1 Dr. David Briggs Professor, Forest products & Operations Research Director, Stand Management &...

1

Dr. David BriggsProfessor, Forest products & Operations Research

Director, Stand Management & Precision Forestry CooperativesCollege of Forest Resources, University of Washington, Seattle, WA

Forest Products

2

Outline

I. Resource Background

II. Context for Wood Product Discussion

III. Structural Lumber Products

IV. Structural Panel Products

V. Wood-Nonwood Composites

File: ESRM 101/ESRM_101_Forest_Products

Last update: February 13, 2006

3

I. Resource Background

A. Global Consumption of Wood & Other Materials

B. Forest Resources in the US and WA

C. Harvest & Harvest Use in the US & WA

4

Softwood (Conifer)

5

Hardwood

6

A. Material Consumption (2005)

•Wood is the dominant material used by man

•Industrial Roundwood = wood for fuel (cooking, heating, etc) + industrial roundwood

•Industrial roundwood = wood (logs) for lumber, veneer, pulp, etc.

World Material Consumption, 2005

0

0.5

1

1.5

2

2.5

3

3.5

4 Billion Metric Tons Billion Cubic Meters

US Material Consumption, 2005

0

0.1

0.2

0.3

0.4

0.5

0.6 Billion Metric Tons Billion Cubic Meters

7

Global Wood Harvest & Use3.425 billion m3 (~ 2.1 billion tons)

0

500000

1000000

1500000

2000000

2500000

3000000

3500000

4000000

oo

o c

ub

ic m

eter

s

World

US

World

51% fuelwood (cooking & heating)

•49% industrial roundwood (logs)

(7%) utility poles, pilings, posts, log homes, etc

(26%) sawlogs & veneer logs

•lumber, veneer (plywood, etc.)

•chips sold to industries below

(10%) pulp & paper

•thinnings, tops & low quality logs from trees harvested for other products

•does not include chips from other wood industries or recycled fiber

(5%) OSB, MDF, hardboard, etc.

•US

•16% fuelwood

•84% industrial roundwood

8

B. Forest Resources in the US & WAUS Forest Land (747 million acres)

67%

7%

26%

Timberland Reserved Other

US Land (2,263 million acres)

33%

67%

Forest Land Other land

Washington Land (42.6 million acres)

51%49%

Forest Land Other land

Washington Forest Land (21.9 million acres)

80%

16%

4%

Timberland Reserved Other

9

B. Ownership of Forest Land

US Total Washington US Total WashingtonAcres, million 747 22 503 14Public 42% 55% 29% 49%Private 58% 45% 71% 51%

100% 100% 100% 100%PublicFederal

USFS 46% 67% 66% 71%BLM 15% 0% 4% 0%Other 16% 20% 5% 2%

State 19% 24% 20% 24%County, City 4% 3% 5% 3%

100% 114% 100% 100%PrivateForest Industry 16% 44% 19% 46%Non-industrial 84% 56% 81% 54%

100% 100% 100% 100%

Forest Land TimberlandForestland - reserved - low productivitySupports ≥ 10% tree cover

10

Public Land Ownership in WA

11

Ownership of Timber Volume: WA

47%

16%

19%

18%

USFS Other Public Industry NIPF

Ownership of Timber Volume: US

45%

11%

14%

30%

USFS Other Public Industry NIPF

Ownership of Timber Volume

• Volume is on Timberland

• Much of the volume on USFS and Other Public land is currently unavailable

12

Volume by DBH Class: OR & WA

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

6 8 10 12 14 16 18 20 21-28.9 >29

mil

lio

n c

ub

ic f

eet

1953 1963 1977 1987 1997

•Ave dbh harvested in 1976 = 27.5 inches•Most mills cannot process large diameter trees

•Ave dbh harvested in 1997 = 16.1 inches•Median log diameter = 11.4 inches

• Most of large diameter timber is on public land

and is unavailable

13

Removals in US: 16,021 million cubic feet

63%

37%

Softwoods Hardwoods

• Washington

– Supplies 5.4% of US total

– 7.9% of softwood

– 1.1% of hardwood

Removals in WA: 865 million cubic feet

92%

8%

Softwoods Hardwoods

B. Harvest Removals

14

Sources of logs in WA by landowner type

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

3,500,000

Lo

g v

olu

me

(M

bf,

Sc

rib

ne

r)

19681970

19721974

19761978

19801982

19841986

19881990

19921994

19961998

20002002

Calendar year ending December

National Forest Other public Forest industry own supply Other private

Ownership source of logs consumed by Washington sawmills,1968 to 2002

Source: WA State Mill Surveys (various) increasingdecreasing decreasing decreasing

15

Utilization of RemovalsUse of Hardwood Removals: US

31%

2%

34%

4%

28%

0%

1%

Saw logs Veneer logs Pulpwood Composite products

Fuelwood Posts, poles, and pilings Miscellaneous products

Use of Softwood Removals: US

52%

11%

28%

1%

5%

2%

1%



Use of Softwood Removals: WA + OR

71%

17%

2%

0%

6%4% 0%



Use of Hardwood Removals: WA + OR

46%

11%3%

0%

40%

0%

0%



16

What size? What properties?

