For this reason, you should contact your building official well in advance of starting to construct your building. In Ontario, commercial lumber is graded by the sawmill that produces it. Under ideal conditions, where there are facilities and enough help to move the lumber, a grader can process approximately 20-30,000 board feet of lumber per day. Few farmers would have this quantity of lumber to grade at one time. Regardless of the care taken by farmers and small sawmills, some lumber may not be structurally adequate for the increasing size and complexity of farm structures.
Training is required to recognize the differences between species and grades of lumber.
In order to design structural components, an engineer needs to know the grade of lumber before a size can be determined. The OLMA and the CLA offer five-day courses for visual grading of softwood lumber. The Ontario Ministry of Municipal Affairs and Housing, administers the Ontario Building Code. In Ontario, the use of ungraded lumber in farm building projects is an accepted practice. The Ontario Building Code allows an owner to use ungraded lumber for posts, common rafters, lintels, beams and wall studs.