When architects and engineers look for the best in structural lumber, their first choice repeatedly is Douglas Fir.
It is dimensionally stable and universally recognized for its superior strength-to-weight ratio. Its high specific gravity provides excellent nail and plate-holding ability.
The species also enjoys a documented superior performance against strong forces resulting from natural phenomena such as winds, storms and earthquakes.
It is truly the ideal structural and general purpose wood for framing lumber in residential, light commercial, multi-story and industrial construction.
The Douglas Fir/Western Larch species combination has the highest modulus of elasticity (E or MOE) of the North American softwood species. This is the ratio of the amount a piece of lumber will deflect in proportion to an applied load; it is a reflection of the species’ high degree of stiffness, an important consideration in the design of floors and other systems.
In strength properties, Douglas Fir/Western Larch has the highest ratings of any western softwood for extreme fiber stress in bending (Fb); for tension parallel-to-grain (Ft); for horizontal sheer (Fv); for compression perpendicular-to-grain (Fc); and for compression parallel-to-grain (Fc//).
These physical working properties, as well as to the moderate durability of its heartwood and its excellent dimensional stability, provide the reasons many builders use Douglas Fir as the standard against which all other framing lumber is judged. It is also tight-knotted and close-grained, adding the bonus of beauty to its structural capabilities.
The straight grained and exceptionally strong Douglas Fir tree is one of the most dominant species in the Northwest forests.
After a forest fire, the tree springs to life, growing thickly in the sunshine of a newly open area.
Its stiffness and durability make it ideal for structural applications.
It also makes a good flooring and paneling product as well as a fine trim for doors and windows.
Douglas Fir is known for its distinctive grain patterns, produced by the varying degrees of spring and summer wood in the grain.
The color differences between the two range from yellowish to reddish brown. Douglas Fir flooring ages to a warm orange-brown color.
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