Taxonomy of Wood Products Solid Wood Products

Taxonomy of Wood ProductsSolid Wood Products

Secondary Wood Products WOOD Furniture Composites Solid Wood Pulp and Paper Panels Cabinets Engineered Lumber Composites Softwood Lumber Glued Treated Hardwood Pulp Paper Windows & Doors Wood/Non-wood Wood Based LVL Boards Finger joined Mechanical Millwork & Factory-built Housing Wood/Cement Particleboard OSL Dimension Edge glued Chemical Wood/Plastic MDF Glulam Timber Plywood MSR OSB Wood Products Taxonomy Engineered Wood Products I-Beams Trusses CLT

Dimension Lumber • “2 by 4”, “2 by 6”, “2 by 8” construction lumber •  Majority of lumber produced in North America •  Production grew approx. 1.4% p.a. from 1985-2005 • Bulk commodity product with little specialization • Used mainly in residential construction

Dimension lumber - sizes 4.0” 3.7” 3.5” 2.0” 1.5” 1.7” Rough sawn After drying After planing(“nominal” size) (actual size) “Two by four”

Dimension Lumber - sizes • Thickness – increments of 2 inches • Width – increments of 2 inches • Length – increments of 2 feet Softwood lumber pricing (US$/MBF) Premiums for larger cross-section dimensions and lengths.

Dimension Lumber

Dimension Lumber • Majority of production sold in US • SPF species group (Spruce - Pine – Fir)

Softwood Boards BC Wood Specialties •  Non-structural, finished product • 1” thick material, 2” width increments, 2’ length increments •  Markets are: export, industrial, home centres

Softwood boards Canadian softwood board species Wall panelling

Softwood boards Furniture Decorative panelling

Timber • Minimum dimensions 5.5” • High value product • Majority goes to export markets •  Production is decreasing

Timber • Post and beam construction • Architectural value as well as structural role • Higher value product than smaller dimensions ($/m3)

Timber Danzaland, Flickr 100_9859, CC BY-NC-ND 2.0 http://www.flickr.com/photos/monahan/3083747492/

Solid softwood lumber – species BoardsDimension lumberTimberSpruce SPF Douglas-firDouglas-fir Douglas-fir HemlockPines Hemlock HemlockCedars

Machine Stress Rated Lumber • Lumber is graded by machine rather than manually • Uses non-destructive measurement of stiffness to predict strength of lumber pieces •  Structural end-uses •  Value-added lumber product •  Trusses are large market

Bending test Maximum load Modulus of Rupture MOR“strength” Load Linear portion of curve Modulus of Elasticity MOE“stiffness” Deflection

MOE – MOR relationship MOR predicted x x x x x x x x x x x x x x MOR “strength” x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x MOE measured x x x x x MOE “stiffness”

Machine Stress Rated Lumber Sensor Rollers Load cell Lumber

MSR lumber in roof trusses

Short lengths Longer lengths e.g. dimension lumber trim ends

Removal of defects defect, e.g. knots Butt joint (end grain)

Finger Joined Lumber • Longer lengths produced from shorter stock • Allow defects to be reduced • End-to-end joints via side-grain gluing

Finger Jointed Lumber www.ufpi.com BC Wood Specialties •  Structural or non-structural joints can be made • Longer fingers → greater strengths • Increased dimensional stability in resulting piece •  Utilized in lumber, glulam, I-beams

Finger joints Narrower edge Wider face

Dimensional stability of finger joined lumber Warping tendency of any one piece is randomized in its location in finger-joined lumber and resulting piece is more dimensionally stable.

Edge-glued Panels  Edge-lamination of wood  Greater widths from narrow material  Dimensionally stable-panel produced  Industrial and finished retail products

Wood dryng defects T • Tangential shrinkage > Radial shrinkage • Natural tendency to “cup” • Cupping is greater in wider pieces of wood R R T

Dimensional stability of edge-glued panels Randomization of end grain patterns Less likely to cup

Edge-glued panels

Treated Wood • Preserves the wood against fungal degradation • For wood used in external conditions • Effectively poisons the wood • Chemical agent is either water-borne or oil-borne • Usually introduced into wood using pressure treatment

Treated WoodExamples of preservatives • Creosote • Pentachlorophenol (PCP) • Chromated copper arsenate (CCA) • Ammoniacal copper quaternary (ACQ)

Treated WoodPressure treatment vessels

Treated WoodExamples of preservative use Creosote Pentachlorophenol (PCP)

Treated WoodExamples of preservative use CCA ACQ

Pressure-treated Wood Non-incised lumber Incised lumber The retention of wood preservatives in wood species which do not readily abosrb the preservative chemical can be enhanced by incising the wood.

Hardwood Lumber • Visual appearance of lumber is key • Used for decorative and architectural purposes rather than structural products • Flooring, trim & molding, joinery, cabinets, furniture

Hardwood Lumber

Hardwood Lumber Grading system based on cutting high quality boards from rough lumber. • Thickness – usually 1 inch (but also other thicknesses) • Width – random widths • Length – increments of 1 foot

Lumber GradingSoftwood vs. Harwoods

Lumber Grading - softwoods • Softwood grading considers that the piece of lumber will be used as it stands and will not undergo subsequent reprocessing. • Therefore the greatest defect in the piece decides the grade of that piece of lumber.

Lumber Grading - harwoods • Hardwood boards are graded on the amount of clear (defect-free) wood that can be obtained after the removal of defects. • The boards are either “ripped” along the grain, or “chopped” across the grain to produce smaller, clear pieces are called “cuttings”. • Cuttings are then used in the production of other items such as edge-glued panels or furniture.

Solid softwood lumber Dimension Lumber Timber Boards Machine Stress Rated Lumber

Other solid lumber products Edge-glued Panels Finger Jointed lumber Treated Wood Hardwood

Taxonomy of Wood Products Solid Wood Products