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Softwood and Hardwood - Structural Strength Classes

Strength classes, bending stress and mean density of hardwood and softwood

Structural timer is classified according the EU-code in different strength grades - where

  • D-Classes - refer to Deciduous Tree Species
  • C-Classes - refer to Coniferous Tree Species

Strength classes and structural softwoods and hardwoods physical properties:

Softwood and Hardwood - Structural Strength and Density vs. Classes
Strength ClassCharacteristic Minimum Bending Strength
- σ -

Typical Density
- ρ -

C14 14 350
C16 16 370
C18 18 380
C20 20 390
C22 22 410
C24 24 420
C27 27 450
C30 30 460
C35 35 480
C40 40 500
C45 45 520
C50 50 550
D30 30 640
D35 35 670
D40 40 700
D50 50 780
D60 60 840
D70 70 1080
  • 1 MPa = 106 Pa
  • BS EN 338

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