Wood as a building material

WOOD

Different woods are the palette of the furnituremaker. They provide color and texture, strength and beauty to handmade furniture.

Each type of wood has characteristics to be considered when building a piece of furniture. Some are very hard and durable; some are flexible and suitable for bending. "Hardwood" is a term applied to trees that lose their leaves in winter. "Softwood" describes evergreens such as fir, pine and redwood. The actual durability a wood is described in a range from very soft to very hard.

Every wood has a distinctive grain structure. Woods such as white and red oak, ash and walnut have "open-pores". These woods have small holes in their surface that give the piece a textural quality. When a stain is applied to this type of surface, the stain tends to collect in the "open-pores" and appears darker than the rest of the piece. Tight grained woods include maple, alder, and cherry. These woods are smooth to the touch and can take finish evenly.

The color and grain look of different types of wood

California Softwoods and HardwoodsAlder, Pacific Maple, Black Oak, Madrone, Tan Oak, Redwood, Myrtlewood(pepperwood), Claro Walnut, Western Red Cedar, and Yew

Humboldt County woodworkers prize the unique woods of the Pacific Northwest for their beauty and durability. Local woodworkers use native woods alone and in combination with domestic and exotic species creating the furniture that is part of the distinctive designs of Northern California.

AlderWarm brown color with a figure like cherry. Alder is a medium soft wood suitable for cabinetry and furniture with the appropriate sized joinery.

Pacific MapleGolden yellow wood with a variety of figure available, can be found in the curly or fiddleback varieties. This is a medium hard wood suitable for all types of furniture.

MadroneOne of the harder California native woods, Madrone has a reddish pink color with streaks of color throughout. Madrone is used in furniture and turnings, and can be used in flooring and architectural woodwork.

Softwoods and HardwoodsAsh, Basswood, Beech, Birch, Butternut, Tennessee Aromatic Cedar, Cherry, Fir, Hickory, Maple, Pine, Poplar, Red Oak, Walnut, White Oak.Long a staple of the American furnituremaker, these mostly eastern hardwoods are most familiar to the public. Humboldt County woodworkers use these woods to make the finest handmade furniture.

MapleHard rock maple is one of the hardest of domestic woods. The "select white" grade of maple has a warm gold-ivory color when finished with a hand rubbed oil. Because of its hardness rock maple is suitable for all types of furniture and cabinetry.

CherryFurniture grade cherry is a moderately heavy, hard, strong, wood. Close grained, it can be polished to a deep and glowing red. Many of the finest early American table tops and interior panels were made of cherrywood. This wood is suitable for all furniture and cabinetry including chairs.

WalnutNorth American walnut is one of the most prized hardwoods. It can range in color from deep rich brown to an almost purple brown. This is an open-pored wood that is relatively hard. Walnut is durable and finishes beautifully. The wood is useful in many furniture applications.

Exotic WoodsAndiroba, Bayo, Bloodwood, Bocote, Bubinga, Spanish Cedar, Chaktekok, Chechen, Chicozapote, Cocobolo, Ebony, Fishtail Oak, Granadillo, Ironbark, Ipe, Jabin, Jarrah, Jatoba, Katalox, Kingwood, Koa, Lacewood, Lignum Vitae, African Mahogany, Machiche, Narra, Obeche, Pau Ferro, African Paduak, Peruvian Walnut, Purpleheart, Brazilian Rosewood, Satinwood, Snakewood, Teak, Vesi Wenge, Zebrawood

With bright colors and expressive grain patterns these woods are often used as highlights in furnishing and turnings. Also, some of these exotic woods such as African mahogany and granadillo are excellent for building whole pieces of furniture, chairs and cabinetry.

LacewoodA relatively soft wood grown widely in Australia, lacewood has an unusual grain structure that has the look of hammered copper when properly cut. It can be used as an accent wood or in veneered tabletops.

GranadilloA beautiful, very hard wood from Southern Mexico with a tan-deep brown streaking. This close grained wood is a "Smart Wood" selectively harvested in cooperation with the indigenous people. This wood is suitable for all furniture applications.

African MahoganyHere is traditional mahogany, deep rich, red and suitable for any furniture application. This wood is imported from Ghana, which has had a sustained yield forestry program in place since 1910.

Common nameBinomial nomenclatureColourDensityLocationCharacteristics, Usage and Status

Aini or AangiliArtocarpus hirsutusYellowish brown595 kg/mMaharashtra,Andhra Pradesh,Tamil Nadu,Karnataka,KeralaElastic, close-grained, and strong. It takespolish. It can be usedunderwater. It is used for ordinary building construction, structural work,paving,furnitureand so forth.

ArjunTerminalia arjunaTerminalia ellipticaDark brown870 kg/mCentral IndiaIt is heavy and strong. It has such uses asbeams,rafters, and posts.

AxlewoodAnogeissus latifolia930 kg/mAndhra Pradesh, Tamil Nadu, Maharashtra,Madhya Pradesh,Bihar,Uttar PradeshIt is very strong, hard and tough. It takes a smooth finish. It is subject to cracking.

BabulAcacia niloticasubsp.indicaWhitish red835 kg/mRajasthan, Andhra Pradesh, Maharashtra, Madhya Pradesh, Tamil Nadu, Karnataka,Bengal,Gujarat, Uttar PradeshIt is strong, hard and tough and it takes up a good polish. It is used for such products as bodies andwheelsofbullock cart, agricultural instruments, tool handles, and well curbs.

BakulMimusops elengiMimusops parvifolia[2]Reddish brown880 kg/mSome parts of North IndiaIt is close-grained and tough. It is used for makingcabinets.

BambooFamilyPoaceae, tribe BambuseaeThroughout India, especiallyAssamand BengalNot actually a tree, but a woody grass, it is flexible, very strong and durable. It is used forscaffoldings, thatched roofs, rafters, temporary bridges, and so forth.

BanyanFicus benghalensisBrown580 kg/mThroughout IndiaIt is strong and durable only under water. The aerial roots are utilized for such items as tent poles and well curbs.

BenteakLagerstoemia parviflora675 kg/mKerala, Madras, Maharashtra, KarnatakaIt is strong and takes up a smooth surface. It may be used for building constructions,boat buildingand furniture.

