appendix: lumber - nrha · lumber, but most information on western lumber in this training course...

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Appendix: LUMBeR

Chapter 1: Types of Lumber

• Alightcoloredsectioniscalledspringwoodandadarkersectioniscalledsummerwood.Springwoodiswiderthansummerwoodbecauseitisformedinthespringandgrowsfasterandthereforeislessdensethanthesummerwood.

• Asthenumberofannualringsincreases,thosenearestthecenterreceivelessnourishmentandbecomeinactiveusuallychangingtoadarkercolor.Heartwoodandsapwoodmaybeaboutequalinstrength,butheartwoodmaybemoreresistanttorotanddecay.

• Verticle grainiswhenthegrainofthewoodrunsparalleltothewidthofthepiece.

• Flat grainiswhenthegrainrunsperpendicular.

Green sizes oF Lumber• Thestatedsizeoflumberiseitherstatedinitsnominalsize,drysizeorgreensize.Calleditsnominalsize;thisisnot

theactualsizeoflumber.Forexample:anominal(stated)sizemightbe2”x4”,buttheactualsizeis1-1/2”x3-1/2”.

• Thepiecestartedoutapproximately2”x4”,butafterdryingandplaningitissmaller.Howmuchitshrinksdependsonwhetherthelumberhasbeenleftgreen(un-dried)orifit’sbeendriedtoamoisturecontentof19%orless(whichisconsidereddry).

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Inthechartbelow,you’llnoticethegreenlumberisslightlylargerthanthedrylumber.Whenthegreenlumbereventuallydriesout,itwillbeaboutthesamedimensionsasthedrylumber.

NominalSize ActualSize GreenSize

1” 3/4” 25/32”

2” 1-1/2” 1-9/16”

4” 3-1/2” 3-9/16”

6” 5-1/2” 5-5/8”

8” 7-1/4” 7-1/2”

10” 9-1/4” 9-1/2”

12” 11-1/4” 11-1/2”

Common deFeCTs oF soFTwood• Thestatedsizeoflumberiseitherstatedinitsnominalsize,drysizeorgreensize.Calleditsnominalsize;thisisnot

theactualsizeoflumber.Forexample:anominal(stated)sizemightbe2”x4”,buttheactualsizeis1-1/2”x3-1/2”.

• Thepiecestartedoutapproximately2”x4,”butafterdryingandplaningitissmaller.Howmuchitshrinksdependsonwhetherthelumberhasbeenleftgreen(un-dried)orifit’sbeendriedtoamoisturecontentof19%orless(whichisconsidereddry).

• Inthechartbelow,you’llnoticethegreenlumberisslightlylargerthanthedrylumber.Whenthegreenlumbereventuallydriesout,itwillbeaboutthesamedimensionsasthedrylumber.

Somecommonnamesofdefectsforsoftwoodsare:

•Check—Woodseparationalongthelengthofthegrain.

•decay—Rottingofthewoodusuallycausedbyfungiand/ormoisture.

•Knots—Manykindsofknotsclassifiedbysizefrompinknotstolargeknots,thoseover1-1/2”indiameter.

•Pitch—Resinaccumulatedinthewoodcellsmakingapatchyappearance.

•split—Woodseparatedlength-wisecompletelythroughfromonefacetotheother.

•wane—Bark,ornowoodatthecorneroredgeoflumber.

•Therearemorenaturalandmanufactureddefectsthanlistedhere.Themoresevereandfrequent,themoretheyaffectstrength.

•Lumberusedforfinishing,appearanceandnon-structuralpurposescanbewhateverthecustomerissatisfiedwith.Butlumberusedforstructuralpurposesmustmeetstructuralrequirements.Sobuildingcodesrequiregradestampedlumberforthesepurposes.Thislumberisgradedtoanationalstandardreflectingthedefectseverityandfrequency.(Formoreinformation,seenextpop-upwindow.)

