Design values for visually graded Canadian dimension lumber in Canada
The specified strengths and modulus of elasticity of visually graded dimension lumber are based on lumber that is graded in accordance with NLGA Standard Grading Rules for Canadian Lumber. All grades, except economy grade, are stress graded, that is, fifth percentile specified strengths are assigned to the different engineering properties such as tensile strength parallel to grain, compression strength perpendicular to grain, longitudinal shear strength, etc. The fifth percentile specified strengths and modulus of elasticity values are listed in the CSA O86 Engineering design in wood standard.
The design values are intended to be used by qualified designers and can be used in conjunction with the appropriate adjustment factors found in the CSA O86 standard. Design tables, examples and background information can be found in the CWC’s Wood Design Manual, which includes a copy of the CSA O86 standard, along with additional background information within the CSA O86 commentary.
For more information or to purchase standards from CSA Group, please visit http://shop.csa.ca/ or call 1-800-463-6727.