BijasalPterocarpus marsupiumLight brown800 kg/mKarnataka, Andhra Pradesh, Madhya Pradesh, Maharashtra, Kerala, Uttar Pradesh, Tamil Nadu,OrissaIt is coarse-grained, durable and strong but difficult to work. Termites (also known as white ant) do not easily attack it. It is used for ordinary building construction and forcartwheels.Vulnerable

CasuarinaCasuarinaspp.Reddish brown765 kg/mAndhra Pradesh, Tamil NaduIt grows straight. It is strong and fibrous. It is, however, badly twisted. It is often used for scaffolding and posts for temporary structures.

CoconutCocos nuciferaReddish brownThroughout coastal IndiaTakes polish. Requires preservative treatment. Used as poles, piles, furniture and as formwork in concrete construction.

DeodarCedrus deodaraYellowish brown560 kg/mHimalayas,Punjab, Uttar PradeshDeodar is the most important timber tree providing soft wood. It can be easily worked and it is moderately strong. It possesses distinct annual rings. It is used for making cheap furniture, railway carriages, railway sleepers, packing boxes, structural work and so forth.

GumarGymnema sylvestrePale yellow580 kg/mCentral India,South IndiaIt can be easily worked and is strong and durable especially when used under water. It is used for such products as furniture, carriage, well curbs,yokes, and door panels.

HopeaHopea parvifloraLight to deep brown1010 kg/mMadras, KeralaHopea is extremely strong and tough. It is difficult to work. However, it can be seasoned easily and it is durable and not likely to be damaged by white ants. It has been variously used for ordinary house construction, railway sleepers,piles, and boat building.Endangered

Himalayan Elm, Indian ElmUlmus wallichianaRed960 kg/mThroughout IndiaIt is moderately hard and strong. It is used for door and window frames, carts, and so forth.

Ironwood, Penaga Lilin,Bosneak, Gangaw, MesuaMesua ferreaReddish brown960-1060 kg/mIronwood is durable though it is very hard and is not easily worked. It even resists penetration of nails. It is used for ordinary house construction, bridges, piles, agricultural instruments, railway wagons, and railway sleepers.

Irul, PyinkadoXylia xylocarpa830-1060 kg/mKarnataka, Kerala, Andhra Pradesh, Maharashtra, Orissa, Tamil NaduIt is very hard, heavy and durable. Difficult to work, it also requires slow and careful seasoning. It is used for railway sleepers, agricultural instruments, paving blocks, and heavy construction.Least concern

JackMangifera caesia.Yellow, darkens with age595 kg/mKarnataka, Maharashtra, Tamil Nadu, KeralaIt is compact and even grained. It is moderately strong and easy to work. It takes a good finish and maintains its shape well. It has many uses including plain furniture, boat construction, well curbs, door panels, cabinet making and musical instruments.

JarulLagerstroemiaflos-reginaeLight reddish gray640 kg/mAssam, Bengal, MaharashtraHard and durable, it can be easily worked. It takes a good finish and is used for house construction, boat building, railway carriages, cart making and scaffolding.

Kathal, Keledang, JackfruitArtocarpus heterophyllusYellow to deep brown800 kg/mKarnataka, Andhra Pradesh, Kerala, Maharashtra, Tamil NaduIt is heavy and hard. It is durable under water and in damp conditions, however, it cracks if exposed to direct sun. White ants do not attack it. It is used for piles, platforms of wooden bridges, door and window panels.

Lauraceae, SajLauraceaeDark brown880 kg/mKarnataka, Andhra Pradesh, Bihar, Orissa, Madhya Pradesh, Kerala, Tamil NaduIt is strong, hard and tough. It is subject to cracking and attack by dry rot. White ants do not attack it. It takes a smooth finish. It is used for such purposes as house construction, boat construction, railway sleepers and structural work.

MahoganySwieteniaspp.Reddish brown720 kg/mIt takes a good polish and is easily worked. It is durable under water. It is most commonly used for furniture, pattern making and cabinet work.

MangoMangiferaspp.Deep gray560-720 kg/mThroughout IndiaThe mango tree is well known for its fruits. It is easy to work and it maintains its shape well. It is moderately strong. It is most often used for cheap furniture, toys, packing boxes, cabinet work, panels for doors and for windows.

MulberryMorusspp.Brown650 kg/mPunjabIt is strong, tough and elastic. It takes up a clean finish. It can be well seasoned. It is turned and carved easily. Mulberry is typically used for baskets and sports goods likehockey sticks,tennis racketsandcricket bats.

OakQuercusspp.Yellowish brown865 kg/mOak is strong and durable, with straight silvery grain. It is used for preparing sporting goods.

PalmArecaceaeDark brown1040 kg/mThroughout IndiaIt contains ripe wood in the outer crust. The colour of this ripened wood is dark brown. It is strong, durable and fibrous. Palm is used for furniture, roof covering, rafters and joists.

PinePinusspp.Pine wood is hard and tough except white pine which is soft. It decays easily if it comes into contact with soil. It is heavy and coarse grained. It is used for pattern making, frames for doors and windows, and for paving material. White pine is light and straight grained and is used in the manufacture ofmatches.

Red cedarRed480 kg/mAssam, NagpurIt is soft and even grained. It is used for furniture, door panels and well curbs.

RosewoodDalbergia latifoliaDark850 kg/mKerala, Karnataka, Maharashtra, Madhya Pradesh, Tamil Nadu, OrrissaIt is strong, tough and close-grained. It is a handsome wood that takes up a high polish. It maintains its shape well and is available in large sizes. It is used for furniture of superior quality, cabinet work, ornamental carvings and so forth.Vulnerable

SalShorea robustaBrown880-1050 kg/mKarnataka, Andhra Pradesh, Maharashtra, Uttar Pradesh, Bihar, Madhya Pradesh, OrissaIt is hard, fibrous and close-grained. It does not take up a good polish. It requires slow and careful seasoning. It is durable under ground and water. It is used for railway sleepers,shipbuilding, and bridges.

SandalwoodSantalumspp.White or Red930 kg/mKarnataka, Tamil Nadu, Kerala, Assam, Nagpur, BengalIt has a pleasant smell. It is commonly used for agricultural instruments, well curbs, wheels, and mallets.Vulnerable

SatinwoodChloroxylon swieteniaYellow960 kg/mCentral and Southern IndiaIt is very hard and durable. It is close grained. It is used for furniture and other ornamental works.Vulnerable

SimulBombaxspp.White450 kg/mAll over IndiaIt is a loose grained, inferior quality wood. Light in weight, it is used for packing cases, the match industry, well curbs, and for cheap furniture.

SirisAlbiziaspp.Dark brownNorth IndiaHard and durable, Siris wood is difficult to work. It is used for well curbs in salty water, beams, posts, and furniture.

