Plywood Turns 100

  
  Archaeologists have found traces of laminated wood in the tombs of Egyptian pharaoh's, dating the first engineered wood applications back thousands of years. In the early 1800's, the Chinese created primitive forms of plywood by gluing together shaved pieces of wood to create furniture. It wasn't until 1905 however that plywood was officially introduced by a small wooden box company in Portland, Ore. Shortly after, plywood was used to create several items, such as cabinets and doors - even running boards for automobiles.

A major breakthrough came in 1934 when the first waterproof adhesive made plywood suitable for outdoor applications, and as a result, it had a major impact during World War II. Among other things, it was used to build barracks and crating for machinery parts. The Navy built plywood PT boats and the Air Force flew reconnaissance missions in plywood gliders. Lifeboats on hundreds of ships were also made of plywood and helped keep supply lines open in the Atlantic and Pacific. Back in America, plywood had become a staple of the residential construction market and the post-war boom saw an even greater need. By 1975, mills in the U.S. were creating more than 16 billion square feet of plywood annually - or approximately enough to circle the globe 120 times if the pieces were laid end to end. At the time, the largest market for plywood was the industrial sector, which used it for items such as pallets, crates, shipping containers, furniture frames, and truck trailer linings. Today, plywood and more advanced forms of engineered wood are used in the construction of virtually every home built in North America.

What is Plywood?

Simply put, plywood is a form of engineered wood made of three or more layers of wood veneer laminated together with glue.

"Plywood uses cross-laminated layers of wood to create an integral unit that is stronger and stiffer than the sum of its parts," said Lou Manfredini, a home builder and regular contributor to NBC's Today Show. "Plywood sheets can also be made in all sizes and thicknesses, making it extremely versatile in countless construction and industrial applications."

Plywood has been revolutionary because it created a relatively in-expensive, super-strong material that could be used for most any building application. Prior to its creation, most building materials such as steel and brick were heavy, expensive and not easy to customize.

"Plywood and other forms of engineered wood are designed for easier handling, faster construction and lower labor costs for builders," said Manfredini. "Using plywood also means that builders save money and prospective home buyers get their dream homes at a better price."

Further Advancements in Engineered Wood Technology

Since 1980, a newer type of engineered wood called Oriented Strand Board (OSB) has displaced some plywood use in residential construction, but home building still accounts for nearly one-third of the plywood market. Its primary uses are for wall and roof sheathing, siding, soffits and cabinets.

Newer forms of engineered wood continue to expand the strength and versatility of wood, creating new and unique building opportunities. In fact, wood has proven to have a solution to most building demands in the 21st century. Newer forms of engineered wood include:
  • Oriented Strand Board
    Oriented Strand Board (OSB) is often manufactured into low cost sheet siding materials that can be assembled quickly and easily for new homes. OSB is widely used in residential and commercial construction and is gaining popularity in markets such as materials handling and the manufacturing of upholstered furniture.
  • Parallel Strand Lumber
    A superior example of engineered lumber, Parallel Strand Lumber (PSL), is a high-strength composite prized by many contractors because it is not limited by length. PSL is made from long strands of wood laid next to each other lengthwise. The strands are glued together under tremendous pressure, forming large, extremely long blocks known as billets. The billets are then milled to size for use as beams and columns.
  • Prefabricated Wood I-Joists
    Also known as I-beams, wood I-joists are structural, load-carrying products designed for floor and roof support applications. Their "I" configuration makes it possible to create long pieces of wood that are strong and stiff but also relatively light in weight. I-joists are used extensively in residential construction and their rate of growth is among the highest of all engineered wood products.
  • Glued Laminated Lumber
    Also known as "Glulam", Glued Laminated Lumber is an engineered stress-rated product created by bonding individual pieces of lumber together that have a thickness of 50 mm (2 in.) or less. It can be easily shaped into forms ranging from straight beams to complex curved members and is used for a wide variety of structural applications in both residential and nonresidential construction.
During its 100 years of existence, plywood and its engineered wood successors have built a solid and storied foundation, revolutionizing how wood is used in the building industry. New products and innovations promise to continue wood's role as a superior building product by providing solutions to the most challenging demands of modern construction.