1. Taxonomy of Wood Products Engineered Wood Products

2. 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

3. Solid wood products
Engineered wood products

4. Choice of Wood Products
Product composition ?
(a) one large piece of solid wood or (b) smaller pieces wood glued together
Relative strength rating ?
(a) or (b)

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

6. Variability in wood products
frequency
Solid wood
strength

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

8. 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

9. 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

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

11. 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

12. Wood Elements
Veneer sheets
Strands
Veneer strips
Lamstock

13. 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

14. 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

15. LVL – manufacturing overview2 1 4 3 5 6

16. 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)

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

18. 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

19. Laminated Veneer Lumber
LVL in I-beam
LVL beam

20. LVL - headers

21. 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

22. Centre for Advanced Wood Processing

23. 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)

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

25. 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

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

27. Glulam - Columns, Beams and Rafters

28. Glulam - Roof Beams

29. Glulam - Curved Roof Beams

30. Glulam - Curved Bridges

31. Glulam – curved members