TIMBER BLD62003 BUILDING MATERIALS

BACHELOR OF QUANTITY SURVEYING (HONS.)

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INTRODUCTION

• One of the ancient building materials.

• Used in almost all parts of the world for centuries.

• Loved by all as it is strong and stiff, yet by far the least dense material in the construction sector.

Hōryū-ji ( Temple Of The Flourishing Law)

year 607

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WHAT IS TIMBER?

• Natural material

• Renewable source

• Aesthetically beautiful with

various colors, tones and grains

• Creates warm feeling

• Has natural thermal insulation

qualities

• High strength relative to its weight

• A degree of natural durability

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TIMBERS IN MALAYSIA

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TYPES OF TIMBER in MALAYSIA BLD62003_MAK_TIMBER

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AGATIS ALBAZIA KAPUR

MEMPHENING NYATOH SERAYA

20 TYPES OF MOST POPULAR TIMBER

in MALAYSIA BLD62003_MAK_TIMBER

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• Balau (Shorea spp.)

• Bintangor (Calophyllum spp.)

• Chengal (Neobalanocarpus heimii)

• Dark Red Meranti (Shorea spp.)

• Gerutu (Parashorea spp.)

• Kasai (Pometia spp.)

• Kelat (Syzygium spp.)

• Keledang (Artocarpus spp.)

• Keruing (Dipterocarpus spp.)

• Mengkulang (Heritiera spp.)

• Merbau (Intsia spp.)

• Nyatoh (Spp. of Sapotaceae)

• Kembang Semangkok

(Scaphium spp.)

• Kempas (Koompassia

malaccensis)

• Red Balau (Shorea spp.)

• Yellow Meranti (Shorea spp.)

• Sepetir (Sindora spp.)

• Mersawa (Anisoptera spp.)

• Merpauh (Swintonia spp.)

• Heveawood (Hevea brasiliensis)

See more at: http://mtc.com.my/timber-products/#sthash.A8VCa1Zv.dpuf http://www.etawau.com/Timber/Wood.htm

PRICES OF TIMBER IN M’SIA

SPECIES LOGS/TON SAWNTIMBER/M3

18" UP GMS STRIPS SCANTLINGS

HEAVY HARDWOOD

Chengal 4,000 6,638 2,966 8,828

Balau 2,820 2,825 2,12

6 3,531

Red Balau 2,500 2,966 1,977 3,178

Merbau 2,650 3,778 3,107 2,772

Mixed Heavy

Hardwood 830 812 784 742

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AVERAGE DOMESTIC PRICES OF LOGS, SAWN TIMBER,

PLYWOOD AND MDF IN PENINSULAR MALAYSIA (JUNE 2015) * All prices are in Ringgit Malaysia (RM)

* All prices are indicative only

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AVERAGE DOMESTIC PRICES OF LOGS, SAWN TIMBER,

PLYWOOD AND MDF IN PENINSULAR MALAYSIA (JUNE 2015) * All prices are in Ringgit Malaysia (RM)

* All prices are indicative only

MEDIUM HARDWOOD Keruing 1,400 1,766 1,271 2,203

Kempas 1,210 1,780 1,695 2,010

Kapur 1,700 2,248 752 2,331

Mengkulang 1,100 1,412 925 1,575

Tualang 1,310 2,260 1,377 2,295

PRICES OF TIMBER IN M’SIA BLD62003_MAK_TIMBER

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AVERAGE DOMESTIC PRICES OF LOGS, SAWN TIMBER,

PLYWOOD AND MDF IN PENINSULAR MALAYSIA (JUNE 2015) * All prices are in Ringgit Malaysia (RM)