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GradinG aGenCies For soFTwoods• Thereareseveralgradingagenciesforsoftwoods,buttheyhaveallvoluntarilyadoptedthesamegradingstandards.A

piecestamped“CONSTRUCTION”byanyagencywillmeetthesamestandards.

• Oneofthelargestlumberproducersassociationsisthewestern wood Products association (wwPa),whichdefinesgradesoflumberproducedinthewesternstates.Thereareotherreputableassociationsgradingwesternlumber,butmostinformationonwesternlumberinthistrainingcoursecomesfromtheWWPA.

• The southern Pine inspection bureau (sPib)definesthegradesofsoftwoodlumberproducedintheSoutheasternUnitedStates.

• The northeastern Lumber manufacturers association (neLma) isthemajorruleswritingassociationintheNortheasternUnitedStates.

• Canadiansoftwoodsaregradedunderthenational Lumber Grades authority (nLGa).

• Remember,alltheseagenciesusethesetofstandards(PS20-99)forgradinglumbersetbytheAmericanLumberStandardsCommittee,whichispartoftheU.S.DepartmentofCommerce.

• Inaddition,somesinglespecieshavetheirownassociationsoflumberproducers.Thebiggestoftheseisprobablythe California redwood association (Cra),whichusesitsRedwoodInspectionService(RIS)tograderedwoodboardsanddimensionlumber.Westernredcedaralsohasitsowngradenames.

• Dependingonyourlocation,youmayuseWesternlumber,Southernpine,Eastern,Canadianlumber,oranycombination,dependingonmarketconditions.

sizinG boardsAboardisgenerallyapieceoflumber1”nominalinthickness(3/4”actual)andanywidth.

Thickness

•Mostboardsare3/4”inactualthickness(1”nominal).

•Someboardsare5/8”or1/2”thick,buttheyareusuallysoldfordrawersides,hobbywork,etc.

•Boardsthickerthan1”nominalarecalled5/4(five-quarter)or6/4.Thesearegradedunderboardgradingrulesandmightbeusedinmakingtrim,cabinetsorstairtreads.

•Boardsthatare5/4areoftensoftwoodsinfinishgrades.

•Technically,boardscanbeasthickas16/4accordingtothegradingrulesforboards.Mostlumberyards,though,don’tcarryanythingthickerthan6/4.

Width

•Boardsaretypically2”andwider.

•Typicalstockforastoreis1”x2”,1”x3”,1”x4”,1”x6”,1”x8”,1”x10”and1”x12”.

•Withthickerboards,itiscommontobuyS2Slumber(surfacedontwosides,notontheedges).Theyareoftenrandomwidths.

Length

•Lengthsforboardsareuniform.

•Sizesstartat6’andgoto24’,andbeyond.

•Typicalstockforastoreisboardsinevenfootlengthsfrom8’to16’.Somemarketswilldemand18’,20’and24’.

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Patterns

•Someboardsareprecutintostandardshapesforusessuchaspaneling,siding,flooringorshiplap,whichisaboardwithnotchededgessoadjoiningpiecesoverlap.

•Standardpatternsareassignedanumberandarecompiledina“StandardProductPattern”bookletpublishedbytheWWPA.

•Storescanorderaspecificpatternfromamillandbeassuredtheywillgetthesameshape.

module 2: dimensional Lumber

dimensionaL Lumber GradinG ThesearethegradingguidelinesestablishedforSouthernPine.Thesegradesaresimilartootherspeciesgradesbuttheyhavemoregradeseparationsavailable.However,mostmillsdonotmanufactureallproductsandmakeallgradeseparations.Thoseproductsandgradesmanufacturedbyrelativelyfewmillsarenotedwithanasterisk.

• select structural: highquality,relativelyfreeofcharacteristicsthatmayimpairstrengthorstiffness.

• *dense select structural: Recommendedforuseswherehighstrength,stiffnessandgoodappearancearerequired.

• no. 1: Provideshighstrength,recommendedforgeneralutilityandconstructionpurposes.

• no. 1 dense: goodappearance,especiallysuitablewhereexposedbecauseofknotlimitations.