II. Context for WOOD PRODUCTS

17

joists

wall framing

Long, “deep” pieces

“Quality” driven by strength & stiffness (design values) straightness (dimensional stability)

beams

1. Construction dominates US wood use

18

Solid-sawn softwood lumber consumption

Construction (Residential & Non-Res.) – 52% of Consumption

Repair and Remodeling – 30% of Consumption

0

5,000

10,000

15,000

20,000

25,000

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

SW

Lum

ber

Consu

mpti

on (

MM

BF)

Residential Construction

Repair & Remodel

Material Handling

Nonresidential Construction

19

2. Tree/log size is getting smallerAverage breast-height diameter of softwood timber harvested on private timberlands in the US

Pacific Northwest coast region and on DNR-managed trust lands in Washington state, 1976 to 2050

0

5

10

15

20

25

30

1970 1980 1990 2000 2010 2020 2030 2040 2050 2060


Mea

n D

BH

(in

ches

)

RPA Base Projection DNR recalculated sustainable harvest (est.)

Source: Haynes, R. (Ed.) 2003. An analysis of the timber situation in the United States: 1952 to 2050. USDA Forest Service, Pacific Northwest Research Station, Portland, Oregon

16 inch ave tree dbh DNR11.4 inch median log diameter in 1998; (Spelter FPL-RP-611, 2003)

12 inch diameter @ top of 5 m butt log 19 ringsAge of tree ~ 30 years

20

3. Trees of a given size can be grown in less time

• Juvenile wood:(red + yellow)

– red + yellow (cross-hatched)

– lower specific gravity (density)

– Higher microfibril angle

– Lower stiffness & strength

– More shrinkage

Age = 70Age = 30

Much more product from the fast grown tree

will be from the juvenile wood core

70 years 30 years

21

4. Visual grades do not assess wood properties

0

10

20

30

40

50

60

No. 1Peeler

No 2 Peeler No 3 Peeler No 1 Saw Special Mill No 2 Saw No 3 saw No 4 Saw

Percent Distribution of Douglas-fir Log Grades: (WA DNR Sales Cut volume. Dual Scaling Study in 2000)

No correlation between visual log grades and properties of wood inside!

>= 12 inches log diam.<= 2.5 inch knot diam.No rpi limit

Source: _____. 2001. Critique of cross-Border Comparisons Relating to British Columbia in the Department of Commerce’s Preliminary Determination. In the matter of: Countervailing Duty Investigation of Certain Softwood Lumber Products from Canada. Joint Report by H&W Saunders Ltd and Wesley Rickard, Inc. to Province of British Columbia and the BC Lumber Trade Council. Folio # 3.

>= 6 inches log diam.<= 3 inch knot diam.No rpi limit

A diameter sort!Quality is very variable

22

5. Engineered wood products (EWP) are replacing traditional products

• More efficient yield from smaller trees• Can combine wood “elements” from different trees to create

products with uniform, targeted properties

• Overcomes limitation of small tree size on product dimensions• Improves straightness and stability

16

II. Context for WOOD PRODUCTS

Wood “Elements”

Wood cells (fibers) Chemicals

“Solid” wood Wood fragments

Wood fragments, cont.

23

Many EWP’s use lumber & veneer that is stress-rated

for stiffness and/or strength glulam

Glulam, I beam & joist LVL, I-beam & joist

glulam LVL, I-beam & joist

24

Stress-rating measures stiffness

18

“Stiffness” MOE (modulus of elasticity, “E”)(bending test of lumber is shown, can do round logs also)

Stress at failure, Pmax

P’

D = deflection

max2

1.5P l

MORbd

Stress at proportional limit, P’'

21.5

P lFSPL

bd

Modulus of Elasticity

' 3

3

1

4

P lMOE

D bd

l = span; distance between center line of supports; generally not the length of the piece of lumber

b = breadth; either beam width or thickness depending on placement with respect to loading

d = depth through which load acts; either beam width or thickness depending on placement with respect to loading

25

Stress-rating Technology: Lumber & Veneer

Ultrasonic test

Mechanical test

26

Stress-rating Technology: Logs and Treesacoustic velocity estimates stiffness

Fibre-gen

ST 300Fibre-gen

HM 200™

TreeSonic

Fakopp

27

EWP designers place high & low rated “elements” where needed to achieve a specified product strength/stiffness

Low

High

High

28

Other EWP’s combine small elements, resins, plastics, etc. to get homogeneous, stiff, strong composites.