* All prices are indicative only

LIGHT HARDWOOD

Dark Red

Meranti 1,900 2,190 1,601 2,754

Red Meranti 1,760 1,589 1,271 1,624

Yellow Meranti 1,150 1,400 1,165 1,400

White Meranti 1,040 2,119 1,521 1,695

Mersawa 1,470 1,483 989 1,412

Nyatoh 900 777 565 1,201

Sepetir 850 1,107 918 1,118

Jelutong 1,000 1,391 1,285 1,540

Mixed

Hardwood 1,150 812 706 648

PRICES OF TIMBER IN M’SIA BLD62003_MAK_TIMBER

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AVERAGE DOMESTIC PRICES OF LOGS, SAWN TIMBER,

PLYWOOD AND MDF IN PENINSULAR MALAYSIA (JUNE 2015) * All prices are in Ringgit Malaysia (RM)

* All prices are indicative only

MALAYSIAN

RUBBERWOOD

Hevea brasiliensis

LOGS/TON SAWN TIMBER/M3

160

1" X 1" 2" X 2" 3" X 3" 4" X 4"

706 1,045 1,080 1,186

PLYWOOD 4' X 8'

(RM per piece)

4mm 6mm 9mm 12mm

14.60 22.00 34.50 41.50

MDF 4' X 8'

(RM per piece)

4mm 6mm 9mm 12mm

12.10 15.80 21.70 28.10

http://www.mtib.gov.my/index.php?option=com_content&view=article&id=8

7&Itemid=88&lang=en

PROJECTS USING MALAYSIAN

TIMBER

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PROPERTIES OF TIMBER

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PROPERTIES OF TIMBER

• Not an electricity or heat conductor

• Highly combustible hence burns quickly

• Varying weight in different sorts of wood compositions

• Opaque/ solid

• Not a renewable source of energy

• Color: brown of slightly red

• A biological material

• A fuel – producing heat energy when burnt

• Shrinks due to water loss through evaporation

• The drier the timber is the stronger it will be

• Some timber requires moisture to stabilize equilibrium with the outside air by exchanging moisture with relevant temperature & humidity

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• Timber is an orthotropic material; grows in a vertical manner.

• Fibrous material

• Cellular organic material made up mainly of cellulose.

• Strength of wood does not depend on the length of fibers but on the thickness of the cell walls.

• Wood’s finely porous structure make it a relatively suitable material for insulation

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• Dimensional changes in wood may be affected by temperature and moisture.

• Heating of wood results in an expansion due to high temperature but also a shrinkage due to the subsequent loss in moisture.

• Timber is a poor conductor of heat(denser timbers are better conductors)

• Corrosion resistant

• Natural product, so it has color variations

• High firmness with good elasticity

• High absorption capacity

• Naturally resistant to chemical action, making it a suitable building material in chemically adverse environments

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• Resistant to passage of electric current

• Some species of wood are decay resistant and resist attack of insects such as termites.

• For example: Cedars, Redwood, Cypress, Black walnut and Black locust.

•

•

Cedar

Cypress Black locust Red wood

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• Wood provides a good sound insulation when combined with other materials in construction.

• Sound absorption values for wood differ with moisture content, direction of the grain and density.

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CHARACTERISTICS OF TIMBER

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CHARACTERISTICS

• Contains: i. 70% cellulose

ii. 25% lignin (provides strength)

iii. Extractive i.e tannin, starch, oil, resin, fat and wax

• Categorized into 2 types: (i) Softwood; (ii) Hardwood.

• But in Malaysia, they are categorized into 4 types.

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TIMBER

Heavy hardwoods

(Belian, Cengal)

Medium Hardwoods

(Rasak, jati, merbau)

Light Hardwoods

(Semangkok, Nyatoh)

Softwood

(Ramin)

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FORMATION – 2 layers

Darker brown lines at the center

• Called the late wood, hardwood or summer wood

• Dense than the lighter brown

Lighter brown lines at the outmost

layer

• Called the early wood, sap wood or spring wood

• Softer than the darker brown

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FORMATION – 2 Layers BLD62003_MAK_TIMBER

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DARKER BROWN LINES LIGHTER BROWN LINES

Softwood VS. Hardwood Softwood Hardwood

Definition Conifer trees, needle-shaped leaves that mostly grows in northern temperate zone. Mostly evergreen.