• no. 2: AlthoughlessrestrictedthanNo.1,suitableforalltypesofconstruction.

• no. 2 dense: Allowswell-spacedknotsofanyquality.

• no. 3: Assigneddesignvaluesmeetwiderangeofdesignrequirements.Recommendedforgeneralconstructionpurposeswhereappearanceisnotacontrollingfactor.ManypiecesincludedinthisgradewouldqualityasNo.2exceptforasinglelimitingcharacteristic.Provideshighqualityandlowcostconstruction.

• stud: CompositeofNo.3strengthandNo.1nailingedgecharacteristics.

• *no. 3 dense: Recommendedforgeneralconstructionpurposeswhereappearanceisnotacontrollingfactor.ManypiecesincludedinthisgradewouldqualifyasNo.2exceptforasinglelimitingcharacteristic.

• *Construction: Recommendedforgeneralframingpurposes.Goodappearance,strongandserviceable.

• * standard: RecommendedforsameusesasConstructiongradebutallowslargerdefects.

• * utility:Recommendedwhereeconomyisdesired.Excellentforblocking,platesandbracing.

• economy: Usablelengthssuitableforbracing,blocking,bulkheadingandotherutilitypurposeswherestrengthandappearancearenotcontrollingfactors.

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Glossary

S2S: surfaced 2 sides

RGH:rough sawn, as it came off the lumber mill

S4S:surfaced on all four sides

4/4:one inch rough sawn

5/4:one and one quarter inch rough sawn

6/4:one and one half inches rough sawn

8/4:two inches rough sawn

13/16:one inch surfaced

BF:board foot

J1E:jointed (straightened) one edge

SD1-80:sanded one side with 80 grit sandpaper

FAS:first and seconds

FT: foot or feet

IN: inch, inches

JTD:jointed

KD:kiln dried

LBR: lumber

LGR:longer

LGTH:length

LF:linear foot

T&G:tongue and grooved

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module 3: boards

sizinG boards

Aboardisgenerallyapieceoflumber1”nominalinthickness(3/4”actual)andanywidth.

Thickness

•Mostboardsare3/4”inactualthickness(1”nominal).

•Someboardsare5/8”or1/2”thick,buttheyareusuallysoldfordrawersides,hobbywork,etc.

•Boardsthickerthan1”nominalarecalled5/4(five-quarter)or6/4.Thesearegradedunderboardgradingrulesandmightbeusedinmakingtrim,cabinetsorstairtreads.

•Boardsthatare5/4areoftensoftwoodsinfinishgrades.

•Technically,boardscanbeasthickas16/4accordingtothegradingrulesforboards.Mostlumberyards,though,don’tcarryanythingthickerthan6/4.

Width

•Boardsaretypically2”andwider.

•Typicalstockforastoreis1”x2”,1”x3”,1”x4”,1”x6”,1”x8”,1”x10”and1”x12”.

•Withthickerboards,itiscommontobuyS2Slumber(surfacedontwosides,notontheedges).Theyareoftenrandomwidths.

Length

•Lengthsforboardsareuniform.

•Sizesstartat6’andgoto24’,andbeyond.

•Typicalstockforastoreisboardsinevenfootlengthsfrom8’to16’.Somemarketswilldemand18’,20’and24’.

Patterns

•Someboardsareprecutintostandardshapesforusessuchaspaneling,siding,flooringorshiplap,whichisaboardwithnotchededgessoadjoiningpiecesoverlap.

•Standardpatternsareassignedanumberandarecompiledina“StandardProductPattern”bookletpublishedbytheWWPA.

•Storescanorderaspecificpatternfromamillandbeassuredtheywillgetthesameshape.

module 4: decks and Fencing

GradinG oF deCKs and FenCinG

redwood

HearTwood Grades

• Clear all Heart:Normallykiln-dried,well-manufacturedandfreefromdefectsononesurface.Surfacedorsaw-textured.Finestarchitecturalheartwoodgrade.Usedforsiding,paneling,trim,cabinetry,moulding,fascia,soffits,millworkanddecks.