Strand lumber OSB, I-beam & joist

Parallam lumber Wood/plastic

29

III. Structural Lumber Products

A. Solid-sawn lumber

B. Engineered composite lumber1. Laminated & Finger-jointed lumber

2. Lumber from veneer

3. Lumber from strands

4. I-beams & joists

C. Competitors: steel, concrete

30

A. Solid-sawn softwood lumber

31

0

1,000

2,000

3,000

4,000

5,000

Lu

mb

er p

ro

du

cti

on

(M

Mb

f)

0

50

100

150

200

250

19681970

19721974

19761978

19801982

19841986

19881990

19921994

19961998

20002002


Lumber production (LHS)Number of sawmills (RHS)

Comparison of annual lumber production with number of mills forsawmills in Washington, 1968 to 2002

Source: WA State Mill Surveys (various)

WA: 13% of US Softwood Lumber Production

Production increasing but number of mills is decreasing a few large highly efficient ones

32

Log Size/Quality & Mill TechnologyAverage breast-height diameter of softwood timber harvested on private timberlands in the US

Pacific Northwest coast region and on DNR-managed trust lands in Washington state, 1976 to 2050

0

5

10

15

20

25

30

1970 1980 1990 2000 2010 2020 2030 2040 2050 2060


Mea

n D

BH

(in

ches

)

RPA Base Projection DNR recalculated sustainable harvest (est.)

Source: Haynes, R. (Ed.) 2003. An analysis of the timber situation in the United States: 1952 to 2050. USDA Forest Service, Pacific Northwest Research Station, Portland, Oregon

11.4 inch median log diameter in 1998 (Spelter FPL-RP-611, 2003)

Difficult to get large lumber dimensions from small trees/logs

33

Tree/log size limits ability to get pieces needed for large, open room spans

joists

Wall framing

S4L quality is driven by strength & stiffness design values straigtness

34

Quality is highly variable from tree to tree

• Variability due to biology of how trees grow & produce wood

• Leads to non-uniform performance of solid-sawn lumber

Age = 70Age = 30

•red (natural): high average, high variation, low safe design value•Blue, green (engineered) low variation & higher design values

35

B. Engineered composite lumber products 1. Glued Laminated Lumber (GLULAM beams)

(APA the Engineered Wood Association)

• Composed of wood laminations, or "lams," bonded together with strong, waterproof adhesives.

• “lams” are typically lumber two inches or less in thickness and can be a variety of species.

36

Glulam Applications: Residential (APA the Engineered Wood Association)

37

Glulam Applications: Nonresidential (APA the Engineered Wood Association)

Large open areas Curved arches

Bridges

38

2. Finger-jointed/Edge Glued Lumber• Composed of small pieces, often salvaged from slabs, edgings, and end

trims from lumber manufacture) bonded together with waterproof adhesives.

• Finger-join end to end, then edge to edge to get wider pieces, then top to bottom to make thicker pieces

39

2. Lumber from Veneer• Laminated veneer lumber (LVL), also called structural composite

lumber (SCL) is created by layering dried and graded wood veneers with waterproof adhesive into blocks of material known as billets that are cured in a heated press. The billet is then sawn to various dimensions.

• In LVL, the grain of each layer of veneer runs in the same direction, rather than cross-lamination which is typical of other engineered wood products such as plywood. LVL out-performs conventional lumber when either face- or edge-loaded and is virtually free from warping and splitting

40

LVL Applications (APA The Engineered Wood Association)

LVL glued side-by side to make thicker beam

LVL in flanges of I-beams & joists

LVL in standard lumber sizes

41

3. Lumber from Strands• Oriented strand lumber (OSL), parallel strand lumber (PSL) and similar

products are manufactured from waterproof heat-cured adhesives and long, rectangularly shaped wood strands that are arranged in parallel to the length of the product.

• Strand products are made as large, continuous mats or billets, that are sawn into various dimensions.


42

OSL Applications (APA the Engineered Wood Association)

Headers

Framing

•The lumber analogue to oriented strand board but

• longer strands

•more alignment

•made to mimic lumber sizes & uses

43

ParallamLonger strands (from veneer) pressed into a large (20x20) cross-section continuous billet. Sawn off to desired length and ripped to beam and column sizes. Can see this at new CUH building.

44

4. Wood I-beams, joists & trusses• I-joists are comprised of top and bottom flanges of various widths united

with webs of various depths. • The flanges resist common bending stresses, and the web provides

outstanding shear resistance• Flanges may be solid-sawn lumber or structural composite lumber (LVL)

for Web may be plywood or oriented strand board (OSB).