Broad-leafed trees, which loses their leaves in autumn as they are deciduous.

Growth rate Has a higher growth rate Has a lower growth rate

Density Has a lower density, thus softer than hardwood

Has a higher density

Cost Less expensive More expensive

Fire Resistance Better Poor

Uses Wood ware (homes and cabins), furniture, finishes

Flooring, furniture

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HARDWOOD BLD62003_MAK_TIMBER

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BENEFITS: • Adds warmth and

beauty • Can add lasting

value to interior façade (home, office etc)

• Offers great design flexibility

• Does not retain dust, pollen and other allergens

• Low maintenance • Enhances room

décor and offers ageless beauty

HARDWOOD

• Hardwoods are mainly obtained from deciduous trees.

• Deciduous trees are also known as broad leaf trees.

• Timber for engineering purpose is obtained from these trains as the trees have hard woods that are strong and are dark colored.

• They are obtained from tress such as oak, walnut, teak etc.

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TEAK Properties: Teak is a hard hardwood, it is heavy and strong. It has a high durability and is strong in strength. Teak originated in India and Burma. Uses: Teak is used to build boats, cabinets, other furniture, flooring and decorative veneers. Other: It is best to use an oil finish when using teak. It can also be difficult to glue and its dust has known to be an irritant.

AMERICAN BIRCH Properties: American Birch is a hard hardwood, it is heavy and strong but has a low durability. It originated from USA and Canada. Birch also finishes well. Uses: Making furniture, quality joinery, dowels and flooring. It is also used in the manufacture of plywood.

ENGLISH ELM Properties: English Elm is a hardwood with an intermediate hardness. It has an intermediate weight and low durability. It finishes well but is not suitable for exterior work. Uses: Used for cabinet making, Windsor chairs, boat building, flooring and coffins

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SOFTWOOD

• Softwoods are mainly from coniferous tress.

• Coniferous trees are also known as evergreen trees.

• These kinds of trees bear softwood that are light in color, light in weight and weak.

• They can be used for decorative purpose only.

• They are obtained from trees such as larch, pine, spruce etc.

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DOUGLAS FIR Properties: Douglas- fir is a softwood, it Uses: Douglas-fir is commonly used in the construction industry. It has also been used for home built aircraft. They are also the most common Christmas tree in the USA

WESTERN RED CEDAR Properties: Western Red Cedar is a lightweight softwood that has a high durability and finishes well. It originated from Canada, UK and the USA. It is weak and is soft. Uses: Garden sheds, greenhouses, exterior boardings, fencing and posts. Notes: When nailing Western Red Cedar it is best to use galvanised or copper nails. This timber is not a true cedar

YELLOW PINE Properties: Yellow pine is a softwood that has an intermediate weight and is also strong. It also has a intermediate durability and finishes well. Uses: Construction work, shipbuilding, flooring, joinery work, crates and pallets

SOFTWOOD BLD62003_MAK_TIMBER

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TYPES OF TIMBER BLD62003_MAK_TIMBER

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Timber

Natural solid timber Engineered timber products

Plywood Fiber

boards Particle boards

Block board

Laminates Veneers

NATURAL SOLID TIMBER BLD62003_MAK_TIMBER

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• The tree logs are converted into commercially

feasible sizes.

• It is easy to provide carpentry joints in solid

timber

• It is 100% recyclable material

• Depending upon the type of tree it is generally

hard, stiff & has high strength and durability

• The age of timber furniture is longest : more the

50 years

• Repair and maintenance is easy but regular

maintenance is advisable

• It requires less labor than metallic work and is

easily available

• It is likely to crack and decay if not properly

seasoned and treated

• It is not advisable if there is a risk of fire or

regions of high humidity and natural storms

CONVERSION OF TIMBER

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Conversion of Timber • A process of cutting logs into sections before

seasoning.

