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The decreasing supply of large diameter, old-growth trees resulted in the increased popularity of engineered wood products -- those made from young, small diameter trees and scrap wood that is reassembled into I-joists, boards and beams. But did you know that the engineered wood that is well-recognized in residential construction as header and girder material and I-joist chords, can also be used for wall framing with similar effective results?
Engineered wood is made from quick growing, abundant species such as aspen, fir, pine and poplar that are processed into wood veneers or strands, coated with adhesive, compressed into large billets, dried, then sawn into standard lumber dimensions. Often, the process of engineering the performance characteristics of the wood includes orienting the veneers or strands to maximize the member’s strength. Laminated veneer lumber (LVL), laminated strand lumber (LSL) and parallel strand lumber (PSL), are some of the types of engineered wood products. In walls, engineered wood can be used as a replacement for 2 x 4 and 2 x 6 dimensional lumber, installed with the same process, tools, and fasteners. Because engineered wood products are superior in strength, stability, and uniformity to standard lumber species of the U. S., headers and girders can be engineered for greater clear spans or to carry greater loads. This means that taller walls can be designed for greater environmental conditions (like high wind speed or seismic activity) at greater spacing (for windows and doors). This greater design flexibility, reduced waste (no culling), and the material’s dimensional stability drive the value decision.
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Engineered wood makes use of fast-growing small trees, and scrap wood.
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Engineered wood is uniform and stable.
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Engineered wood wall studs and plates are available in the United States through regional and local lumber distributors. Products are installed using the same tools and fasteners as dimensional lumber, so carpenters have adapted easily to their use.
Engineered wood generally is more price stable than dimensional lumber. Costs tend to range between three and four times that of dimensional lumber.
Not Applicable
Engineered wood products will have an approved evaluation report that can be submitted with the architectural plans for building permit review. Manufacturers supply load tables for their products to facilitate proper specification and installation.
Not Applicable
Engineered wood can be a substituted for dimensional lumber in a piece for piece replacement, or because of its greater load capacity, value engineered to fit the application. Studs are cut, handled, and assembled in the same manner as dimensional lumber.
Companies warrant the material to be free from manufacturing defects.
Some manufacturers offer a warranty for the adequacy of product design for the life expectancy of the building, provided it has been installed and used properly.
Because it is a composite of small pieces of wood and adhesive, engineered wood is consistent, dimensionally stable, and defect free. Products have greater strength characteristics than comparably-sized dimensional lumber of common species, like SPF. Engineered wood production utilizes small, fast-growing tree species which conserves natural resources. Engineered lumber will cost more than dimensional lumber because of its greater load-carrying capacity. As with untreated dimensional lumber, engineered wood applications are limited to areas that are not exposed to the elements.
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