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Wood Utilization—Wood Industry in North America Wood Utilization—Wood Industry in North America

How much wood is used in building a house? For a 2000 ft 2 How much wood is used in building a house? For a 2000 ft 2 wood-framed house • 16, 2000 board ft. (1 bf = 1’ x 1”) Lumber or 1, 350 ft 3 or 20. 5 m 3 or 20 pine trees (30” DBH) • Plus 9, 500 ft 2 (based on 0. 5” thick) Structural Panels or 400 ft 3 or 300 4’ x 8’ x 0. 5” sheets of Plywood, OSB, or Hardboard for sheathing, decking & siding • Wood for decks and non-structural panels are extra

Lumber • Solid lumber is good but subjects to availability and variability in physical Lumber • Solid lumber is good but subjects to availability and variability in physical properties • Can be substitutes by engineered wood products, such as Parallel Strand L, I-joist, Laminated Veneer L and Laminated Strand L Plus Glue-laminated Timber Glulam PSL I-Joist LVL LSL

Advantages of Engineered Products • Value-added and conservative These products made from materials of Advantages of Engineered Products • Value-added and conservative These products made from materials of lower grades and processing residues • Predictable physical properties and performances

Disadvantages • Wood is good but needs to be protected from many enemies Fires Disadvantages • Wood is good but needs to be protected from many enemies Fires destroy houses And billions of dollars Property lose annually Along with 12, 200 fatalities

Enemies of Wood • Termites also destroy houses Annual property lose: 250 M$ Costs Enemies of Wood • Termites also destroy houses Annual property lose: 250 M$ Costs 125 M$/yr in Corrective measures.

Wood Decays Millions are spent annually to repair houses due to decay Bath room Wood Decays Millions are spent annually to repair houses due to decay Bath room leakage causes decay A brown-rot fungus is eating up the wood My Pella window decayed Only because of inproper installation!

The wood industry is proud to be environmentally friendly • A survey was conducted The wood industry is proud to be environmentally friendly • A survey was conducted in 1996 by the Forest Products Laboratory to identify Top Ten Most Significant Forest Products Technologies

Here They Are #1 Development of wood preservative treatments to extend the service life Here They Are #1 Development of wood preservative treatments to extend the service life of wood --How many trees saved? #2 Oriented Strand Board manufacturing --Use low-value species and milling residues

#3 Manufacturing paper from hardwood and wood wastes --Again, saving more valuable softwoods #4 #3 Manufacturing paper from hardwood and wood wastes --Again, saving more valuable softwoods #4 Technology for plywood production from Southern pine --Saved many big Douglas fir and larch trees

#5 Methods to utilize alternative/low-value species #6 Methods of processing small logs --Computer technologies #5 Methods to utilize alternative/low-value species #6 Methods of processing small logs --Computer technologies make it possible #7 Development of composite products from waste or low-value woods/fibers including hardboard, particleboard, medium density fiberboard, wood/plastic composites

#8 Development of recycling technologies for paper, wastewood and agricultural fibers #9 Development of #8 Development of recycling technologies for paper, wastewood and agricultural fibers #9 Development of non-toxic wood preservatives #10 Technology transfer to the forest products industry