Type of Cuts

A. Plain sawn / Through and through o Mostly produces tangentially sawn

timber and some quarter sawn. o Most economical o The center of the tree (pith) is removed as it is soft and splits o Easily distort during seasoning

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PLAIN-SAWING

i. Parallel cut of log into boards

ii. Varies in grain pattern

iii. Tend to twist and wear unevenly

Advantage: The most economical way of sawing logs - it gives the greatest possible amount of lumber with the least waste. Disadvantage. Plain sawed lumber usually warps very badly. Effect of warping of lumber. • There is always considerable moisture in the form of

sap. • When the tree is cut down, the sap ceases to circulate,

and the moisture in the log begins to evaporate. • As the log dries, all of the concentric rings,

representing the annual growths, become a little shorter and thus cause the log to crack.

• If it has been sawed into boards it will, of course, dry even more rapidly, causing the portion of the rings in each board to shorten considerably, and thus bend or warp the board, as shown in the illustration.

PLAIN SAWN

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B. Quarter Sawn

• Timber is cut with the growth rings meeting the surface not less than 45 degrees.

• More decorative and does not distort easily

• Produces more waste.

• More expensive.

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• In order to overcome this tendency to warp, another method of sawing has been devised.

• This method also adds great beauty to the

appearance of the boards by exposing the medullary rays.

• The log is usually cut into quarters as the first

operation.

• There are a number of different methods of quarter sawing, but they all have the same purpose in view, that of cutting the boards as nearly as possible in a direct line from the bark to the heart.

QUARTER SAWING

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QUARTER SAWING BLD62003_MAK_TIMBER

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Section A

• Each board perfectly quartered

• Very wasteful: so many wedge-shaped pieces that cannot be used

Section B

• Fairly good results but not as perfect as A.

• A wasteful method on account of the great number of small pieces left.

Section C & D

• Very good quartered effect

• Common methods of producing quartered oak lumber.

• The irregular pieces left at the corners are usually cut into stock of some other character.

RIFT SAWING

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Rift-sawn boards are probably the least desirable of all the cuts. This is because these cuts can vary quite a bit depending on where in the log they are cut. They also tend to "move" in two directions with makes them poor choices for flooring, table tops and decking. Rift cut is often left for building materials like 2x4, 2x6s, 4x4 and so on. This does not mean that good quality hardwoods are not available in rift-sawn cuts, only that it is often not the ideal cut

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RIFT SAWING

SEASONING OF TIMBER

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Seasoning • A process where the wood is dried or moisture content is

reduced to a level where it is suitable to be used.

Types of Seasoning

A. Air Seasoning o Timber, protected from the ground and

rain are stack in layers separated by strips of wood (stickers) which control the passage of air.

o The warm air, circulated by the wind removes the moisture.

o Timber ends are protected by waterproof coatings to avoid splitting.

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B. Kiln Drying • Heating timbers in a closed chamber with

precise temperature and humidity

• Timber is not degraded

• Timber is normally air dried to a fiber saturation and then kiln dried.

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KILN DRYING PROCESS BLD62003_MAK_TIMBER

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VIDEO ON KILN DRYING

PROCESS BLD62003_MAK_TIMBER

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ADVANTAGES &

DISADVANTAGES OF TIMBER

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ADVANTAGES BLD62003_MAK_TIMBER

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Renewable resource

High electrical resistance

Suitable for construction in all types of climatic

zones

Reduce waste Improve

efficiency of material usage

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Good thermal insulation

Good sound absorption

Compatible with traditional skills

Requires less energy High strength

Reduce environmental problems caused by

excessive timber harvesting

Save cost and waste of sawing

Long span of life time

Demolished timber structures can be

cycled as building material (i.e burnt as

fuelwood)

• High costs and diminishing supplies of timber

• Distortions, shrinkage and splitting.

