Modulus of Rupture (MOR) Strength Ratings for Various Species of Wood (psi)

The modulus of rupture reflects the maximum loadcarrying capacity of the species in bending strength and is proportional to the maximum strength or breaking point as borne by the specimen. (1)

  • Purpleheart 21,300 psi
  • Apitong, Keruing 19,900 psi
  • Brazilian Apitong, Angelim Pedra 18,255 psi
  • White Oak 15,200 psi
  • Red Oak 14,300 psi
  • Douglas Fir 12,400 psi
  • Western Red Cedar 7,500 psi

Modulus of Elasticity (MOE) Stiffness Ratings for Various Species of Wood (1000 psi)

The modulus of elasticity ratings as shown below are based on the stiffness or resistance to bending of the particular wood species. These ratings are for the common longitudinal modulus of elasticity not the radial or tangential ratings.(1)

  • Purpleheart 2,420 1000 psi
  • Apitong, Keruing 2,070 1000 psi
  • Brazilian Apitong, Angelim Pedra 2,050 1000 psi
  • Douglas Fir 1,950 1000 psi
  • Red Oak 1,850 1000 psi
  • White Oak 1,780 1000 psi
  • Western Red Cedar 1,110 1000 psi

Janka Hardness Ratings for Various Species of Wood (pounds)

Hardness is defined as resistance to indentation using a modified Janka hardness test, measured by the load required to embed a 11.28-mm (0.444-in.) ball to one-half its diameter. Values presented are the average of radial and tangential penetrations.(1)

  • Purpleheart 1,860 lbs
  • Brazilian Apitong, Angelim Pedra 1,720 lbs
  • Apitong, Keruing 1,520 lbs
  • White Oak 1,360 lbs
  • Red Oak 1,290 lbs
  • Douglas Fir 660 lbs
  • Western Red Cedar 350 lbs

Density Ratings for Various Species of Wood (KG per Cubic Meter)

The weight of a wood product is determined by the density of the basic wood structure and by the moisture content of the material. The density of the wood, exclusive of water, varies greatly both within and between species. Variations in density of approximately 10% within a particular species should be considered normal. Moisture makes up part of the weight of wood and should always be taken into consideration. The values below represent the density at approximately 12% moisture content.(1)

  • Purpleheart 1,057 KG/m3
  • Brazilian Apitong, Angelim Pedra 960 KG/m3
  • White Oak 900 KG/m3
  • Apitong, Keruing 790 KG/m3
  • Red Oak 780 KG/m3
  • Douglas Fir 530 KG/m3
  • Western Red Cedar 260 KG/m3

(1) The Wood Handbook - Wood as an engineering material, USDA, General Technical Report 113.