Wood species
Beech wood
Beech is a hardwood (Fagus grandifolia). At 12% moisture content it has a Janka hardness of 1,300 lbf (5,783 N) and it weighs about 45 lb/ft³ (717 kg/m³), 3.7 lb (1.69 kg) per board foot.
Also called: American beech.
Key numbers
- Janka hardness, 12% MC
- 1,300 lbf (5,783 N)
- Green: 850 lbf (3,781 N)
- Weight at 12% MC
- 45 lb/ft³ (717 kg/m³)
- 3.7 lb per board foot
- Specific gravity (oven-dry weight)
- 0.64 at 12% MC volume
- 0.56 on green volume
- Shrinkage, green to oven-dry
- 11.9% tangential
- Radial 5.5%, volumetric 17.2%
One source: USDA Forest Products Laboratory, the authority for species properties it measured
Why: Measured by the USDA Forest Products Laboratory; beech's density is worked from its specific gravity with the Handbook's own equation.
How much beech moves
A 12 in wide flatsawn board of American beech that goes from 6% to 12% moisture content swells about 0.31 in (about 5/16 in, 7.9 mm). Quartersawn, the same board moves about 0.14 in (about 1/8 in, 3.5 mm). Flatsawn faces move 2.2 times as much as quartersawn ones, because the wood shrinks 11.9% around the growth rings but only 5.5% across them.
Worked with the Wood Handbook's dimensional change coefficients for American beech (Table 13-5: 0.00431 tangential, 0.0019 radial per 1% change in moisture content), which hold between 6% and 14%. Individual boards vary: the Handbook gives shrinkage a coefficient of variation of about 15% (p. 4-11).
Color, grain and working
- Color
- Nearly white sapwood and reddish-brown heartwood, sometimes with no clear boundary between them.
- Grain and texture
- Close, uniform texture with little figure.
- Working and character
- Heavy, hard, strong and tough, and very good for steam bending. It shrinks a lot, so it needs careful drying, then machines smoothly and turns well.
- Uses
- Flooring, furniture, brush blocks, handles, veneer, wooden ware and containers.
Adapted in our own words from the Wood Handbook, Chapter 2, p. 2-5.
Strength
Bending strength is the modulus of rupture (MOR); stiffness is the modulus of elasticity (MOE). Clear, straight-grained samples of American beech tested by the Forest Products Laboratory (Wood Handbook Table 5-3b). Knots and cross grain make lumber weaker than these clear samples (Handbook Chapter 5).
| Property | Green | 12% MC |
|---|---|---|
| Bending strength (MOR) | 8,600 psi (59 MPa) | 14,900 psi (103 MPa) |
| Stiffness (MOE) | 1,380,000 psi (9.5 GPa) | 1,720,000 psi (11.9 GPa) |
| Crushing strength (compression parallel to grain) | 3,550 psi (24 MPa) | 7,300 psi (50 MPa) |
| Compression perpendicular to grain | 540 psi (4 MPa) | 1,010 psi (7 MPa) |
| Shear parallel to grain | 1,290 psi (9 MPa) | 2,010 psi (14 MPa) |
| Tension perpendicular to grain | 720 psi (5 MPa) | 1,010 psi (7 MPa) |
A dash means the Handbook prints no value; none is filled in.
Dust and health
- Wood dust is classed as carcinogenic to humans (Group 1) by the International Agency for Research on Cancer, chiefly for cancers of the nose and sinuses.
- NIOSH recommends keeping wood dust exposure to 1 mg/m³ of total dust, as quoted in OSHA's sawmill guidance.
This is what the named authorities publish, not medical advice.
Compare with
Why these numbers
Why these numbers?
The situation
The USDA Forest Products Laboratory measured American beech at 1,300 lbf of side hardness at 12% moisture content, on clear, straight-grained samples (Wood Handbook Table 5-3b).
One source: USDA Forest Products Laboratory, the authority for species properties it measured , sources [1]
What that means
Side hardness (Janka) is the load needed to press a 0.444 in (11.28 mm) steel ball halfway into the wood across the grain; a higher number dents less (Handbook p. 5-5).
One source: USDA Forest Products Laboratory, the authority for species properties it measured , sources [1]
So
Density at 12% is water's density × specific gravity × (1 + 0.12) (Handbook Eq. 4-14): 62.43 × 0.64 × 1.12.
Arithmetic: exact by definition , sources [1]
The number
About 45 lb/ft³, or 3.7 lb per board foot (1/12 ft³), at 12% moisture content.
Arithmetic: exact by definition
Sources