Distortions Shrinkage Splitting

DISADVANTAGES OF TIMBER BLD62003_MAK_TIMBER

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• Extreme hardness of some dried timbers.

• Discoloration, brittle and erosion.

Discoloration Erosion

• High toxicity of chemical preservatives.

DISADVANTAGES OF TIMBER BLD62003_MAK_TIMBER

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• Wood Decay

(Caused of Mold and Fungal Stains)

Mold Fungi BLD62003_MAK_TIMBER

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• Termites

• Marine Borers

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DISADVANTAGES OF TIMBER

TREATMENTS & PROTECTIONS

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Treatments and Protections • Known as control in the case of wood that has

already been infested, or as preventive protection, to ensure no infestation takes place.

Methods of Protection

• Only timber that has been well dried (moisture content less than 20%) should be used.

• Fire-retardant treatment (FRT) is done by placing lumber in a vessel and impregnating it under pressure with chemical salts to reduce its combustibility.

• Wood preservatives (pesticides, insecticides) are used , but used at a limit to avoid environmental damage.

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• Waterborne salts (wood preservative) are most widely used.

• Most common is the chromatid copper arsenate (CCA)

• These preservative are either brushed or sprayed onto wood. However, pressure impregnation last the longest as it drives the chemical deeply into the fibers.

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FUNCTIONS AND

APPLICATIONS

OF TIMBER

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cladding

roofing

fencing

decking

flooring

beam structure

APPLICATION OF

TIMBER

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APPLICATION OF TIMBER

• Building structural

• Cabinet & furniture

• Internal finishes

• Construction

i. Light frame timber construction

ii. Heavy frame timber construction

• Wood panel products

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VENEER WOOD PANEL

• Thin sheets of wood cut form a log.

• Thinner than 3mm thick.

• Glued onto core panels (typically, wood, particle board or medium-density fiberboard) to produce flat panels such as doors, tops and panels for cabinets, parquet floors and parts of furniture.

• Hand selected & assembled panel, made to order.

• These panels do not require any extra finishing

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LAMINATE WOOD PANEL

• Manufactured timber made from thin sheets of substrates or wood veneer.

• It is similar to the more widely used plywood, except that it has a plastic, protective layer on one or both sides.

• Can be produced as large as possible for beams or in thin layers of furniture.

• Reasons to laminate wood: size, shape and quality.

• Carry out seasoning before laminate the wood.

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LAMINATE FLOORING - Video BLD62003_MAK_TIMBER

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PLYWOOD

• Made by gluing together thin veneers or piles of softwood or hardwood.

• The more veneer the stronger the plywood.

• Types of glue and veneers determine suitability for application.

• Fresh qualities vary where some have attractive grains whilst some contain knots.

• Maybe used as interior or exterior purposes.

• Different grades are used for internal and external use depending on water resistance of the glue used to stick the piles together.

• Used to form pitched roofs or form folded-plate roof structures.

• Lower grade materials used as formwork for in-situ concrete.

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PLYWOOD

• REGULAR GRADE PLYWOOD

Temporary usage

• COMMERCIAL PLYWOOD

Also known as interior grade or moisture resistant (MR) grade plywood

Used for making furniture that is unlikely to get wet

• MARINE PLYWOOD

Superior quality and also expensive

Used for making furniture or products that are subjected to prolonged water exposure

Used mainly for industrial purposes and boat building.

• WATER PROOF PLYWOOD

Also known as exterior grade or Boiling water resistant (BWR) grade plywood.

Used for making furniture that is likely to get wet i.e. kitchen furniture.

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TYPES OF APPLICATION

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TIMBER FINISHES

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1. Wax

• Type :

or

• Characteristic : look like freshly cut unfinished wood, smooth feel, softer than lacquers and varnishes.

• Protection : melt at low temperature, little protection against scratches and wear, not penetrating the wood, prevent oxidation.

