Wood & Lumber Basics
Arch 330
Fall 2008

Look at Master Format2004
Division 06- Wood, Plastics and Composites
Maintenance
 Cleaning, Rehabilitation, Restoration, Preservation
Wood Treatment
 Fire-Retardant Wood Treatment
 Preservation Wood Treatment
 Eradication of Insects in Wood
 Antiseptic Treatment of wood
 Shop Applied Wood Coatings

Look at Master Format2004
Division 06- Wood, Plastics and Composites
Rough Carpentry
 Wood Framing
 Structural Panels
 Heavy Timber
 Treated Wood Foundations
 Wood Decking
 Sheathing
 Shop Fabricated Structural Wood (Manufactured Wood
Products)
 Glued-Laminated Construction

Look at Master Format2004
Division 06- Wood, Plastics and Composites
Finish Carpentry
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Millwork
Pre-finished Paneling
Architectural Woodwork
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Wood Casework
Wood Paneling
Wood Stairs and Railings
Ornamental Woodwork
Wood Trim
Wood Frames
Structural Plastics and Composites

Fire Retardant Treatment
 New Issues
Decay-Insect Resistance
 Pressure treated –preservatives (30)yrs.
Reduces disadvantages does not eliminate them

 Our own material lab- patents on several manufactured products
 SIPs-Structural Insulated Panels

Can decay, needs care with use, treating or coating
Is flammable –needs covering or treating in many uses especially in Engineered Wood
Products
Quality and availability have decreased
Poor insulation characteristics – need to coordinate with insulation

Rays

Wood & Lumber Basics
Trees are divided up into two broad categories:
 Hardwoods
 Softwoods
Please note:
This has nothing to do with the softness or hardness of the wood.
Balsa Wood is actually classified as a hardwood!

Wood & Lumber Basics
Better to divide wood into two broad categories: (I.e. Botany Terms)
- Thus -
 Hardwoods are Angiosperms
(apple)
 Seeds on the inside of the fruit and have a flower.
 With few exceptions they loose there leaves
 Softwoods are Gymnosperms
(Pinecone)
 Seeds are exposed usually in a cone.

Wood & Lumber Basics
Main Entry: an·gio·sperm
Pronunciation: 'an-jE-&-"sp&rm
Function: noun
Etymology: ultimately from New Latin angi+ Greek sperma seed -- more at SPERM
: any of a class (Angiospermae) or division
(Magnoliophyta) of vascular plants (as magnolias, grasses, oaks, roses, and daisies) that have the ovules and seeds enclosed in an ovary, form the embryo and endosperm by double fertilization, and typically have each flower surrounded by a perianth composed of two sets of floral envelopes comprising the calyx and corolla -- called also flowering plant
an·gio·sper·mous /"an-jE-&-'sp&r-m&s/ adjective

Main Entry: gym·no·sperm
Pronunciation: 'jim-n&-"sp&rm
Function: noun
Etymology: ultimately from Greek gymnos + sperma seed
-- more at SPERM
: any of a group of vascular plants that produce naked seeds not enclosed in an ovary, that were formerly considered a class (Gymnospermae) of seed plants, but that are now considered polyphyletic in origin and divided into several extinct divisions and four divisions with surviving members typified by the cycadophytes, conifers, ginkgo, and ephedras -- compare ANGIOSPERM

Wood & Lumber Basics
Moisture content of wood
 Living trees moisture as a percentage of wood substance can range from 30 to 200 percent.
 Water in trees exist as water or water vapor in the cell lumens (cavities) or “bound” within the cell walls.

Wood & Lumber Basics
Green wood –where the cell walls are completely saturated with water.
However
Green wood also contains additional water in the lumens
Thus the term Green wood would mean freshly cut trees dimensionally stable. As opposed to
“green” wood which is term used in grading lumber.

Wood & Lumber Basics
As we dry wood
 Water leaves the cell lumens (cavities).
 However the cell walls are still saturated
This is process where water remains in the cell walls but not in the cell lumens or cavities. This is referred to as the…..

