ansi rd1.0_2006 - standard for steel roof deck

s

AmericAn nAtionAl stAndArds institute/ steel deck institute

Steel Roof Deck

STEEL DECKINSTITUTE

s ®

copyright 2007 steel deck institute

RD1.0 - 2006 Standard for

�

Steel Roof DeckRD1.0 - 2006 Standard for

AmericAn nAtionAl stAndArds institute/ steel deck instituteSTEEL DECKINSTITUTE

s ®

1. General

1.1 Scope:

A. ThisSpecificationforSteelRoof Deckshallgovernthematerials, design,anderectionofcold formedsteeldeckusedforthe supportofroofingmaterials, designliveloadsandSDI constructionloads.

B. Commentaryshallnotbe consideredpartofthe mandatorydocument.

1.2 ReferenceCodes, StandardsandDocuments:

A. CodesandStandards:For purposesofthisStandard,comply withapplicableprovisionsofthe followingCodesandStandards:

1. AmericanIronandSteel Institute(AISI)Standard- North American Specification for the Design of Cold-Formed Steel Structural Members, 2001EditionwithSupplement 2004

2.AmericanWeldingSociety- ANSI/AWSD1.3Structural WeldingCode/SheetSteel- 98StructuralWeldingCode- SheetSteel

3. AmericanSocietyforTesting andMaterials(ASTM)A653 (A653M)-06,A924(A924M)-06, A1008(A1008M)-06

4. AmericanSocietyofCivil Engineering(ASCE)– SEI/ASCE7-05

5. UnderwritersLaboratories(UL) FireResistanceDirectory- http://www.ul.com/database 2006

B. ReferenceDocuments:Referto thefollowingdocuments:

1. SDIManualofConstruction withSteelDeck-MOC2-2006

2. SDIStandardPracticeDetails- SPD2-2001

3. SDIPositionStatement-Field PaintingofSteelDeck-2004

4. SDIDiaphragmDesignManual- DDM03-2004

2. Products2.1 Material:

A. Sheetsteelforgalvanizeddeck shallconformtoASTMA653 (A653M)StructuralQuality,with aminimumyieldstrengthof 33ksi(230MPa).

B. Sheetsteelforcoldrolledplus painteddeckshallconformto ASTMA1008(A1008M)witha minimumyieldstrengthof 33ksi(230MPa).Otherstructural sheetsteelsorhighstrengthlow alloysteelsareacceptable, andshallbeselectedfromthe North American Specification for the Design of Cold-Formed Steel Structural Members.

C. Sheetsteelforaccessoriesshall conformtoASTMA653(A653M) StructuralQualityforstructural accessories,ASTMA653(A653M) CommercialQualityfor non-structuralaccessories,or ASTMA1008(A1008M)foreither structuralornon-structural accessories.Otherstructural sheetsteelsorhighstrengthlow alloysteelsareacceptable,and shallbeselectedfromtheNorth American Specification for the Design of Cold-Formed Steel Structural Members.

D.Thedecktype(profile)and thickness(gage)shallbeas shownontheplans.

2.2 Tolerance:

A. Uncoatedthicknessshallnotbe lessthan95%ofthedesign thicknessaslistedinTable2.2.1:

B. Panellengthshallbewithinplus orminus1/2inch(12mm)of specifiedlength.

C. Panelcoverwidthshallbeno greaterthanminus3/8inch (10mm),plus3/4inch(20mm).

D.Panelcamberand/orsweepshall benogreaterthan1/4inchin 10footlength(6mmin3m).

E. Panelendoutofsquareshallnot begreaterthan1/8inchperfoot ofpanelwidth(10mmperm).

2.3 Finish:

A.Galvanizingshallconformto ASTMA653(A653M).