SissooDalbergia sissooDark brown770 kg/mMysore, Maharashtra, Assam, Bengal, Uttar Pradesh, OrissaAlso known asshishamortali, this wood is strong and tough. It is durable and handsome and it maintains its shape well. It can be easily seasoned. It is difficult to work but it takes a fine polish. It is used for high quality furniture,plywoods, bridge piles, sport goods, railway sleepers and so forth. It is a very good material for decorative works andcarvings.

SprucePiceaspp.480 kg/mSpruce wood resists decay and is not affected by the attack of marine borers. It is however liable to shrink, twist and warp. It is used for piles under water and (formerly) for aeroplane construction.

SundriHeritiera fomesDark red960 kg/mBengalIt is hard and tough. It is difficult to season and work. It is elastic and close grained. It is strong and durable. These qualities make it suited for such uses as boat building, piles, poles, tool handles, and carriage shafts.

TamarindTamarindus indicaDark brown1280 kg/mAll over IndiaTamarind is knotty and durable. It is a beautiful tree for avenue and gardens. Its development is very slow but it ultimately forms a massive appearance. Its fruit is also very useful. It is used for agricultural instruments, well curbs, sugar mills, carts and brick burning.

TeakTectona grandisDeep yellow to dark brown639 kg/mCentral India and Southern IndiaModerately hard, teak is durable and fire-resistant. It can be easily seasoned and worked. It takes up a good polish and is not attacked by white ants and dry rot. It does not corrode iron fastenings and it shrinks little. It is among the most valuable timber trees of the world and its use is limited to superior work only.

Toon, Red CedarToona ciliataReddish brown or dull red450 kg/mAssamIt can be easily worked. It is light in weight. It is used for such products as furniture, packing boxes, cabinet making and door panels.

WOOD-ALL OVER THE WORLDSpecies/Timber type/DensityTextureMoistureWorkingDurabilityTreatabilityAvailability/RemarksUses

OriginColourkg/m3movementqualitiesFungiHeartwoodPrice

AburaHardwoodMedium/ModeratelyLimitedColour variable. Resistant toInterior joinery,

Hallea ciliata580*SmallMediumNot durable

Light brownfineeasyLowacidsmouldings

W Africa

AfrormosiaHardwoodMedium/Durable - veryExtremelyDarkens on exposure. Stains inInterior and exterior

Pericopsis elata710SmallMediumCITES IIcontact with iron in dampjoinery. Furniture.

Light brownfinedurableDifficult

W AfricaconditionsCladding

Afzelia (doussi)HardwoodMedium/Medium/ExtremelyLimitedExudes yellow dye in dampInterior and exterior

Afzelia spp830*SmallVery durable

Reddish-browncoarsedifficultdifficultMediumconditionsjoinery. Cladding

W Africa

AgbaModerately

GossweilerodendronHardwoodLimitedGum exudation may beInterior and exterior

510MediumSmallGooddurable -Difficult

balsamiferumYellowish-brownMediumtroublesomejoinery, trim. Cladding

durable

W Africa

AndirobaHardwoodMedium/Slightly durableLimited

Carapa guianensis640SmallMedium- moderatelyDifficultInterior joinery

Pink to red-browncoarseMedium

S Americadurable

Ash, AmericanHardwoodRegularInterior joinery, trim.

Fraxinus spp670*CoarseMediumMediumNot durableEasy

Grey, brownMediumTool handles

USA

Ash, EuropeanHardwoodMedium/ModeratelyRegularSelected stock may be toughInterior joinery. Sports

Fraxinus excelsior710*MediumGoodNot durable

White to light browncoarseeasyMediumand suitable for bendinggoods

Europe

Aspen (American,Hardwood

Canadian)ExtremelyVariable

Grey, white to pale450FineLargeMediumNot durableInterior joinery. Matches

Populus tremuloidesdifficult **Low

brown

Canada, USA

BalsaHardwoodLimitedHigh buoyancy value. GoodHeat, sound and

Ochroma lagopus160*FineSmallGoodNot durableDifficult

WhiteMediuminsulating valuevibration insulation

S America

Balau (yellow)HardwoodExtremelyVariableA hard, heavy, strong timber.Heavy structural work,

Shorea sppYellow-brown to980*MediumMediumMediumDurablebridge and wharf

difficultLowObtainable in large sizes

S E Asiared-brownconstruction

BasswoodHardwoodLimitedConstructional veneer.

Tilia americanaCreamy white to420FineMediumGoodNot durableEasyTurnery, piano keys,

Medium

N Americapale brownwoodware

Beech, EuropeanHardwoodEasyFurniture, interior

Whitish to pale(red heartRegular

Fagus sylvatica720FineLargeGoodNot durableExcellent bending propertiesjoinery, flooring.

brown, pinkish-red ifextremelyLow/Medium

Europesteameddifficult)Plywood

Species/Timber type/DensityTextureMoistureWorkingDurabilityTreatabilityAvailability/Remarks


Birch, AmericanHardwoodEasy -RegularIncludes yellow birch andFurniture. Plywood.

Betula sppLight to dark reddish640/710FineLargeGoodNot durablemoderately

Lowpaper birchFlooring

North Americabrowneasy

Birch, EuropeanHardwoodEasy -LimitedIncludes silver birch and whitePlywood. Furniture.

Betula pendula, B. pubescens670FineLargeGoodNot durablemoderately

White to light brownLowbirchTurnery

Europeeasy

Cedar of LebanonSoftwoodMedium/LimitedJoinery. Garden

Cedrus libani580MediumGoodDurableDifficultPungent cedar odour

Light brownsmall **Lowfurniture. Gates

Europe

Cedar, Central/SHardwoodCabinet work, interior

AmericanExtremelyLimited

Pinkish-brown to480CoarseSmallGoodDurableDistinctive odourjoinery. Racing boat

Cedrela sppdifficultMedium

dark reddish-brownbuilding. Cigar boxes

Central & S America

Cherry, AmericanHardwoodModeratelyLimitedCabinet making,

Prunus serotinaReddish-brown to580FineMediumGoodNo information

durableMediumfurniture, interior joinery

USAred

Cherry, EuropeanHardwoodModeratelyLimitedInclined to warp; use in smallCabinet making,

Prunus avium630FineMediumGoodNo information

PInkish-browndurableMedium/Highsectionsfurniture

Europe

Chestnut, horseHardwoodLimitedBrush backs. Fruit trays

Aesculus hippocastanumWhite to pale510FineSmallMediumNot durableEasy

Lowand boxes

Europeyellow-brown

Chestnut, sweetHardwoodExtremelyLimitedStains in contact with iron inInterior and exterior

Castanea sativa560MediumLargeGoodDurable

Yellowish-browndifficultMediumdamp conditionsjoinery. Fencing

Europe

DantaHardwoodModeratelyDifficult -LimitedFlooring. Joinery.

Nesogordonia papaverifera750FineMediumGoodextremely

Reddish-browndurableLowTurnery

W Africadifficult

Douglas firModeratelyMarked flame-like growth ringPlywood. Interior and

Pseudotsuga menziesiiSoftwood530MediumSmallGooddurable -ExtremelyRegularfigure. Long lengths and clearexterior joinery.

N America & UKLight reddish-browndifficultMediumConstruction. Vats &

durablegrades available

tanks

EbonyHardwood1030/ExtremelyLimitedGenerally small sizes onlyUsed primarily for

Diospyros sppBlack, someFineMediumMediumVery durabledecorative work.

1190difficultHighavailable. Dust may be irritant

W Africa, India, Sri Lankagrey/black stripesTurnery, inlaying

Ekki/azobHardwoodDurableExtremelyLimitedModerately resistant to termiteHeavy construction;

Lophira alataDark red to dark1070CoarseLargeDifficultattack. Acid resistant.marine and freshwater.

(variable)difficultLow/Medium

W AfricabrownObtainable in large sizesBridges, sleepers, etc

Elm, EuropeanHardwoodModeratelyLimitedIncludes smooth leaved elm,Furniture, coffins. Boat

Ulmus spp560*CoarseMediumMediumSlightly durable

EuropeLight browneasy - DifficultMediumwych elmbuilding

Species/Timber type/DensityTextureMoistureWorkingDurabilityTreatabilityAvailability/RemarksUses


Elm, WhiteHardwoodLimitedGood strength, toughness andFurniture. Coffins.

Ulmus americana580CoarseMediumMediumSlightly durableDifficult

Pale reddish-brownMediumbending propertiesRubbing strips

N America

GaboonHardwoodLimitedUsed principally for

Aucoumea klaineana430MediumMediumMediumSlightly durableDifficult

Pinkish brownMediumplywood and blockboard

W Africa

Gedu nohor/edinamHardwoodModeratelyExtremelyLimitedFurniture, interior and

Entandrophragma angolense560MediumSmallMedium

Reddish browndurabledifficultLow/Mediumexterior joinery

W Africa

GeronggangHardwoodVariable

Cratoxylon arborescens540CoarseMediumMediumSlightly durableEasyInterior joinery

Pink to redLow

S E Asia

GreeenheartHardwoodExtremelyVariableHeavy construction;

Ocotea rodiaeiYellow/olive green to1040FineMediumDifficultVery durableAvailable in very large sizesmarine and freshwater.

difficultMedium

Guyanabrownbridges, etc

GuareaHardwoodDurableExtremelyVariableFine dust may be irritant.Furniture, interior

Guarea cedrata590MediumSmallMedium

Pinkish brown(variable)difficultLow/MediumResin exudation may occurjoinery, cabinet making

W Africa

Hemlock, WesternSoftwoodModeratelyRegularObtainable in large sizes, long

Tsuga heterophylla500FineSmallGoodSlightly durableConstruction. Joinery

N AmericaPale browneasy - DifficultLow/Mediumlengths and clear grades

Hevea - see Rubberwood

HickoryHardwoodModeratelyLimitedGood steam bendingStriking tool handles.

Carya sppBrown to830CoarseLargeDifficultSlightly durableproperties. Good shockLadder rungs. Sports

easyMedium

N America (Eastern)reddish-brownresistancegoods

IdigboModeratelyStains yellow in contact with

Terminalia ivorensisHardwoodExtremelyVariablewater; stains in contact withInterior and exterior

560*MediumSmallMediumdurable /

W AfricaYellowdifficultMediumiron when wet. Acidic and mayjoinery. Plywood

Durable

corrode ferrous metals.

IrokoHardwoodMedium/Durable /ExtremelyRegularOccasional deposits of stoneExterior and interior

Milicia excelsa, M. regia660MediumSmalljoinery. Bench tops.

Yellow-browndifficultVery durabledifficultLow/Mediummay occur

W AfricaConstructional work

JarrahHardwoodExtremelyLimitedHeavy constructional

Eucalyptus marginata820*MediumMediumDifficultVery durable

Pink to dark reddifficultLow/mediumwork. Flooring

Australia

JelutongHardwoodRegularPattern making. Drawing

Dyera costulata470FineSmallGoodSlightly durableEasyLatex ducts may be present

White to yellowMediumboards

S E Asia

KapurHardwoodDurable / VeryExtremelyVariableExterior joinery.

Dryobalanops spp770*MediumMediumMediumCamphor-like odourDecking. constructional

Reddish-browndurabledifficultMedium

S E Asiause



KarriHardwoodExtremelyLimited

Eucalyptus diversicolor900MediumLargeDifficultDurableHeavy construction

Reddish-browndifficultMedium

Australia

KempasHardwoodLimitedSlightly acidic and may

Koompassia malaccensisOrange-red to880CoarseMediumDifficultDurableDifficultencourage corrosion of ferrousHeavy constructional use

Low

S E Asiared-brownmetals

Keruing, apitong, gurjun,HardwoodModeratelyHeavy and general

yangPinkish-brown to740*MediumLarge/DifficultdurableDifficultRegularLiable to resin exudationconstruction. Decking,

Dipterocarpus sppMedium(variable)Low

dark brown(variable))vehicle flooring

S E Asia

Larch, EuropeanSoftwoodSlightly durableExtremelyRegularBoat planking.

Larix deciduaPale reddish-brown550FineSmallMedium/ ModeratelydifficultLowTransmission poles

Europedurable

Larch, JapaneseSoftwoodSlightly durableExtremelyRegularStakes. General

Larix kaempferiReddish-brown530FineSmallMedium/ ModeratelydifficultMediumconstruction

Europedurable

Lauan - see Meranti

Lignum vitaeHardwoodExtremelyCITES IIBushes and bearings.

Guaiacum spp1250FineMediumDifficultVery durableObtainable in small sizes only

Dark green/browndifficultHighSports goods

Central America

Limba/afaraHardwoodModeratelyLimitedFurniture. Interior

Terminalia superbaPale yellow,560*MediumSmallGoodSlightly durable

W Africabrown/straweasyLow/mediumjoinery

Lime, EuropeanHardwoodLimited/Carving, turnery. Bungs.

