Wood species
Cypress wood
Cypress is a softwood (Taxodium distichum). At 12% moisture content it has a Janka hardness of 510 lbf (2,269 N) and it weighs about 32 lb/ft³ (515 kg/m³), 2.7 lb (1.22 kg) per board foot.
Also called: baldcypress, bald cypress, red cypress, pecky cypress.
Key numbers
- Janka hardness, 12% MC
- 510 lbf (2,269 N)
- Green: 390 lbf (1,735 N)
- Weight at 12% MC
- 32 lb/ft³ (515 kg/m³)
- 2.7 lb per board foot
- Specific gravity (oven-dry weight)
- 0.46 at 12% MC volume
- 0.42 on green volume
- Shrinkage, green to oven-dry
- Not measured tangential
One source: USDA Forest Products Laboratory, the authority for species properties it measured
Why: Measured by the USDA Forest Products Laboratory; cypress's density is worked from its specific gravity with the Handbook's own equation.
How much cypress moves
The 2021 Wood Handbook prints no shrinkage or movement coefficient for baldcypress, so this page gives no movement figure rather than borrow one from another species.
Color, grain and working
- Color
- Heartwood from light yellowish brown to dark brownish red, brown or chocolate; narrow, nearly white sapwood.
- Grain and texture
- Some trees have pockets of fungal decay (“pecky cypress”), which stops once the lumber is cut and dried.
- Working and character
- Moderately heavy, strong and hard. Old-growth heartwood is among the most decay-resistant US woods; second growth is only moderately resistant.
- Uses
- Siding, millwork and paneling; pecky cypress for decorative paneling.
The 2021 Handbook prints no shrinkage or movement coefficient for baldcypress, so this page gives no movement figures.
Adapted in our own words from the Wood Handbook, Chapter 2, p. 2-11.
Strength
Bending strength is the modulus of rupture (MOR); stiffness is the modulus of elasticity (MOE). Clear, straight-grained samples of baldcypress 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) | 6,600 psi (46 MPa) | 10,600 psi (73 MPa) |
| Stiffness (MOE) | 1,180,000 psi (8.1 GPa) | 1,440,000 psi (9.9 GPa) |
| Crushing strength (compression parallel to grain) | 3,580 psi (25 MPa) | 6,360 psi (44 MPa) |
| Compression perpendicular to grain | 400 psi (3 MPa) | 730 psi (5 MPa) |
| Shear parallel to grain | 810 psi (6 MPa) | 1,000 psi (7 MPa) |
| Tension perpendicular to grain | 300 psi (2 MPa) | 270 psi (2 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 baldcypress at 510 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 × 0.46 × 1.12.
Arithmetic: exact by definition , sources [1]
The number
About 32 lb/ft³, or 2.7 lb per board foot (1/12 ft³), at 12% moisture content.
Arithmetic: exact by definition
Sources