B. Paintedwithashopcoatof primershallbeappliedtosteel sheetconformingtoASTMA1008 (A1008M).

C. Thefinishofthesteelroofdeck shallbesuitableforthe environmentofthestructure.

Table2.2.1 Gage Design Minimum No. Thickness Thickness in. mm. in. mm. 22 0.0295 0.75 0.028 0.71 21 0.0329 0.84 0.031 0.79 20 0.0358 0.91 0.034 0.86 19 0.0418 1.06 0.040 1.01 18 0.0474 1.20 0.045 1.14 17 0.0538 1.37 0.051 1.30 16 0.0598 1.52 0.057 1.44

�



s ®

2.3 Finish:

Commentary:Theprimer coatisintendedtoprotectthe steelforonlyashortperiodof exposureinordinaryatmospheric conditionsandshallbe consideredanimpermanentand provisionalcoating.Field paintingofprimepainteddeckis recommendedespecially wherethedeckisexposed.(See SDIField Painting of Steel Deck).

Incorrosiveorhighmoisture atmospheres,agalvanizedfinish isdesirableinaG60(Z180)orG90 (Z275)coating.Inhighly corrosiveorchemical atmospheresorwherereactive materialscouldbeincontact withthesteeldeck,specialcare inspecifyingthefinishshould beused.

2.4 Design:

A.Thedeckshallbeselectedby thedesignertoprovidetheload capabilitiesshownonthe drawings(designliveanddead loadsandtheSDIconstruction loads).

1. Thesectionpropertiesof thesteelroofunitdeckshall becomputedinaccordance withtheNorth American Specification for the Design of Cold-Formed Steel Structural Members.

2.AllowableStressDesign(ASD): Bendingstressshallnot exceed0.60timestheyield strengthwithamaximumof 36ksi(250MPa)underthe combineddeadanddesign liveloads.

3.LoadandResistanceFactor Design(LRFD):Theload

factorsaredefinedinthe governingcode.ASCE7(See section1.2.A.5)shallbeused intheabsenceofagoverning code.Theresistancefactors andnominalresistances shallbedeterminedin accordancewiththeNorth American Specification for the Design of Cold-Formed Steel Structural Members.

4.DeckDeflection:Deflectionof thedeckshallnotexceed 1/240ofthespan(centerline tocenterline)or1inch (25mm),whicheverisless, undertheuniformly distributeddesignliveload.All spansaretobeconsidered center-to-centerofsupports.

Commentary:Theadequacyof deckedgesupportdetailsshould bereviewedbythedesigner.At thebuildingperimeterorany otherdeckterminationor directionchange,occasional concentratedloadingofthe roofdeckcouldresultin temporarydifferencesin deflectionbetweentheroofdeck andtheadjacentstationary buildingcomponent. Supplementalsupportsuchasa perimeteranglemaybe warranted.

5.SuspendedLoads:All suspendedloadsshallbe includedintheanalysisand calculationsforstressand deflection.

Commentary:Thedesignermust takeintoaccountthesequence ofloading.Suspendedloadsmay includeceilings,lightfixtures, ductsorotherutilities.The designermustbeinformedofany loadsappliedaftertheroofing hasbeeninstalled.

6. ConstructionandMaintenance Loads:Deckshallbeselected bythedesignertoprovide aminimum30lbs/sq.ft. (1.44kPa)constructionload. Spanlengthsshallbe governedbyamaximum stressof0.7Fyanda maximumdeflectionof1/240 ofthespanwitha200-pound (0.89kN)concentratedloadat midspanona1foot(300mm) widesectionofdeck.Ifthe designercontemplatesloads ofgreatermagnitude,spans shallbedecreasedorthe thicknessofthesteeldeck increasedasrequired.Allloads shallbedistributedby appropriatemeanstoprevent damagetothecompleted assemblyduringconstruction.