Wood & Lumber Basics
“ Green ” condition of lumber is where the lumber is dried to a point below the fiber saturation point.
Equilibrium Moisture Content of lumber is where the lumber is dried to where the wood is neither gaining or losing moisture.
Once you reach equilibrium moisture content
(max. moisture content around 30%), the wood can not take on any more water than the 30%.

Wood & Lumber Basics
Orthotropic Nature of Wood
 Longitudinal (shrinks least)
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Tangential (shrinks most)
Radial (Shrinks ½ of tangential)
Thus wood is anisotropic material in that it does not shrink equally.
Anisotropic causes us the most difficulty in working with wood in combination as to how the wood is milled or cut.
Foot note: Least known by today's craftsperson.

(½ of tangential)
(Shrinks least)
( Shrinks most)

Anisotropic

Very important for finish work

Board Foot
 Standard measurement
 Based on Nominal Measurements
(Remember nominal are not actual measurements)
 Calculations
(thickness x width) /12” x Length X
Number of Pieces
Prices are quoted usually by the bf in thousand board feet or M i.e. $456.00 / Mbf =.456 bf

Structural:
 Heavy timber framing
 Light Framing
 Studs, Beams, Columns
 Standard Dimensions 2X4 2X6 etc
Manufactured Wood Products
 Glue-Laminated Beams
 Wood Trussed Rafters
 Exterior Cladding—plywood, sheathing, siding
 Engineered Wood Products

Wood plank and beam systems
A timber framed custom home
Concerns for the future
 Renewable Resources
 Old Growth Good
 Alternate Wood Products
 Our own material lab- patents on several manufactured products
 SIPs-Structural Insulated Panels

Wood products glued and manufactured:
 Better Strength
 Better Appearance—more dimensional stable
 More efficient use of wood products
 Can use smaller logs, wood not normally used for lumber

 Glue-Laminated Beams
 Wood Trussed Rafters
 Engineered Wood Products
 Exterior Cladding—plywood, sheathing, siding

Selected pieces of lumber glued together for stronger beam
No seasoning cracking
Variety of sizes—long lengths possible
Easy availability
Variety of grades – visual

Trusses can be custom fabricated
 Heavy timber or light dimensional lumber
Truss span large area without intermediate support
Types of trusses:
 Fan, scissors, Fink, Prat, etc.

Manufactured lumber
Laminated decking
Veneer: thin-cut pieces
Slicing of veneers:
 Rotary
 Plain
 Quarter

Exterior Applications-
 Sheathing: oriented strand (OSB)(waferboard) sheathing
 Siding
Interior Applications (particleboard)
 Underlayment
 Cabinets: Overlay finish

Layers of veneer adhered together by glue, heat, pressure
Outside plies are face plies or face and back
Various number of plies: 3, 5, 6
 Effect stability and quality
Structural Plywood:
 Stamped, waterproof, exterior use or interior protected
Veneer Grading: face and back: A,B,C,D-(Ex. CDX)

Structural Plywood
 Sheathing Roof, Wall, Floor- Exterior Glue
Exterior Use
 Siding, soffit
Cabinet Work
Finish Applications

Sub-floor
Underlayment
Wall Sheathing
Roofing
Box Beams

From fast-growing species such as aspen or yellow poplar.
Wood Fiber
Lightweight
Minimum Waste
Compatible
Engineered Services

TJI Joist
®
(Wood I)
TJS Truss
®
(Open Web)
Timber Strand®(LSL)
Microllam ®(LVL)
Parallam ®(PSL)
LSL-Laminated Strand Lumber
LVL-Laminated Veneer Lumber
PSL-Parallel Strand Lumber

Wood Panel Products
 Structural Wood Panels
 Three major categories
 Plywood Panels
 Composite Panels – Core wood fibers (cabinet making)
 Nonveneered Panels
• OSB Oriented Strand Board (best of nonveneers)
• Waferboard
• Particleboard

Plywood veneer grades (& Composite Panels)
(Know table and descriptions Table 1 pp. 89)
Add “N” grade
Better than “A” – specialized veneer
N Best grade of face veneer
A
B
C
D W orst grade of face veneer

N
Figure 3.32 & 3.32
(See handout)

Figure 3.3