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• Construction Heart:Containsknotsofvaryingsizesandotherslightimperfections.Usuallyunseasoned.Surfacedorrough.Usedfordecks,retainingwalls,fences,stairs,gardenstructuresorotheroutdooruses.

• merchantable Heart:Economicalgrade.SlightlylargerknotsthanConstructiongrades.Holeslimitedtosizeofknots.Allowschecks,somesplitsandsomemanufacturingflaws.Unseasoned,surfacedandrough.Usedforfences,retainingwallsandgardenstructures.

saPwood Grades

• Clear:Containssapwoodandheartwoodinvaryingamounts.Normallykiln-driedwithsomeimperfectionsthatarenotpermittedinClearAllHeart.Surfacedortextured.Usedforsiding,paneling,trim,fascia,moulding,deckingandgardenshelters.

• b Grade:Qualitygradecontainingsapwood,limitedknotsandother.Kiln-driedorunseasoned.Surfacedorsaw-textured.Usedforsiding,paneling,trim,fascia,moulding,deckingandgardenshelters.

• Construction Common:SamegeneralcharacteristicsasConstructionHeartbutpermitssapwoodinvaryingamounts.Unseasonedorseasoned.Surfaced,roughorsaw-textured.Usedunseasonedfordecking,fenceboardsandotherabovegardenuses.Usedseasonedforrusticsidings.

• merchantable:SomecharacteristicsasMerchantableHeartbutcontainssapwoodinvaryingamounts.Unseasonedbutcanbeorderedsurfacedorrough.Useforfenceboards,railingsandotherabove-groundgardenuses.

oTHer Grades

• select Heart:Tight-knottedheartwoodresistanttoinsectsanddecay.Facefreeofsplitsorshake.Usuallyunseasoned,surfacedorrough.Usedfordecking,fenceboards,gardenstructuresandotherabovegroundusesnotrequiringdurability.

• select:Containssapwoodinvaryingamountswithsomeimperfectionsonthebackside.Usuallyunseasoned.Surfacedorrough.Usedfordecking,fenceboards,gardenstructuresandotherabove-groundusesnotrequiringdurability.

• Finger-Jointed:Clearboardsupto24’.Madeofkiln-driedpiecesfinger-jointedandend-glued.Normallysurfacedmixedgrain.Usedforfascia,exteriortrim,exteriorsiding,interiorpaneling,trimandmoulding.

Cedar

FollowingaregradingguidelinespublishedbytheWesternRedCedarLumberAssociationusedtogradecedarwood.

• architect Clear®—Thefinestappearance.Manufacturedwithastrictstandardthatrestrictsnaturalcharacteristics.

• architect Knotty®—Permitsknots,buttheymustbetightandsound.Knottypostsofthebestquality.

• Custom Knotty®—Agoodappearanceforthepricesensitivecustomer.Defectssuchasunsoundknotsarerestricted.

• standard and better—Commonlyusedforfenceconstructionwherestructureismoreimportantthanappearance.Allowsforarangeofnaturalcharacteristics.

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staining

Clear stain:Maintainsthenaturalcolorofthewood.Inadditiontoprotectingagainstnormalwearandtear,aclearstainshouldprotectagainstwaterandUVrays.Aclearstainrequiresfrequentrecoating.

Tinted stain:Onestepremovedfromaclearstain.Theyaddaslightpigmenttothewoodandlastlongerthanaclearstain.

semi-Transparent stain:Addsahintofcolorwhileallowingthegrainandtextureofthewoodtoshowthrough.Notforuseonwoodpreviouslypaintedasolidcolor.Useonlyonwooduntreatedorstainedwithalightershadeofstain.

solid Color stain: Changesthecolorofthewoodwhilestillallowingthegraintoshowthrough.Offerthebestprotectionandareidealforwoodthathasbeguntoshowitsage.Theylastlongerthanothertypesofstains.Canusetocoverpreviouslystainedorpaintedsurfaces.

