North America- Lumber Grades and Sizes
Lumber is graded for different applications and usage. Canadian and American mills grade their lumber which are certified by respective govt policies and procedures.
How it looks: Applications where look and display is important – durability, grain, colour and amount of clear lumber plays important role. For Example, grains of Douglas Fir, Hemlock are world famous and these woods can be stained, polished and varnished in any colour and style. For lighter shades, many prefer SPF wood.
Structural Usage:Constructions limber is graded for weight bearing purposes. All Europe and North American construction stands on constructional lumber. Lumber is graded and used according to application.
Grading system:Grades take into account the size, location of defects, and the suitability of the piece of lumber. The purpose of the grading system is to provide clear understanding to buyer and seller “ Quality “ of product being sold and purchased.
Moisture content of structural lumber: Structural lumber is dried to various levels, some applications use very less content of moisture while some applications prefer to have around 19% moisture level as it may be exposed to weather factors.
Moisture content For Indoor Applications: Lumber being used in making of Doors, Windows, Furniture, Flooring, Roofing, comes dried to a lower moisture content (avg. 10-14 percent).
Lumber Options from Canada : Canada have huge forest cover where sustainable forestry is being done. Canadian Douglas Fir, Hemlock, Cedar, SPF are famous species which are heavily used domestically as well as is basis of exports to various countries.
Want to read more ? Click here for Govt of Canada detailed information about Softwood Grading System: