Tempered hardboard, an engineered wood product, is made from wood fibers that have been tightly compressed together to form a solid sheet of building material. It is frequently referred to as Masonite® because it was invented by William H. Mason and originally manufactured by the Masonite Corporation. Tempered hardboard is similar to other types of fiberboard, but is usually more dense and water-resistant. This product is widely used in the construction of furniture and cabinets. It is typically manufactured in sheets that have a smooth finish on two sides and known as S2S panels. This type of hardboard is known for being both rigid and flexible at the same time.
Masonite® or tempered hardboard is manufactured by taking wood fibers coated with linseed oil and pressing them into sheet form at high temperatures. The linseed oil is added to the wood fibers to help bond them together during the manufacturing process. Unlike ordinary particleboard, hardboard products typically require no additional bonding materials in order to maintain their shape and strength. The use of linseed oil in the manufacturing process usually makes the hardboard unsuitable for painting. Tempered hardboard sheets are typically sturdier and more water-resistant than standard hardboard products.
This engineered wood product was first developed in the 1920s, and has been used for many decades as an exterior siding material for buildings and homes. The unique manufacturing process of this type of hardboard typically produces a strong, smooth sheet of construction material that is able to bend without cracking, splitting, or breaking. Although it is a very dense material, this kind of hardboard can usually be cut using common woodworking tools. Due to its flexibility, however, tempered hardboard should never be used in any type of structural application. It is typically sold in 4 feet (1.2192 meters) by 8 feet (2.4384 meters) sheets in a variety of thicknesses.
The material is also available as a prefinished product with veneers such as wood grain, Formica®, and various types of laminates including vinyl and paper. Finished hardboard panels are often used in bathrooms and kitchens because of their durability and waterproof qualities. Unfinished hardboard panels are typically used as cabinet backing and drawer bottoms. Tempered hardboard is also used for skateboard and bicycle stunt ramps because of its high degree of flexibility. It is also manufactured in a perforated form for use in certain types of commercial pegboard applications.