Here are some additional tips for finishing redwood.

•Waterrepellentwithmildewcideisarecommendednatural,stand-alonefinishandanexcellentbasecoatforpaintorstain.Itreducescheckingandtheeffectsofdirtandweather,resistsmildewandavoidsnaturaldarkening.Withtwocoats,woodgraduallylightenstobuckskintan.

•BleachingOilscontainingmildewcideproducepermanentdriftwoodgray,eliminatingdarkening.Theymaycontainorcanbemixedwithwaterrepellentandgraystain.

•Semi-transparentstainsinlightcolorstonewoodwithouthidinggrainpatterns.Waterrepellentiscontainedin,orcanbemixedwith,theselow-maintenancefinishes.

•Heavy-bodieslatex-basedstainsapplysolidcolorsthatobscurewoodgrainsbuthighlighttextures.Theyshouldbeappliedovercompatibleoil-basedprimer.

•Paintshouldbeappliedovercompatibleoil-basedprimer.Particularlywithsaw-texturedwood,twotopcoatswilllast8-10years.

•Factoryfinishavailableonsomeredwood.Thefinishmaybeawaterrepellent,paintprimerorstain.Canbemoreeconomicalanduniformthanfieldapplications.

maintaining

Herearesometipsyoucangiveyourcustomerswhoneedtoclean,waterproof,striporstaintheirwooddeckorfence

Cleaning

• Keepthesurfacesweptofleavesanddirt.

•Alwayscleandirt,mildewandalgaebeforestaining

•Repairlooseorrottenboardsbeforestaining

•Cleanwithapowerwasher,butlimitthepowerto1,500psi

•Letthecleanersitonthefenceforabout2minutesbeforerisingwaterproofing

• Everywoodsurface,evenifit’spressuretreated,needswaterproofing

•Applywater-basedproductsjusthoursaftercleaningthesurface

•Applyoil-basedproductstoacompletelydrysurface

•Applyonlyonecoat.Multiplecoatswillnotresultinextraprotection.Rather,itwillleaveatackyfinish

•Useproductsthatoffermildew-resistance

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stripping

•Useapowerwasherandbesuretowearprotectiveclothing

•Coverplants,sidewalksandanythingelsethatmightbedamagedbythestrippingsolution

•Useasynthetic,stiffbristlebrush(notawireornaturalbristlebrush)toscruboutstubbornstains

•Afterapplyingthestripper,thoroughlyrinsetocompletelyremovethechemicalresidue

•Letthefencedrythoroughlybeforestaining,usuallyacoupleofdays. staining

• Testasmallareatobesureyouaresatisfiedwiththecolor

•Mixgallonsforuniformityofcolor

•Useanairlesssprayeronthelowestsettingandwithafinemistandusealargeorificetip

•Haveabrushhandytoeliminatepoolsofstain

staining Tips

Clear stain:Maintainsthenaturalcolorofthewood.Inadditiontoprotectingagainstnormalwearandtear,aclearstainshouldprotectagainstwaterandUVrays.Aclearstainrequiresfrequentrecoating.

Tinted stain:Onestepremovedfromaclearstain.Theyaddaslightpigmenttothewoodandlastlongerthanaclearstain.

semi-Transparent stain:Addsahintofcolorwhileallowingthegrainandtextureofthewoodtoshowthrough.Notforuseonwoodpreviouslypaintedasolidcolor.Useonlyonwooduntreatedorstainedwithalightershadeofstain.

solid Color stain.Changesthecolorofthewoodwhilestillallowingthegraintoshowthrough.Offerthebestprotectionandareidealforwoodthathasbeguntoshowitsage.Theylastlongerthanothertypesofstains.Canusetocoverpreviouslystainedorpaintedsurfaces.

Here are some additional tips for finishing redwood.

•Waterrepellentwithmildewcideisarecommendednaturalstandalonefinishandanexcellentbasecoatforpaintorstain.Itreducescheckingandtheeffectsofdirtandweather,resistsmildewandavoidsnaturaldarkening.Withtwocoats,woodgraduallylightenstobuckskintan.

