Lumber is a general term which includes boards, dimension lumber, and timber. The product is manufactured by sawing logs into rough size lumber or cants (square timbers) which are edged, resawn to final dimension and cut to length.

This section deals with lumber products used for structural framing. In the context of North American construction materials, it usually refers to wood originating from softwood species of trees. In the smaller sizes it is known as “dimension lumber” and in the larger sizes as “timbers”.

Canadian lumber is economical, easy to procure, easy to adjust in the field, and has a dependability based on North American applied grading rules.

Visually Graded Dimension Lumber

Lumber has traditionally been graded by visual inspection. The grade of a given piece of lumber is based on visual observation of such characteristics as slope of grain and location of knots.

Machine Graded Dimension Lumber

A second grading system, using machines to sort the lumber into grades, has been in use for over 40 years. One of these lumber products, machine-stress rated [MSR] lumber, has been used for many years in highly demanding engineered applications.

Finger-joined Lumber

Finger-joined products are manufactured by taking shorter pieces of quality kiln-dried lumber, machining a “finger” profile in each end of the short-length pieces, adding an appropriate structural adhesive, and squeezing the pieces together to make a longer piece of lumber.


The general term “decking” is used to describe both tongue and groove lumber laid flat (plank decking), and lumber laid on edge (laminated decking).


The term “timber” describes lumber which is 140mm (5-1/2″) or more in its smallest dimension.