Tilia sppYellowish-white to560FineMediumGoodNot durableEasy

LowClogs

Europepale brown

Mahogany, AfricanHardwoodModeratelyExtremelyRegularFurniture, cabinet work.

Khaya spp530*MediumSmallMedium

Reddish-browndurabledifficultLow/MediumBoat building. Joinery

W Africa

Mahogany, AmericanHardwoodExtremelyCITES IIIFurniture, cabinet work.

Swietenia macrophylla560*MediumSmallGoodDurableRegularInterior and exterior

Reddish-browndifficult

Central & S AmericaHighjoinery. Boat building

MakorHardwoodFurniture. Interior and

Tieghemella heckelii,ExtremelyVariable

Pinkish-brown to640FineSmallMediumVery durableFine dust may be irritantexterior joinery. Boat

T. africanadifficultMedium

dark redbuilding. Plywood

W Africa

Maple, rockHardwoodRegularExcellent flooring timber.

Acer saccharum, A. nigrum740FineMediumMediumSlightly durableDifficultHigh resistance to abrasion

Creamy whiteMediumFurniture. Sports goods

N America



Maple, soft

Acer saccharinum,Hardwood550*FineMediumMediumSlightly durableModeratelyLimitedFurniture. Interior

A. rubrumCreamy whiteeasyMediumjoinery. Turnery

N America

MengkulangHardwoodLimitedInterior joinery.

Heritiera spp720CoarseSmallMediumSlightly durableDifficult

Red, brownMediumConstruction. Plywood

S E Asia

Meranti, dark red/darkHardwoodSlightly durableExtremely

red seraya/red lauanRegularInterior and exterior

Medium to dark710*MediumSmallMedium- durabledifficult

Shorea sppLow/Mediumjoinery. Plywood

red-brown(variable)(variable)

S E Asia

Meranti, light red/lightSlightly durableExtremely

red seraya/white lauanHardwoodRegular

550*MediumSmallMedium/ ModeratelydifficultInterior joinery. Plywood

Shorea sppPale pink to mid redLow

durable(variable)

S E Asia

Meranti, yellow/Extremely

yellow serayaHardwoodLimited

660*MediumSmallMediumSlightly durabledifficultInterior joinery. Plywood

Shorea sppYellow-brownLow/Medium

(variable)

S E Asia

MerbauHardwoodDurable / VeryExtremelyVariableLiable to stain in contact withJoinery. Flooring.

Intsia bijuga, I. palembanicaMedium brown to830CoarseSmallModerate

durabledifficultMediumiron in damp conditionsStructural work

S E Asiadark red-brown

NiangonHardwoodModeratelyExtremelyVariableInterior and exterior

Heritiera utilis, H. densiflora640*MediumMediumGood

W AfricaReddish browndurabledifficultLowjoinery. Furniture

NyatohHardwoodSlightly durableExtremelyVariableFurniture. Interior

Palaquium sppPale pink to720*FineMediumMedium/ ModeratelydifficultLowjoinery.

S E Asiared-browndurable

Oak, American redHardwoodModeratelyRegularFurniture. Interior

Quercus sppYellowish-brown790MediumMediumMediumSlightly durable

easy/ DifficultMediumjoinery

N Americawith red tinge

Oak, American whiteHardwoodModeratelyAcidic nature; iron staining mayFurniture, cabinet work.

Quercus sppPale yellow to770MediumMediumMediumdurable /ExtremelyRegularoccur in damp conditions. MayInterior and exterior

N AmericadifficultMediumjoinery. Flooring. Tight

mid-brownDurablealso corrode metals

cooperage

Oak, EuropeanIron staining may occur inFurniture. Interior and

Quercus robur, Q. petraeaHardwoodMedium/Medium/ExtremelyVariableexterior joinery.

720*MediumDurabledamp conditions, similarly

EuropeYellowish-browncoarsedifficultdifficultMedium/HighFlooring. Tight

corrosion of metals

cooperage. Fencing



Oak, JapaneseHardwoodModeratelyExtremelyVery limitedFurniture. Interior

Quercus mongolica (mainly)670MediumMediumMedium

Pale yellowdurabledifficult**Highjoinery

Japan

Oak, Tasmanian

Eucalyptus delegatensisHardwood610/CoarseMediumMediumModeratelyDifficultLimitedFurniture. Interior

E obliqua, E regnansPale pink to brown710*durableMediumjoinery

Australia & Tasmania

Obeche /wawaHardwoodRegularInterior joinery.

Triplochiton scleroxylon390MediumSmallGoodNot durableDifficult

White to pale yellowLow/MediumFurniture. Plywood

W Africa

OpepeHardwoodHeavy construction.

Nauclea diderrichiiModeratelyVariableMarine and freshwater

Yellow to750CoarseSmallMediumVery durable

W AfricaeasyLowuse. Exterior joinery.

orange-yellow

Flooring

PadaukHardwoodInterior and exterior

Pterocarpus spp740*/ModeratelyLimited

Red to darkCoarseSmallMediumVery durableDust may be irritantjoinery. Turnery.

W Africa, Andamans,850easyHigh

purple-brownFlooring

Myanmar

Parana pineSoftwoodNot durable -ModeratelyRegular

Araucaria angustifoliaGolden brown with550FineMediumGoodDistortion may occur in dryingInterior joinery. Plywood

Slightly durableeasyLow/Medium

S Americabright red streaks

Pine, Canadian redSoftwoodModeratelyLimited

Pinus resinosaReddish yellow,450FineSmallGoodSlightly durableConstruction. Joinery

easyLow

N Americawhite

Pine, CorsicanSoftwoodSlightly durableExtremelyRegularJoinery, construction

Pinus nigra var maritimaLight yellowish-510CoarseSmallMedium(variable)difficultLow

Europebrown(variable)

Pine, elliotis

Pinus elliottiiSoftwood590MediumMediumMediumSlightly durableModeratelyRegularPallets, packaging.

Brazil, Chile (PlantationPale brown to yelloweasyLowJoinery

grown)

Pine, JackSoftwoodModeratelyVariable

Pinus banksianaPale brown/ reddish500MediumMediumMediumSlightly durableConstruction, joinery

easyLow

Canada, USAbrown

Pine, lodgepoleSoftwoodSlightly durableDifficult -

Pinus contortaYellow to paleRegular

470FineSmallGood- ModeratelyExtremelyConstruction. Joinery

N Americabrown tinged withLow

durabledifficult

red

Pine, maritimeSoftwoodMedium-Slightly durableRegularPallets and packaging.

