T/R 2.38): quartersawn, the same board would lose 0.17 in. instead of 0.41 in.
0.41 in.
off a 6-inch flatsawn board, green to oven-dry
- Tangential
- 6.9%
- Radial
- 2.9%
- Volume
- 11.2%
- T/R ratio
- 2.38 (145th most stable of 155)
End view, shrinkage drawn 3× life size.
Closest substitutes
- Subalpine fir
8% softer · 6% lighter · shrinks 0.5 points more across the face
- White fir
26% harder · 12% heavier · shrinks 0.1 points more across the face
- Grand fir
29% harder · 6% heavier · shrinks 0.6 points more across the face
Among the true firs
6th hardest of 7, lbf.
Laboratory values
Its most unusual laboratory figure is tension across the grain: the lowest of the 73 woods with a published value.
| Property | Green | Dry, 12% MC | Change when dried | Metric, 12% MC |
|---|---|---|---|---|
| Tension perpendicular | 180psi | 180psi | ±0% | 1.20MPa |
| Work to maximum load | 4.70in-lbf/in³ | 5.10in-lbf/in³ | +9% | 35.2kJ/m³ |
| Side hardness | 290lbf | 380lbf | +31% | 1,690N |
| Compression perpendicular | 190psi | 400psi | +111% | 2.80MPa |
| Shear parallel to grain | 660psi | 940psi | +42% | 6.50MPa |
| Impact bending | 16in. | 20in. | +25% | 508mm |
| Modulus of rupture | 5,500psi | 9,200psi | +67% | 63.4MPa |
| Compression parallel to grain | 2,630psi | 5,280psi | +101% | 36.4MPa |
| Modulus of elasticity | 1.25M psi | 1.45M psi | +16% | 10GPa |
Wood Handbook Table 5-3b, Table 4-3. Data & method · Guides