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2. Paint

• Type :

• Characteristic : bright white appearance, not preservative, appear in most of the building

• Protection : protect wood from weathering,

conceal some surface defeat

cleanable surface with many color

to retard penetration of water

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3. Solid color stain

• Type :

• Characteristic : long lasting, opaque surface, vibrant color

• Protection : waterproof, UV protection

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TIMBER PRODUCTS

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• Small strips of wood are joined

together with glue to form a

larger element.

• Stable

• High Bearing Capacity

• It can used as a building

structure or finishing element.

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GLUED LAMINATED

TIMBER (GLULAM)

Laminated Veneer Lumber (Microlam)

• It uses many layers of thin wood treated with adhesives.

• Economical

• Lower tendency to shrink or twist

• Suitable in columns, beams and purlins

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Plywood

• Manufactured by laminating a series of thin timber layer

• Grains direction are at right angles to each other

• Used as a lining, flooring surface, complex roof structures, formwork

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Wood Particleboard (Chipboard)

• Uses wood waste or forest thinning, which are converted into wood chips.

• Made by compressing the sawdust and plane shavings with adhesives.

• Used in furniture industry

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Cement-bonded particleboard

• Manufactured from a mixture of wood particles and cement.

• Contains 75% of cement to fill up voids

• Good sound-insulation

• Resistant to fire, water and fungal

• Used as soffits, roofing, and flooring

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Oriented Strand Board (OSB) • Made from long strands of

wood compressed and glued

into three to five layers.

• Strands are oriented in the

same method as plywood.

• Used for sheathing and

subflooring of light frame

wood buildings.

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Fiberboard • Fine-grained board made of wood fibers and synthetic

resin binders.

Medium Density Fiberboard

o Manufactured by dry wood fibers in addition of adhesives

o Used as furniture panels and as internal load bearing applications.

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Hardboard (HDF) • Densest fiberboard

• Density of 900kg/𝑚3

• Used as paneling, wall and ceilings linings, floor underlays and furniture.

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Comparison of Timber Products

Laminated Veneer Lumber (LVL) and Plywood

LVL Plywood

Orientation of Grains (Veneer Layers)

Grains are parallel to each other

Grains are in a direction that are perpendicular to each other to have uniform strength and reduce moisture movement

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LVL vs. Plywood

Plywood and Oriented Strand Board (OSB)

Plywood OSB

Composition of Material

Thin layers of veneers that are glued and laminated.

Dried wood strands mixed with adhesives an wax to form thick mats.

Cost More expensive Less expensive

Economical Uses good logs called peelers

Uses small trees and branches

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Plywood vs. OSB

Particleboard and Fiberboard

Particleboard Fiberboard

Materials used Wood dust Wood fibers

Durability Weaker Stronger

Ability to mold Hard to mold as it is easily chipped

Easy to mold into shapes as it is hard to chip or break

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COMMON TIMBER DEFECTS

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Wood Defect

Features Caused By Effect Solution

Blue Stain

A bluish gray discoloration on the woods surface. This feature is most common in woods like Holly, Pine, and Sycamore.

Mold that grows in warm and moist area, usually poorly ventilated.

Discoloration of wood.

Can be cut off, placed out of sight, or concealed with a dark stain.

Bow

A curve along the face of a board that usually runs from end to end.

Improper storage. Usually moisture evaporation from one side and not the other.

Stock is difficult to work with and cut.

Cut in to smaller pieced, even out on a jointer, or nail (screws are better) in place with bow bulging out.

Checks or Splits

Breaks at the end of a board that run along the grain. Checks and splits are usually restricted to the end of a board.

Rapid Drying. Can effect the strength

and appearance of the board.

Should be cut off or worked around.

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Blue Stain Checks or splits

Worm hole

Dead /Loose knot Gum, Sap, or Pitch

Cup

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Wood Defect

Features Caused By Effect Solution

Crook

Warping along the edge from one end to the other. This is most common in wood that was cut from the center of the tree near the pith.

