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Sizes and Species
D.Fir-L and Hem-Fir are the species groups most readily available in timber sizes, but S-P-F and Northern species may also be obtained. The Sizer database includes timbers up to 394 x 394mm (16" x 16".) in size; however availability of large sizes should be checked before specifying. Timbers may be obtained in lengths up to 9.1m (30 ft.), but this should also be confirmed with local suppliers.
Grades
The most readily available grades are No. 1 and No. 2; however, Select Structural may be ordered. Materials available from lumber yard stock are usually re-sawn to order from large timbers and should be re-graded after cutting. Verification of the grade may be obtained in writing from the supplier, or a qualified grading agency may be retained to check the supplied material.
Checking
Timbers are always dressed green since their large size makes kiln-drying impractical. As a result, some amount of shrinkage and checking can be expected after dressing. These effects are taken into account in the specified strengths.