Pinus pinaster530MediumGood- ModeratelyDifficult

Pale brown to yellowCoarseLowJoinery

Europedurable



Pine, patulaSoftwoodModeratelyLimitedPallets and packaging.

Pinus patula590MediumMediumMediumSlightly durable

Pale brown to yelloweasyLowJoinery

South Africa

Pine, pitch, AmericanSoftwoodSlightly durableDifficult -RegularDenser material also known asInterior and exterior

Pinus palustris, P. elliottiiYellow-brown to670*MediumMediumMedium- ModeratelyExtremelylongleaf yellow pine or longleafjoinery. Heavy

Medium

Southern USAred-browndurabledifficultpitch pineconstruction

Pine, ponderosaSoftwoodModeratelyVariable

Pinus ponderosaPale to dark yellow480FineSmallGoodSlightly durableConstruction. Joinery

easyLow

N Americato reddish-brown

Pine, radiataSoftwood

Pinus radiataNot durable -ModeratelyRegularConstruction, furniture,

Yellow to pale480MediumMediumGood

S Africa, S America,Slightly durableeasy - DifficultLowpackaging

brown

Australia, New Zealand

Pine, ScotsSoftwoodSlightly durableDifficult -Regular

Pinus sylvestrisPale yellowish-510CoarseMediumMedium- ModeratelyExtremelyConstruction, joinery

Low

UKbrown to red-browndurabledifficult

Pine, SouthernSlightly

Pinus spp including P.SoftwoodDifficult -

durable/RegularAlso know as Southern yellowConstruction, joinery.

palustris, P. elliottii, P.Pale yellow to light590MediumMediumMediumExtremely

ModeratelyLowpinePlywood

echinata, P. taedabrowndifficult

durable

Southern USA

Pine, yellowSoftwoodModeratelyRegularAlso known as Quebec yellowPattern making, drawing

Pinus strobusPale yellow to light420FineSmallGoodSlightly durable

easyLow/mediumpine and Eastern white pineboards, doors

N Americabrown

Plane, EuropeanHardwoodNoLimitedQuarter sawn materialDecorative purposes.

Platanus x hispanica640FineMediumNot durableNo information

Mottled browninformationMediumproduces lacewood figureInlay work

Europe

PoplarHardwoodFine/DifficultVariablePallet blocks, box

Populus sppGrey white to pale450LargeMediumNot durableboards, turnery. Wood

Medium(variable)Low

Europebrownwool

Poplar, American yellowsee Tulipwood

PurpleheartHardwoodMedium/ModeratelyExtremelyLimitedHeavy construction.

Peltogyne sppPurple to880MediumSmalldurable -

DifficultdifficultHighFlooring. Turnery

Central & S Americapurplish-brownDurable

RaminHardwoodVariable

Gonystylus spp670MediumLargeMediumNot durableEasyMouldings. Furniture

White to pale yellowLow/Medium

S E Asia

Redwood, EuropeanSoftwoodSlightly durableDifficult -Regular

Pinus sylvestrisPale yellowish-510MediumMediumMedium- ModeratelyExtremely

Low

Scandinavia/USSRbrown to red browndurabledifficult

Construction. Joinery.Furniture



RosewoodHardwoodUnlikely to be available as raw

Dalbergia sppMedium to darkExtremelyD nigraInterior joinery. Cabinet

870*MediumSmallMediumVery durablematerial. Fine dust may be

S America, Indiapurplish-brown withdifficultCITES Iwork, turnery

irritant

black streaks

Rubberwood / heveaHardwoodMedium/Medium -Medium/

Hevea brasiliensisCream to light560Not durableEasyLimitedFurniture, Turnery

CoarseLargeGood

Brazil, S E Asiabrown

SapeleHardwood

EntandrophragmaMedium reddish-640MediumMediumMediumModeratelyDifficultRegularInterior joinery.

cylindricumbrown with markeddurableMediumFurniture. Flooring

West Africastripe figure

SepetirHardwoodExtremelyLimited

Sindora spp680MediumSmallDifficultDurableJoinery. Furniture

Golden browndifficultLow

S E Asia

Seraya- see Meranti

SesendokHardwoodMediumLimitedMouldings, interior

Endospermum sppPale cream to straw480SmallMediumNot durableEasyAlso known as Kauvula (Fiji)

to coarseLow/mediumjoinery

S E Asiayellow

Spruce, CanadianSoftwood400*/Not durable -Regular

Picea sppMediumSmallGoodDifficultConstruction.

White to pale yellow500Slightly durableLow

Canada

Spruce, SitkaSoftwoodNot durable -RegularConstruction. Packaging,

Picea sitchensis450CoarseSmallGoodDifficult

Pinkish-brownSlightly durableLowpallets

North America, UK

SycamoreHardwoodLimited

Acer pseudoplatanusWhite or630FineMediumGoodNot durableEasyTurnery. Joinery

Medium

Europeyellowish-white

TaunHardwoodModeratelyDifficult -LimitedStructural work.

Pometia pinnata720CoarseMediumMediumExtremelyTurnery, joinery,

Pale pinkish-browndurableLow

S E Asiadifficultfurniture

TeakHardwoodFine dust may be irritant. Good

Tectona grandischemical resistance. ResistantFurniture. Interior and

Golden brown,ExtremelyRegular

Burma, Thailand660MediumSmallMediumVery durableto termites. Some cultivatedexterior joinery. Boat

sometimes with darkdifficultHigh

and plantations elsewheremarkingstimber may have lowerbuilding

durability

Tulipwood /Poplar,Hardwood

American yellowYellowish to olive510FineMediumGoodSlightly durableNo informationLimitedJoinery, Furniture

Liriodendron tulipiferabrown with darkMedium

N Americastains



UtileHardwoodModeratelyExtremelyRegularInterior and exterior

Entandrophragma utile660MediumMediumMediumdurable -joinery. Furniture and

Reddish-browndifficultMedium

W AfricaDurablecabinet work

Virola, lightEasy -

Virola sppHardwoodLimitedCarpentry, mouldings.

530*MediumMediumMediumNot durableModerately

Dialyanthera sppPale pinkish-brownLowFurniture. Plywood.

easy

Central and S America

WallabaTransmission poles.

Eperua falcata,HardwoodExtremelyLimited

910CoarseMedium**MediumVery durableGum exudation likelyFlooring, Decking. Heavy

E. grandifloraDull reddish-browndifficultMedium

construction

Guyana

Walnut, AfricanHardwoodSlightly durableDifficult -

Lovoa trichilioidesYellowish-brown,VariableFurniture, cabinet work.