•BleachingOilscontainingmildewcideproducepermanentdriftwoodgray,eliminatingdarkening.Theymaycontainorcanbemixedwithwaterrepellentandgraystain.

•Semi-transparentstainsinlightcolorstonewoodwithouthidinggrainpatterns.Waterrepellentiscontainedin,orcanbemixedwith,theselow-maintenancefinishes.

•Heavy-bodieslatex-basedstainsapplysolidcolorsthatobscurewoodgrainsbuthighlighttextures.Theyshouldbeappliedovercompatibleoil-basedprimer.

•Paintshouldbeappliedovercompatibleoil-basedprimer.Particularlywithsaw-texturedwood,twotopcoatswilllast8-10years. Factoryfinishavailableonsomeredwood.Thefinishmaybeawaterrepellent,paintprimerorstain.Canbemoreeconomicalanduniformthanfieldapplications.

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module 5: Hardwood Lumber

Common CHaraCTerisTiCs oF HardwoodThefollowingarecommoncharacteristicsofhardwoodnotconsidereddefectswhengradingthequalityofaboard.

Quarter sawn

Toquartersawapieceofwoodmeanscuttingthelogata90ºangletothegrowthring.Thiswillproduceauniformorverticalgrainpattern.Thismethodofcuttingproducesfewerboardsperlogandthusquarter-sawnboardsaremoreexpensive.Theyareusuallyusedfordecorativeapplicationsandwillexpandandcontractlessthanboardscutfromthelogbyothermethods.

Plain sawn

Toplainsawapieceofwoodmeanstocutittangentiallytoatree’sgrowthring.Thiscreatesaflame-shapedorcathedralpattern.Cuttingalogthiswayproducesmoreboardsandthusplainsawnboardsaremorecosteffective.Italsoexpandsandcontractsmorethanaboardcutbyothermethods.

Heartwood and sapwood

Heartwoodisthemorematurepartofthelog,closertothecenterofthetreeanddarkerincolor.Sapwoodisthelighter,youngerpartofthelogclosertothebark.

burl

Aburlisagrainpattern.Itisatwistoraswirlthatdoesnotcontainaknot.

mineral streaks

Thesearestreaksofcolorthatusuallyfollowthegrainpattern.

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Common deFeCTs oF HardwoodThefollowingarecharacteristicsofhardwoodthatareconsidereddefectswhengradingthequalityofapieceoflumber.

worm Holes

Theseareholesinthewoodthatrangeinsizefrom1/16”tomorethan1/4”.

split Thisisalengthwiseseparationofthewood.Itusuallyoccursasthepiecedries.Ifthereisaseparationalongthegrowthrings,itiscalledaShake.ACheckisalengthwiseopeninginthefaceoftheboard.Itdoesnotgothroughtheentireboardlikeasplit,butitisalsocausedbyfaultydrying.

Knot

Thisisacircularareawheretherewasoncethebaseofabranch.Insomecases,thewoodismissing.Othertimes,itmaybesolidwithnosignsofdecay..

GradinG aGenCies For HardwoodTheNationalHardwoodLumberAssociationestablishesthesegradesofhardwoodlumber.Sincehardwoodsarerarelyusedforstructuralpurposes,themainfactorinhardwoodgradingisappearanceandthenumberofclearcuttingspossiblefromapiece.

•Fas(FirstandSeconds).Themostpiecesclearofdefectsandalsothemostexpensive.Boardsaregenerally6”andwiderand8’andlonger.Usedforfinefurnitureandcabinetry.

•selects.Acost-effectivesubstituteforFASwhenonlyonegoodfacingisrequired.Boardsare4”andwider,6’andlonger.

•#1 Common.Ashoporthriftgradewhereboardsare2/3clearfacecuttings.Agoodvalueforwheresmallerpieces,4”x2’or3”x3’,canbeused.