7.Cantileverloads:The cantileverspanshallbe determinedbythelowest valueconsidering, (a)constructionphaseloadof 10psf(0.48kPa)onadjacent spanandcantilever,plus 200poundload(0.89kN)at endofcantileverwithastress limitof0.7Fy(ASD), (b)aserviceloadof45psf (2.15kPa)onadjacentspan andcantilever,plus100pound load(0.44kN)atendof cantileverwithastresslimitof 0.6Fy(ASD),or (c)withserviceloads,a deflectionlimitationof1/240 ofadjacentspanforinterior spananddeflectionlimitation atendofcantileverof1/120 ofoverhang.

Commentary:Under ConstructionandMaintenance Loads,andCantileverLoads,0.7Fy maximumstresswasselectedto unifytheASDandLRFDvalues. Applyaloadfactorof1.4to200 poundloadwhenLRFDisused.

�



s ®

8.DiaphragmShearCapacity: Roofdeckshearcapacity shallbedeterminedin accordancewiththeSDI Diaphragm Design Manualor fromtestsconductedbyan independentprofessional engineer.

Commentary:Calculationsof diaphragmstrengthandstiffness shouldbemadeusingtheSDI Diaphragm Design Manual. If testingisusedasthemeansfor determiningthediaphragm strengthandstiffness,thenit shouldfollowtheAISITS7-02test protocol.

B. LoadTables:Uniformloads determinedforpublishedtables shallbebasedonequaladjacent twoandthreespanconditions andonsinglespans.Appropriate combinationsofshearand bendingshallbemadeto determinethepublishedloads. Lengthsof1-1/2inches(38mm) forendbearingand4inches (100mm)forinteriorbearing shallbeusedtocheckweb crippling.Deflectioncoefficients shallbe0.013forsinglespans, 0.0054fordoublespansand 0.0069fortriplespans.

Commentary:Fordecklayouts thatprovidemorethanthree equalspans,theusercanapply theloadspublishedforthree spans.Publisheduniformload tablesdonotapplyforadjacent spansthatdifferinlengthby morethan10%.

2.5 Accessories:

A. Ridgeandvalleyplates,andflat platesatchangeofdeckdirection shallbefurnishedasshownon planstoprovideaflat(finished)

surfacefortheapplicationofroof insulationandroofcover.

B. Sumppansshallbefurnishedto receiveroofdrainsasshownon plans.Holesfordrainsaretobe fieldcut(byothers)inthefield.

C. Mechanicalfastenersorwelds shallbepermittedfordeckand accessoryattachment.

3. Execution3.1 Installation/General:

A. Supportframingandfield conditionsshallbeexaminedfor compliancewithrequirements forinstallationtolerancesand otherconditionsaffecting performanceofworkofthis section.AllOSHArulesfor erectionshallbefollowed.

B. Deckpanelsandaccessories shallbeinstalledaccordingto theSDIManual of Construction with Steel Deck,placementplans, andrequirementsofthisSection.

C. Deckpanelsshallbeplacedon structuralsupportsandadjusted tofinalpositionwithendsaligned, andattachedsecurelytothe supportsimmediatelyafter placementinordertoforma safeworkingplatform.Alldeck sheetsshallhaveadequate bearingandfasteningtoall supportstopreventslipoff duringconstruction.Deckends oversupportsshallbeinstalled withaminimumendbearing of1-1/2inches(38mm).Deck areassubjecttoheavyor repeatedtraffic,concentrated loads,impactloads,wheelloads, etc.shallbeadequatelyprotected byplankingorotherapproved meanstoavoidoverloadingand/or damage.

D.LappedorButtedEnds:Deck endsshallbeeitherlappedor buttedoversupports.Gapsup to1inch(25mm)shallbe permittedatbuttedends.

E. Deckunitsandaccessoriesshall becutandneatlyfitaround scheduledopeningsandother workprojectingthroughor adjacenttothedecking.

