Taxonomy of Wood Products Engineered Wood Products

Wood Products Taxonomy Solid Wood Softwood Lumber Boards Dimension Lumber Timber Machine Stress Rated Glued Wood Finger Joined Edge Glued Treated Hardwood Composites Panels Particleboard Medium Density Fibreboard Plywood Oriented Strandboard Engineered Lumber Composites Glue Laminated Timber Laminated Veneer Lumber Oriented Strand Lumber Wood Products Taxonomy Engineered Wood Products I - Beams Cross Laminated Timber

Solid wood products Engineered wood products

Choice of Wood Products Product composition ? (a) one large piece of solid wood or (b) smaller pieces wood glued together Relative strength rating ? (a) 75-85 or (b) 50-100

Engineered wood products - benefits compared to solid wood More reliable Higher strength ratings Larger dimensions possible Smaller trees can be utilized

Variability in wood products frequency Solid wood strength

Variability in wood products mean lower 5th percentile Solid wood ÷ safety factors frequency strength allowable design stress

Variability in wood products mean mean lower 5th percentile ÷ safety factors Solid wood lower 5th percentile frequency Wood composite A ÷ safety factors strength allowable design stress allowable design stress

Variability in wood products mean mean lower 5th percentile Solid wood ÷ safety factors Wood composite B lower 5th percentile frequency ÷ safety factors strength allowable design stress allowable design stress

Solid wood vs. Engineered lumber composite frequency Which is “stronger”? Wood composite Solid wood strength “Stronger” = “Can accept higher design loads”

Reduction of natural variability Elements combined into more consistent engineered products Initial source of solid wood Strategic placement of elements Wood source reduced to designed elements

Wood Elements Veneer sheets Strands Veneer strips Lamstock

Wood Products Taxonomy Solid Wood Softwood Lumber Boards Dimension Lumber Timber Machine Stress Rated Glued Wood Finger Joined Edge Glued Treated Hardwood Composites Panels Particleboard Medium Density Fibreboard Plywood Oriented Strandboard Engineered Lumber Composites Glue Laminated Timber Laminated Veneer Lumber Oriented Strand Lumber Wood Products Taxonomy Engineered Wood Products I - Beams Cross Laminated Timber

Laminated Veneer Lumber Elements: Sheets of wooden veneer (1/8-1/10” thick, 2’ wide, 8’ long) Product Width 1½ - 3½ inches Dimensions: Depth up to 24 inches Length up to 80 feet Applications: Beams, headers, I-beam flange

LVL – manufacturing overview 2 1 4 3 5 6

Laminated Veneer Lumber (LVL) Edge Flat Softwood veneers produced as in plywood production Veneers graded prior to assembly Higher quality veneers are placed on the outsides Veneers glued with grain running parallel to each other  LVL used on flat (I-beam flanges) or on edge (beams, headers)

LVL – end use dimensions Width 1 ½ in., 1 ¾ in., and 3 ½ in. Depth up to 24 in. Length up to 24m

Reduction of natural variability Solid wood Variability is at its greatest level. Laminated Veneer Lumber Variability is reduced in one plane. Defects in veneer can be removed or dispersed Variability is reduced Yield of veneer from logs is higher than yield of solid lumber

Laminated Veneer Lumber LVL in I-beam LVL beam

LVL - headers

Glue Laminated Timber (Glulam) Elements: “Lamstock”, high quality dimension lumber (1½” thick, up to 10” wide, up to 20’ long) Product Width 3½-14 inches Dimensions: Depth up to 8 feet Length up to 140 feet Applications: Beams, columns, arches, trusses

Centre for Advanced Wood Processing

Glulam - laminations Top and bottom laminations might be different species Finger joints along laminations Total dimensions = 5.25” x 17.5” (This is not a commercial sample)

Glulam – build up of column Mulitple pieces per width of lamination Multiple laminations

Glue Laminated Lumber (Glulam) Individual lamstock elements are stress-rated prior to beam fabrication Stiffer elements are placed in more critical locations in member Very large dimensions possible

Glue Laminated Lumber (Glulam) Curved members can be created Tighter curves require thinner laminations Architectural as well as structural

Glulam - Columns, Beams and Rafters

Glulam - Roof Beams

Glulam - Curved Roof Beams

Glulam - Curved Bridges

Glulam – curved members