The past fifty years have seen unprecedented changes in technology and environmental stewardship impacting on construction. In response to these evolving issues, the homebuilding industry has modified its practices and use of materials. Correspondingly, environmental limitations and consumer demand have spurred a transition to engineered lightweight wood construction.
The wood products industry has also had to adapt, as fewer large trees are available for manufacturing. By developing ways to use smaller diameter trees to manufacture new, lighter weight structural products, the industry uses fewer resources — more efficiently, with less waste. In addition, these new products meet builder demand for deep, long, and straight structural building materials.
Engineered wood products can be defined as products consisting of a combination of smaller components to make a structural product, designed using engineering methods. They are an alternative to traditional sawn lumber.
To use as much fiber as possible from available logs, the logs are “stranded” (sliced into 1-inch to 12-inch strands), peeled (sliced off of a log like paper towels from a roll), or sawn. Then, the resulting pieces are combined with adhesives into a new engineered wood product.
Rigorous Code Acceptance
New products must meet strict standards set by the model building codes and evaluation services. Accredited certification agencies closely monitor the manufacturing process for quality control. Both the manufacturer and certification agencies test the product. I-joists, for example, are regularly and rigorously tested for strength and serviceability.
Products in the Market
Some examples of engineered wood products are: I-joists, trusses, glued-laminated timber (glulam), cross-laminated timber (CLT), and Structural Composite Lumber (SCL) that includes laminated veneer lumber (LVL), parallel strand lumber (PSL), and laminated strand lumber (LSL).