45

4. Wood I-joists & trusses

LVL or machine stress graded lumber flanges & oriented strand board web

46

C. Competitors: Steel, Concrete, etc.

Require much more energy to produce than woodMuch greater demand for fossil fuelsMuch greater carbon emissions

47

IV. Structural Panel Products

A. Plywood

B. Oriented Strand Board

C. Structural Insulated Panels

D. Particleboard

E. Fiberboards

48

A. Plywood

Veneer manufacture

Sheet

Grain in any sheet is perpendicular to adjacent sheets

• Manufactured from thin sheets of cross-laminated veneer and bonded under heat and pressure with strong adhesives.

49

Wall & Roof Sheathing, sub-flooring, siding (APA the Engineered Wood Association)

50

Overlaid PlywoodConcrete forms Skid-resistant surfaces

Billboards, highway signs

51

B. Oriented Strand Board (OSB)• OSB is manufactured from waterproof heat-cured adhesives and rectangular-

shaped wood strands that are arranged in cross-oriented layers. • Produced in huge, continuous mats, which are sawn to standard panel sizes• OSB is a solid panel product of consistent quality with no laps, gaps or voids • A structural wood panel with many of the strength and performance characteristics

of plywood.


52

OSB Surfaces

• OSB rough side up for traction • OSB smooth side

53

Wall & Roof Sheathing, sub-flooring, siding (APA the Engineered Wood Association)

54

C. Structural Insulated Panels (SIP)

Thick insulating foam between plywood or OSB panels

55

D. Particleboard• INPUT: Sawdust, planer shavings, etc., by-products of other wood industries, not

logs• Same process as OSB & LSL but smaller wood elements• Usually 3 layers of particles: those in center are coarser than those on surfaces

56

Particleboard Usesmelamine overlay shelving, table tops, etc. flooring or floor underlayment

Veneered for furniture and cabinets

57

E. Fiberboard (pulped fibers)

1. Hardboard

2. Insulation board

3. Medium density fiberboard (MDF)

58

1. Hardboard

59

2. Insulation board• Low density SGg ~ .27-.43

17-25 lb/ft3

• Generally flat sheets• Process

– Similar to wet process hardboard but no hot press is used

– Product thickness is controlled by a simple roller after which the panel is dried

• Uses– Exterior walls of houses

apply panels over the studes and under the siding

– Acoustical ceiling tiles– CELOTEX panels used in

interior wall partitions in buildings; has been largely replaced by gypsum board

60

3. Medium Density Fiberboard (MDF)• Medium Density Fiberboard (MDF) is a grainless composite panel

product made from extremely fine wood fibers and manufactured in sheets of various dimensions.

• It is ideally suited for a wide variety of woodworking applications including cabinets, shelving, furniture, store fixtures, moulding and flooring.

Temple-Inland

61

MDF, exterior siding and trim

62

V. Wood – Non-Wood Composites

A. Wood & Gypsum B. Wood & CementC. Wood & Plastic D. Wood & Fiberglass, Metal, Kevlar, …

63

A. Wood/Gypsum Composite: drywall

• Interior wall board – “drywall”,

sheetrock

• Gypsum with paper surface: US

• Gypsum mixed with recycled paper fiber and pressed into a wallboard panel: Europe

64

B. Wood/Cement Composites: Siding

Hardi-plank: cement, sand, & wood fiber; simulated wood grain

65

Wood/Cement Composites: Roof Tile

• Wood Fiber & cement

• Molded to simulate cedar shake

topbottom

66

C. Wood/Plastic Composite: “Lumber”• Recycled plastic shopping

bags & recycled wood fiber from paper

• Molded into lumber shape• Decks, park benches, etc.• Poor chemical bonding• Low strength & stiffness• Degrades

– Ultraviolet– Water gets in to the wood

particles which swell & shrink

– As opens up, wood decay starts

67

Combine Wood Flour with Plastics & Extrude

• New Wood Materials Engineering Lab at WSU

• Wood flour, plastic resins, additives– Excellent chemical

bonding– High strength & stiffness

• Extruded into various shapes

• Decks (Ex Trex and others), windows

• Siding & roofing products under development

68

D. Wood, Metal, Glass, Vinyl, etc. (Weathervane Windows)

• Modern high efficiency windows– Pre-finished exterior skin;

vinyl or aluminum– High efficiency glass– Solid wood on interior for

natural look– Hollow extruded exterior

frame of wood-plastic composite; negligible shrink & swell

69

Questions?

1 Dr. David Briggs Professor, Forest products & Operations Research Director, Stand Management &...

Documents

Transcript of 1 Dr. David Briggs Professor, Forest products & Operations Research Director, Stand Management &...