560MediumSmallMedium- ModeratelyExtremely

W Africasometimes with darkMediumand exterior joinery

streaksdurabledifficult

Walnut, AmericanHardwoodSmall/ModeratelyDifficult -Variable

Juglans nigra660CoarseGoodExtremelyAlso known as Black walnutFurniture. Gun stocks

Rich dark brownMedium**durableMedium/High

N Americadifficult

Walnut, EuropeanHardwoodModeratelyLimitedStaining likely if in contact withFurniture, turnery. Gun

Juglans regiaGrey-brown with670CoarseMediumGoodDifficult

durableHighiron under damp conditionsstocks

Europedark streaks

Weng / Panga pangaHardwoodInterior and exterior

Millettia laurentiiExtremelyLimited

Dark brown with880*CoarseSmallGoodDurablejoinery. Flooring.

M stuhlmanniidifficultMedium

fine black veiningTurnery

Central & E Africa

Western red cedarFine dust may be irritant. An

Thuja plicataSoftwoodModeratelyDifficult -Regularacidic timber which mayShingles, exterior

N America390CoarseSmallGooddurable -Extremelycorrode metals under dampcladding. Greenhouses,

Reddish-brownMedium

Durabledifficultconditions and cause ironbeehives

staining

Whitewood, American - see Tulipwood

Whitewood, EuropeanSoftwoodDifficult -RegularJoinery. Construction.

Picea abies and Abies albaWhite to pale470MediumMediumGoodSlightly durableExtremely

LowFlooring

Europe, USSRyellowish browndifficult

WillowHardwoodLimitedCricket bats. Boxes,

Salix spp450FineSmallGoodNot durableDifficult

pinkish-whiteMedium/highcrates

Europe

YewSoftwoodSmall/Very LimitedFurniture, turnery.

Taxus baccataOrange-brown to670MediumDifficultDurableDifficult

Medium**HighInterior joinery

Europepurple-brown

CUTTING

A mountain ash (Eucalyptus regnans) being felled. Dated to c. 1884-1917, Australia

TimberjackHarvesterat workLoggingis the cutting, skidding, on-site processing, and loading oftreesorlogsontotrucks[1]orskeleton cars.Inforestry, the term logging is sometimes used in a narrow sense concerning the logistics of moving wood from the stump to somewhere outside the forest, usually asawmillor alumber yard. However, in common usage, the term may be used to indicate a range of forestry or silviculture activities.Illegal loggingrefers to what in forestry might be called timber theft.It can also refer to the harvest, transportation, purchase or sale of timber in violation of laws. The harvesting procedure itself may be illegal, including using corrupt means to gain access to forests; extraction without permission or from a protected area; the cutting of protected species; or the extraction of timber in excess of agreed limits. In common usage what is sometimes called clearcut logging is not is necessarily considered a type of logging but a harvest or silviculture method and is simply calledclearcuttingor block cutting. In the forest products industry logging companies may be referred to as logging contractors.Cutting trees with the highest value and leaving those with lower value, often diseased or malformed trees, is referred to as high grading. It is sometimes called selective logging, and confused with selection cutting, the practice of managing stands by harvesting a proportion of trees. Logging usually refers to above-ground forestry logging. Submerged forests exist on land that has been flooded by damming to createreservoirs. Such trees are logged usingunderwater loggingor by the lowering of the reservoirs in question.Ootsa LakeandWilliston LakeinBritish Columbia,Canada, are notable examples where timber recovery has been needed to remove inundated forests. ClearcuttingClearcutting, or clearfelling, is a harvest method that removes essentially all the standing trees in a selected area. Depending on management objectives, a clearcut may or may not have reserve trees left to attain goals other than regeneration,[7]including wildlife habitat management, mitigation of potential erosion or water quality concerns.Silvicultureobjectives for clearcutting, (for example, healthy regeneration of new trees on the site) and a focus onforestrydistinguish it fromdeforestation. Other methods include Shelterwood cutting, group selective, single selective, seed-tree cutting, patch cut and retention cutting.Logging methods

TheWashington Iron Works Skidderin Nuniong is the only one of its kind in Australia, with donkey engine, spars and cables still rigged for work.The above operations can be carried out by different methods, of which the following three are considered industrial methods:Tree-length loggingTrees are felled and thendelimbedand topped at the stump. The log is then transported to the landing, where it isbuckedand loaded on a truck. This leaves theslash(and the nutrients it contains) in the cut area where it must be further treated if wildland fires are of concern.Full-tree loggingTrees and plants are felled and transported to the roadside with top and limbs intact. The trees are then delimbed, topped, and bucked at the landing. This method requires that slash be treated at the landing. In areas with access to cogeneration facilities, the slash can bechippedand used for the production of clean electricity or heat. Full-tree harvesting also refers to utilization of the entire tree including branches and tops. This technique removes both nutrients and soil cover from the site and so can be harmful to the long term health of the area if no further action is taken, however, depending on the species, many of the limbs are often broken off in handling so the end result may not be as different from tree-length logging as it might seem.

Cut-to-length loggingCut-to-length loggingis the process of felling, delimbing, bucking and sorting (pulpwood, sawlog, etc.) at the stump area, leaving limbs and tops in the forest.Harvestersfell the tree, delimb and buck it, and place the resulting logs in bunks to be brought to the landing by askidderorforwarder. This method is routinely available for trees up to 900 mm in diameter. Harvesters are employed effectively in level to moderately steep terrain. Harvesters are highly computerized to optimize cutting lengt, control harvest area byGPSand utilize price list for each specific logs to archive most economical results during harvesting.SpringboardsThe image at the top of the page illustrates the use of springboards. Loggers cut aspringboard notchinto which they insert the springboard, which is then used as a platform, allowing the logger to stand above obstructions/snow or to cut higher-up where the trunk is narrower.Transporting logs

