Tempo:
Table 7 Dimension lumber – grades and uses Common Grade Mix1
Sizes, mm (in.)
Grades
38 to 89 mm (2 to 4 in.) thick; 38 to 89 mm (2 to 4 in.) wide
Select structural No. 1 and No. 2
No. 2 and better (No. 2 & Btr.)
Most common; used in most construction. Shows high strength, stiffness and good appearance. Preferred for trusses, rafters and roof joists.
No. 33
—
Used in construction where high strength and appearance are not important, such as studs in non-loadbearing walls.
Construction3 Standard3
Standard and better (Std. & Btr.)
Most common, used in general framing work. Has less strength than No. 2 and better structural light framing, but is stronger and allows longer spans than No. 3.
Utility2
—
Used most economically where high strength is not important, such as studs and plates in partition walls, blocking and bracing.
Economy2
—
Used in temporary or low-cost construction where strength and appearance are not important.
Select Structural No. 1 and No. 2
No. 2 & Btr.
Most common; used in most construction where high strength and stiffness are desired such as floor joists, roof joists and rafters.
No. 33
—
Used in general construction where strength is not important.
Economy2
—
Used in temporary or low-cost construction where strength and appearance are not important.
Stud3
—
Most common; special purpose grade intended for all stud uses, including bearing walls
Economy stud2
—
Used in temporary or low-cost construction where strength and appearance are not important.
38 to 89 mm (2 to 4 in.) thick; 114 mm (5 in. ) and wider
38 to 89 mm (2 to 4 in.) thick; 38 mm (2 in.) and wider
Principal Uses
Grade Category Structural light framing
Light framing
Structural joists and planks
Stud
Notes to Table 7 1. For ease in grade sorting at the mill, the higher grades are combined and sold as a grade mix. Pieces of lumber in the grade mix are still individually grade stamped. 2. Except for the utility and economy grades, all grades are stress graded, which means specified strengths have been assigned and span tables calculated. 3. Construction, Standard, Stud and No. 3 Grades are typically used in designs that are not composed of 3 or more essentially parallel members spaced on 600 mm (24 in.) centres or less, so arranged or connected to mutually support loading.
Sizes, mm (in.)
Grades
38 to 89 mm (2 to 4 in.) thick; 38 to 89 mm (2 to 4 in.) wide
Select structural No. 1 and No. 2
No. 2 and better (No. 2 & Btr.)
Most common; used in most construction. Shows high strength, stiffness and good appearance. Preferred for trusses, rafters and roof joists.
No. 33
—
Used in construction where high strength and appearance are not important, such as studs in non-loadbearing walls.
Construction3 Standard3
Standard and better (Std. & Btr.)
Most common, used in general framing work. Has less strength than No. 2 and better structural light framing, but is stronger and allows longer spans than No. 3.
Utility2
—
Used most economically where high strength is not important, such as studs and plates in partition walls, blocking and bracing.
Economy2
—
Used in temporary or low-cost construction where strength and appearance are not important.
Select Structural No. 1 and No. 2
No. 2 & Btr.
Most common; used in most construction where high strength and stiffness are desired such as floor joists, roof joists and rafters.
No. 33
—
Used in general construction where strength is not important.
Economy2
—
Used in temporary or low-cost construction where strength and appearance are not important.
Stud3
—
Most common; special purpose grade intended for all stud uses, including bearing walls
Economy stud2
—
Used in temporary or low-cost construction where strength and appearance are not important.
38 to 89 mm (2 to 4 in.) thick; 114 mm (5 in. ) and wider
38 to 89 mm (2 to 4 in.) thick; 38 mm (2 in.) and wider
Principal Uses
Grade Category Structural light framing
Light framing
Structural joists and planks
Stud
Notes to Table 7 1. For ease in grade sorting at the mill, the higher grades are combined and sold as a grade mix. Pieces of lumber in the grade mix are still individually grade stamped. 2. Except for the utility and economy grades, all grades are stress graded, which means specified strengths have been assigned and span tables calculated. 3. Construction, Standard, Stud and No. 3 Grades are typically used in designs that are not composed of 3 or more essentially parallel members spaced on 600 mm (24 in.) centres or less, so arranged or connected to mutually support loading.
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