Taxonomy of Wood Products
Engineered Wood Products
Wood Products Taxonomy
WOOD
Composites
Engineered
Lumber
Composites
Panels
Wood/Nonwood
Solid Wood
Wood Based
Softwood
Lumber
Glued
Pulp and Paper
Treated
Hardwood
Pulp
Paper
LVL
Boards
Finger joined
Mechanical
Edge glued
Chemical
Wood/Cement
Particleboard
OSL
Dimension
Wood/Plastic
MDF
Glulam
Timber
Engineered Wood
Products
Plywood
MSR
I-Beams
Secondary
Wood Products
OSB
Furniture
Trusses
Cabinets
CLT
Windows & Doors
Millwork & Factory-built
Housing
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
4
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
6
Variability in wood products
mean
lower 5th percentile
frequency
Solid wood
÷ safety factors
allowable design stress
strength
7
Variability in wood products
mean
mean
lower 5th percentile
÷ safety factors
Solid wood
lower 5th percentile
frequency
Wood composite A
÷ safety factors
allowable design stress
allowable design stress
strength
8
Variability in wood products
mean
mean
lower 5th percentile
Solid wood
÷ safety factors
Wood composite B
lower 5th percentile
frequency
÷ safety factors
allowable design stress
allowable design stress
strength
9
Solid wood vs. Engineered lumber composite
frequency
Which is “stronger”?
Wood composite
Solid wood
strength
“Stronger” = “Can accept higher design loads”
10
Reduction of natural variability
Elements combined
into more consistent
engineered products
Initial source of
solid wood
Wood source
reduced to
designed
elements
Strategic
placement
of elements
11
Wood Elements
Veneer sheets
Strands
Veneer strips
Lamstock
Wood Products Taxonomy
WOOD
Composites
Engineered
Lumber
Composites
Panels
Wood/Nonwood
Solid Wood
Wood Based
Softwood
Lumber
Glued
Pulp and Paper
Treated
Hardwood
Pulp
Paper
LVL
Boards
Finger joined
Mechanical
Edge glued
Chemical
Wood/Cement
Particleboard
OSL
Dimension
Wood/Plastic
MDF
Glulam
Timber
Engineered Wood
Products
Plywood
MSR
Secondary
Wood Products
OSB
I-Beams
Furniture
Trusses
Cabinets
Windows & Doors
Millwork & Factory-built
Housing
Laminated Veneer Lumber
Elements:
Sheets of wooden veneer
(1/8-1/10” thick, 2’ wide, 8’ long)
Product
Width
Dimensions: Depth
Length
1½ - 3½ inches
up to 24 inches
up to 80 feet
Applications: Beams, headers, I-beam flange
14
LVL – manufacturing overview
2
1
4
5
6
3
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,
16
headers)
LVL – end use dimensions
• Width
• Depth
• Length
1 ½ in., 1 ¾ in., and 3 ½ in.
up to 24 in.
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
18
Laminated Veneer Lumber
LVL beam
LVL in I-beam
19
LVL - headers
Glue Laminated Timber (Glulam)
Finger joint
Individual
laminations
Elements:
“Lamstock”, high quality dimension lumber
(1½” thick, up to 10” wide, up to 20’ long)
Product
Width
Dimensions: Depth
Length
3½-14 inches
up to 8 feet
up to 140 feet
Applications: Beams, columns, arches, trusses
21
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
Multiple
laminations
Mulitple
pieces per
width of
lamination
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
25
Glue Laminated Lumber (Glulam)
 Curved members can be created
 Tighter curves require thinner laminations
 Architectural as well as structural
26
Glulam - Columns, Beams and Rafters
27
Glulam - Roof Beams
28
Glulam - Curved Roof Beams
29
Glulam - Curved Bridges
30
Glulam – curved members