Timber raftinginJoensuucanalat 2009.Felled logs are then generally transported to a sawmill to be cut intotimber, a paper mill forpaper pulp, or for other purposes like fence posts. There were many methods for moving logs from where they were cut to a rail line of a mill. The cheapest methods of transportation of timber arelog drivingandtimber raftingwhich makes use of a river's current to move floating tree trunks downstream tosawmillsandpaper mills. To help herd the logs to the mill, in 1960 the Alaskan Lumber and Pulp Mill had a specially designed boat that was constructed of 1 1/2 inch steel. In the late 1800s and the first half of the 1900s the most common method was thehigh-wheel loaderwhich was a set of wheels over ten feet tall that the log or logs were strapped beneath. Oxes were first used with thehigh-wheel loaders, but in the 1930s tractors replaces the oxes.In 1960 the largest high wheel loader was built for service in California. Called theBunnyan Buggiethe unit was self propelled and had wheels 24 feet high and a front dozer blade that was 30 feet across and 6 feet high.Log transportation can be challenging and costly since trees are often far from navigable roads.Road buildingand maintenance may be restricted inNational Forestsor other wilderness areas since it can cause erosion inriparian zones. When felled logs sit adjacent to a road, heavy machinery may simply lift logs onto trucks. Most often, special heavy equipment is used to gather the logs from site and move them close to the road to be lifted on trucks.Many methods exist to transport felled logs lying away from roads.Cable logginginvolves ayarderwhich pulls one or several logs along the ground to platform where a truck is waiting. When the terrain is too uneven to pull logs on the ground, askylinecan lift logs off the ground vertically, similar to aski lift.Heli-logging, which uses heavy-lift helicopters to remove cut trees from forests by lifting them on cables attached to a helicopter, may be used when cable logging is not allowed due to environmental concerns or when roads are lacking. It reduces the level of infrastructure required to log in a specific location, reducing the environmental impact of logging.Less mainstream forms of log transport, or methods used previously include horses, oxen, or balloon logging.

SEASONINGSeasoning is the controlled process of reducing the moisture content (MC) of the timber so that it is suitable for the environment and intended use. We need to reduce the MC of timber for the following reasons:_ Every time the MC reduces the timber shrinks especially tangentially._ Consequently it will show fewer tendencies to warp, split or shake._ Seasoned timber although lighter will be stronger and more reliable.The sap in timber is a food for fungi and wood parasites. Remove the sap and the wood will be less attractive to these dangers. For construction grade timber the timber must be below 20% MC to reduce the chances of Dry Rot and other fungi infestations._ Dry well seasoned timber is stronger._ Dry well seasoned timber is easier to work with and consequently safer especially machine working.Timber with higher moisture content is difficult to finish i.e. paint, varnish, etc.There are two main ways of seasoning timber, Natural (Air) and Artificial (Kiln) drying. Both methods require the timber be stacked and separated to allow the full circulation flow of air, etc. around the stack.

Air Seasoning.Air seasoning is the method used with the timber stacked in the open air. It requires the following:Stacked stable and safely with horizontal spacing of at least 25 mm.Vertical spacing achieved by using timber battens (piling sticks) of the same or neutral species.Today some timber yards are using plastics.The piling sticks should be vertically aligned and spaced close enough to prevent bowing say 600 to 1200 mm max centres. Ends of boards sealed by using a suitable sealer or cover to prevent too rapid drying out via the end grain.The stack raised well clear of the ground, vegetation, etc to provide good air circulation and free from rising damp, frost, etc.Over head cover from effects of direct sunlight and driving weather.The details depend on the size, quantity and species of the timber.You cannot however expect to obtain less than 16 - 17% mc in the UK.Further seasoning needs to be done inside, in heated and ventilated buildings.

Kiln Seasoning.

There are two main methods used in artificial seasoning, compartmental, and progressive.Both methods rely on the controlled environment to dry out the timber andrequire the following factors:_ Forced air circulation by using large fans, blowers, etc._ Heat of some form provided by piped steam._ Humidity control provided by steam jets.The amount and duration of air, heat and humidity again depends on species, size, quantity, etc. Schedules are published for the various species to enable operators to select an appropriate drying environment.In the UK they are usually provided by the Kiln Manufacturers and also published in the Handbook of Hardwoods and Handbook of Softwoods (BRE).

Compartmental.

A compartment kiln is a single enclosed container or building, etc. The timber is stacked as described above and the whole stack is seasoned using a programme of settings until the whole stack is reduced to the MC required. Compartment kilns differ from progressive kilns in that the timber is loaded into the kiln and remains in place throughout the drying process. Compartment kilns are usually smaller than progressive kilns, and because of their construction the temperature and humidity conditions within them can be closely controlled.Consequently, they are often used to dry expensive material or woods which are difficult to dry. Circulation may be either forced or natural just as with progressive kilns. Drying conditions cannot be controlled as closely in natural draft compartment kilns, however, as in forced draft kilns, and the rate of drying is also slower. For these reasons kilns built today are of the forced draft type and many of the old natural draft types have been converted.

Progressive.

In the progressive kiln, timber enters at one end and moves progressively through the kiln much as a car moves through a tunnel. Temperature and humidity differentials are maintained throughout the length of the kiln so that the lumber charge is progressively dried as it moves from one end to the other. Progressive kilns may be further subdivided into naturaldraft kilnsin which heated air is allowed to rise through the material by natural convection, andforced draft kilnsin which fans are employed to force the air through the wood. A progressive kiln has the stack on trolleys that progressively travel through chambers that change the conditions as it travels through the varying atmospheres.

Progressive Kiln

The advantage of this system, although much larger, has a continuous flow of seasoned timber coming off line.A number of commercial processes for seasoning of timber are available, the most common of which is kiln-drying. Kiln seasoning accelerates the process of seasoning by using external energy to drive the moisture out. The timber is stacked in much the same way as it is for air drying, and is placed inside a chamber in which the conditions can be varied to give best seasoning results. Air is circulated around the charge (stacked timber) and the temperature and humidity can be varied to give optimum drying. Each species has different cell characteristics and therefore requires different drying schedules. Typically the timber may be in the kiln for a period of between two days to one week.Generally, it is not feasible to kiln-dry structural timber in thicknesses greater than 45 mm, although there are limited amounts of 70 mm thick kiln-dried softwood members in the market place. All untreated structural pine and some commercial hardwoods are seasoned, mostly using kilns that are often heated by sawmill by-products or gas.Plenty of research is continually being done to determine kiln drying schedules for different species. An optimum schedule will remove the moisture as quickly as possible, with the minimum quantity of introduced energy, and giving minimum damage to the dried timber.After kiln seasoning, there is often some damage to cells near the surface of the wood. (All of the moisture passes through those cells.) They have in fact collapsed, but can easily be pumped back up in a reconditioning chamber. This chamber introduces steam for a period and puts some moisture back into the outer cells and removes the effect of seasoning collapse.Hard woods have closed cell structure, so take more time in being seasoned and dried.

Wood as a building material

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