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Unit 7. Engineered Wood Products. Engineered Wood Panels • Plywood • Oriented Strand Board • Composite Panels • APA Performance Rated Panel Trademark • Nonstructural Panels • Engineered Lumber.
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Unit 7 Engineered Wood Products Engineered Wood Panels • Plywood • Oriented Strand Board • Composite Panels • APA Performance Rated Panel Trademark • Nonstructural Panels • Engineered Lumber
Engineered wood products, such as oriented strand board and wood I-joists, are commonly used for structural applications.
Performance rated panels include plywood, oriented strand board, and composite panels.
Strength and stiffness properties are affected by wood species.
Cross-lamination provides dimensional stability to plywood panels.
The manufacture of plywood begins with peeling veneer strips from peeler logs. The veneer strips are then cross-laminated to produce plywood panels.
Veneers of higher grade are used on the faces and backs of panels that will be exposed.
Medium density overlay plywood is used for siding and other exterior applications, and provides a smooth, toothed surface for a paint base.
Plyform is a performance rated plywood panel that provides a smooth and durable concrete-forming surface.
Fiberglass-reinforced-plastic plywood panels consist of fiber-reinforced overlays bonded to a plywood panel.
Oriented strand board is a structural wood panel commonly used for wall sheathing.
The manufacture of oriented strand board (OSB) begins with soaking and debarking logs before they are shredded. Wood strands up to 6″ long are formed into layers and cross-laminated to provide OSB with its strength and dimensional stability.
Composite panels have veneer faces with wood fiber crossbands and core.
Performance rated panels are identified by trademarks. Additional trademarks and descriptions are shown in the Appendix.
Hardwood plywood is commonly used for interior finish applications.
Hardwood plywood panel grades are based on natural growth characteristics, including color variations, burls, and pin knots, and the number of repairs in the panel face and back.
Medium density fiberboard is used for a variety of exterior and interior applications including siding. Note the spacer block being used to uniformly space the courses of siding.
Hardboard is a nonstructural panel product that has no grain pattern and has a uniform density, thickness, and appearance.
Particleboard is a nonstructural reconstituted panel consisting of particles that are bonded together using a synthetic resin or binder. A plastic laminate is applied to the particleboard for certain applications.
Glulam timbers are commonly used for beams in commercial and residential construction.
Laminated veneer lumber (LVL) is composed of layered veneers and waterproof adhesive and is commonly used for beams. Note the wood I-joists attached to the LVL beam.
Parallel strand lumber (PSL) is used for beams, headers, and load-bearing columns. PSL is used for the main beam and supporting column in this application.
Wood I-joists are composed of oriented strand board or plywood webs with dimension lumber or laminated veneer lumber flanges.
Rim boards tie together wood I-joists and fill the space between the top plate and bottom plate of two wall sections.
The ends of short pieces of lumber are milled to produce fingers. The short pieces are then attached to each other to form finger-jointed lumber, which is used for structural applications such as studs, plates, joists, and rafters.
Finger-jointed lumber is divided into two end-use applications. Finger-jointed lumber acceptable for all structural applications is stamped with “CERT. EXT. JNTS.” while finger-jointed lumber acceptable only for vertical applications is stamped with “VERTICAL USE ONLY” or “STUD USE ONLY.”