Can be caused by improper drying and storage or the presence of reaction wood.

Can be difficult to work with.

The higher spots can be cut away on a table saw or jointer using a special jig.

Cup

Warping along the face of a board from edge to edge. This defect is most common of plain-sawn lumber.

This defect can be caused when one board face dries at a faster rate than the other.

Stock can be difficult to work with. Trying to "force it flat" can cause cracking along the grain.

You can try allowing the board to dry at the same moisture content under pressure, rip it into smaller pieces on a table saw, or use a jointer to remove the high spots.

Dead or Loose Knot A dark, usually loose knot.

This is caused by a dead branch that was not fully integrated into the tree before it was cut down.

Can mar the appearance of the wood, fall out, become loose, or weaken stock.

Should be cut out, around, or glued in place and filled with a wood putty.

Gum, Sap, or Pitch

Accumulations of a resinous liquid on the surface or in pockets below the surface of wood.

Injury to the tree. May cause difficulty when finishing.

Should either be cut off or scraped out and filled.

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Machine Burn Dark streaks along the

face of a board.

Usually caused by

planer blades that are

dull or spun on a part

of the board for too

long.

Discoloration to the

surface. Sometimes

the burn can

penetrate into the

board.

Can be sanded off or

cut down with a

jointer. The depth of

the board often

determines the

amount of work

needed.

Ring check

Breaks in the wood

along the annual

growth rings.

Improper drying or

damage during

transport.

Can effect strength or

appearance.

Should be cut around,

place out of sight, or

glued down.

Tight knot

A know which is tightly

integrated into the

surrounding wood.

This was once a

branch that was

incorporated into the

tree as its girth

increased.

Does not effect the

lumber's strength.

May be removed for

appearance purposes.

Some lumber such as

Knotty Pine, is highly

prized for this feature.

Twist

Warping in lumber

where the ends twist

in opposite directions.

(Like twisting a towel)

Growing conditions,

uneven drying or the

presence of wood

reaction.

Can be difficult to

work with.

Can be cut into

shorter boards or the

high spots can be

removed on a jointer.

Wormholes Small holes in the

wood.

This is caused by

insects boring through

the wood.

Can be used to

simulate old or wormy

wood.

Cut around worm

holes or uses as is for

decorative purposes.

Be sure the insects

are dead.

Wood

Defect Features Caused By Effect Solution

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ADDITIONAL INFO ON

SEASONING

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ADDITIONAL INFO ON SAWING

TRUNKS

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References 1. Book References

Allen, E. and Iano, J. 2009. Fundamentals of

Building Construction : Materials and

Methods. 5th ed. Hoboken: John Wiley & Sons

Inc.

American Institute of Timber

Construction, 2005. Timber Construction

Manual 5th ed., John Wiley & Sons, INC.

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Lyons, A., 2007. Materials for Architects &

Builders. 4th ed. Oxford: Elsevier Ltd.

Slavid, R., 2009. Wood Architecture,

Laurance King Publishing Ltd.

Spence, WP., and Kultermann, E., 2011.

Construction Materials, Methods, and

Techniques: Building for A Sustainable Future 3rd

ed. Cengage Learning.

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Steiger, L., 2007. Basics Timber

Construction, Birkhauser.

Stulz, R. and Mukerji, K., 1993.

Appropriate Building Materials.

Oxford: Intermediate Technology

Publications.

Torre, F., 2008. Materials: A

Sourcebook for Walls and Floors,

Steward, Tabori & Chang.

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TUTORIAL QUESTIONS

• Explain TWO (2) types of the conversion of timbers.

• Differentiate FIVE (5) characteristics of softwood and

hardwood.

• Explain FIVE (5) examples of Natural and Seasoning

timber defects, respectively.

• Describe THREE (3) applications of timber.

• Name and explain TWO (2) types of timber seasoning.

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