• #2 Common.Boardshave50percentclearfaces.Generally3”andwiderand4’andlonger.Usedforsomepanelingandflooring.

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Appendix: LUMBeR

Chapter 2: selling Lumber module 1: board Feet

orderinG Lumber

Truckloads

• Youcanalsoorderlumberbythetruckload.Commontruckloadquantitiesvarybyspecieandbywhatgeographicalareatheycomefrom.

• Theyareusuallyabout27,000boardfeet(BF),rangingfrom23,000BFto30,000BF.

• Mostlumberwillbedeliveredbytruckdirectlytoyourhomecenterorlumberyard.However,youmayhaveitdeliveredbyrailcar.

railcar Loads

• Ifyouorderlumberisbytherailcar,youmightorderbytheboxcar,whichisusually80,000BF,butmightbefrom40,000to90,000BF.

• Aflatcarisusually112,000BF,butmightbefrom70,000to120,000BF.

• Muchofthelumbercostcanbethefreightchargesfromthemilltoyourstore.Therefore,freightchargescanbeadeterminingfactorinthekindoflumberyoustock.Certainminimumweightamountsgiveyouthebestfreightrate.

• Ifyouunloadlumberdirectlyfromatrain,youhaveacertainamountoftime,suchas48hours,tounloadacarafteritisinapositiontobeunloaded.Youarechargeddemurrageifyoutaketoolongtounload.

• Itiseasiertounloadiflumberisbandedtogether.

Lumber Producing regions

• Lumbercanbecategorizedbytheregionofthecountrywhereitisgrown.

• CoastlumberisconsideredtobeWestCoastspeciesgrownbetweenthePacificOceanandthemountainranges.ExamplesareDouglasFir-coastal,Larch,RedwoodandCedar.

• InlandlumberisconsideredtobefromtheWest,butharvestedeastofthecoastalplainsallthewaytotheGreatPlains.ExamplesareDouglasFir-inland,Larch,Cedar,IdahoWhitePineandHem-Fir.

• SouthernPineisthemajorspeciefromtheSouth-SoutheastpartoftheU.S.

• EasternwoodsfromtheAppalachianareaincludeSpruce,Fir,NorwayPine,VirginiaPonderosaPine,EasternWhitePineandmore.

• CanadianlumberismuchthesameastheWesternandEasternspecies,butisusuallynotedinthecodebookswith“North”followingthespecies.ExamplesincludeSpruce-Pine-Fir,DouglasFir,Hem-FirandalsoEastCoastspeciessuchasEasternWhitePine.

Lumber quantity chart

• Inthischartyoucanseesomestandardlumberunitquantitiesandsizes.

• Inthepieces/unitcolumn,thefirstnumberlistedforeachsizecategoryisthemostcommonlysoldunit.Thenextquantitiesarethoseusedbysomelumbermillsand/orwholesalers.Thesemaynotbeavailableinyourarea.

• •

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size Pieces/unit

2x4 294

2x4 192

2x4 180

2x4Studs 294

2x4Studs 312

2x4Studs 192

2x6Studs 189

2x6Studs 128

2x6 189

2x6 128

2x8 147

2x8 96

2x10 105

2x10 80

2x12 84

2x12 64

board Feet Practice Problems

Howmanyboardfeetareinthefollowingquantities?

1.7piecesof1x4–4’____________

2.560LFTof2x4_______________

3.25piecesof2x4–15’______________

Howmanylinealfeetareinthefollowingquantities?

4.1,500BFof1x8___________

5.210BFof2x4____________

6.800BFof2x10____________

Howmanypiecesoflumberareinthefollowingquantities?

7.1,100BFof2x4–16’____________

8.200BFof1x2–14’____________

Whatisthecostofthefollowingquantitiesoflumber,pricedat$550/M?

9.20pieces2x4–8’$________

10.9pieces1x4–16’$_________

11.300pieces2x4–16’$_________

12.1,000BF2x8$_____________

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module 4: board Feet

who publishes building codes?

•Therearethreemajorbuildingcodesthathaveevolvedasmodelbuildingcodes:theNationalBuildingCode(publishedbytheBuildingOfficialsandCodeAdministratorsInternationalInc.),theUniformBuildingCode(publishedbytheInternationalConferenceofBuildingOfficials)andtheStandardBuildingCode(publishedbytheSouthernBuildingCodeCongressInternationalInc.).

•TheInternationalCodeCouncilisacooperationofthreemajorbuildingcodes.ThiscouncilpublishestheInternationalResidential.•Inanefforttostandardizebuildingcodes,thesethreebuildingcodescooperateastheInternationalCodeCouncilandpublishtheInternationalResidentialCode(IRC)forOne-andTwo-FamilyDwellings. Common sTress TyPes

Followingisamoredetailedexplanationofthevariousstresstypesplacedonlumber.

Calculating modulus of elasticity

•Inthecourse,welearnedthatthemodulusofelasticityisabbreviatedEandishowmuchapieceoflumberwillsagordeflectinrelationtotheloadplacedonit.•Thebuildingcodewillsetalimitonhowmuchapieceoflumberisallowedtodeflect.Thesearereflectedinthespantables.

•Ageneralruleis1/360thofthespan.Thatisamaximumsagof1”forevery360”(30’)ofjoistlength.

•Youcanfigurethedeflectionbychangingthespanlengthintoinchesthendividingby360.

Answers:

1.9-1/3

2.373-1/3

3.250

4.2,250

5.315

6.480

7.103+

8.85+

9.107BF/$58.85

10.48BF/$26.40

11.3,200BF/$1,760.00

12.1,331BF/$733.70

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•Thespantablesweusedpreviouslywereacceptableforspanlimits.Asadoublecheck,notethesymbolL/=360intheupperright.Thatindicatesthedeflectionlimitis1/360,acceptableforcode.•Typically,thesedeflectionlimitsdonotmeanthatthejoistswillactuallysagtothefullacceptableamountanytimeyouusethem.Morethanlikely,thepieceoflumberyouareusingwillsaglessbecauseitisnotbeingloadedorspannedtocapacity.•Codesallowceilingjoistsslightlymoredeflection,commonly1/240thofthespan.•ModulusofElasticityisaratiobetweentheamountamaterialwilldeflectinproportiontoaload.Itisrepresentedby“E”andexpressedinpsi(poundspersquareinch).Thatvalueisoftenshortenedbydividingby1million.Example:AnEvalueof1,500,000isoftencalled1.5E.

Compression Parallel to Grain •AbbreviatedFC.•Anormalstressonapost,column,stud,etc.

•Typicalstresswheretheloadissupportedontheendofthepiece.•Thefibersinthewoodareuniformlystressed.Stressisparalleltoandalongthefulllengthofthewood.•Rarelyaprobleminhomeconstructionasmostlumberisverystrong.•TheoppositekindofstressisFiberStressinTension(Ft),thenthestressesonthelumberistryingtopullitapart.Thisisrareinhousebuildingandrarelyafactorinchoosinglumber.

Compression Perpendicular to Grain

•AbbreviatedFC•Thestresswhenafloorjoist,ceilingjoist,beam,etc.,restsonasupport.Theloadtendstocrush,orcompress,thefibersatthebearingpoint.•Thebearingareahastobelargeenoughsothattheloaddoesn’tcrushthefibersatthesidegrain.•Buildingcodessetminimumbearingsforlumber.•Minimumbearingforwoodfloorandceilingjoists,rafters,beamsandgirdersis1-1/2”onwoodand3”onmasonry.Joiststhatarelappedmustbelappedatleast3”.Ifyoufollowtheseminimums,youwon’thavetoworryaboutcompressionperpendiculartothegrain.

Horizontal shear

•Stresswhenwoodfibersslideoverthemselveshorizontallyrightatthetoptobottommid-pointofthemember.•Theonlytimewhenthisstressisaproblemisinshort,heavilyloadedbeamsthataredeep.•Thesolutionistoincreasebeamcrosssection.