Commentary:Itisthe responsibilityofthedesignerto designateholes/openingstobe deckedoverincompliancewith applicablefederalandstate OSHAdirectives.Careshouldbe takentoanalyzespansbetween supportsatopenings,when determiningthoseholes/ openingstobedeckedover. Whenaframedopeningspan exceedsthemaximumdeckspan limitsforconstructionloads,the openingmustbedetailedaround insteadofdeckedover. (Minimumroofconstruction load30lbs/sqft(1.44kPa),unless jobspecificrequirementsdictate otherwise).

F. Tradesthatsubsequentlycut unscheduledopeningsthrough thedeckshallberesponsible forreinforcingtheseopenings baseduponanapproved engineereddesign.

�



s ®

3.2 Installation/Anchorage:

A. Roofdeckunitsshallbeanchored tosteelsupportingmembers includingperimetersupport steeland/orbearingwallsbyarc spotweldsofthefollowing diameterandspacing,fillet weldsofequalstrength,or mechanicalfasteners.Anchorage shallprovidelateralstabilityto thetopflangeofthesupporting structuralmembersandresist thefollowingminimumgross uplifts;45poundspersquare foot(2.15kPa)foreaveoverhang; 30poundspersquarefoot (1.44kPa)forallotherroofareas. Thedeadloadoftheroofdeck constructionshallbededucted fromtheaboveforces.

1. Allweldingofdeckshallbe inaccordancewithANSI/AWS D1.3,Structural Welding Code - Sheet Steel.Eachweldershall demonstrateanabilityto producesatisfactorywelds usingaproceduresuchas shownintheSDIManual of Construction with Steel Deck, and/orasdescribedin ANSI/AWSD1.3.

2. Weldingwashersshallbe usedonalldeckunitswith metalthicknesslessthan 0.028inches(0.7mm).Welding washersshallbeaminimum thicknessof0.0598inches (16gage,1.50mm)andhavea nominal3/8inch(10mm) diameterhole.

3.Whereweldingwashersare notused,aminimumvisible 5/8inch(15mm)diameter arcpuddleweldshallbeused. Weldmetalshallpenetrateall layersofdeckmaterialatend lapsandshallhavegood fusiontothesupporting members.

4.Weldspacing:Ribsofpanels shallbeweldedateach support.Spaceadditional weldsanaverageof12inches (300mm)apartbutnotmore than18inches(460mm). 5.Whenused,filletweldsshall beatleast1-1/2inches (38mm)long.

6. Mechanicalfasteners,either powderactuated, pneumaticallydriven,or screws,shallbepermittedin lieuofweldingtofasten decktosupportingframing iffastenersmeetallproject servicerequirements.When thefastenersarepowder actuatedorpneumatically driven,theloadvalueper fastenerusedtodetermine themaximumfastenerspacing isbasedonaminimum structuralsupportthicknessof notlessthan1/8inch(3mm) andonthefastenerproviding aminimum5/16inch(8mm) diameterbearingsurface (fastenerheadsize).Whenthe structuralsupportthickness islessthan1/8inch(3mm), powderactuated or pneumaticallydrivenfasteners shallnotbeused,butscrews areacceptable.

Commentary:Mechanical fasteners(screws,powderor pneumaticallydrivenfasteners, etc.)arerecognizedasviable anchoringmethods,provided thetypeandspacingofthe fastenersatisfiesthedesign criteria.Documentationinthe formoftestdata,design calculations,ordesigncharts shouldbesubmittedbythe fastenermanufacturerasthe basisforobtainingapproval.

7. Fordeckunitswithspans greaterthan5feet(1.5m), sidelapsandperimeteredges ofunitsbetweenspan supportsshallbefastenedat intervalsnotexceeding 36inches(1m)oncenter, usingoneofthefollowing methods: a.#10selfdrillingscrews. b.Crimporbuttonpunch. c.Arcpuddlewelds5/8inch (15mm)minimumvisible diameter,orminimum 1inch(25mm)longfillet weld.

Commentary:Theabovesidelap spacingisaminimum.Service loadsordiaphragmdesignmay requirecloserspacing.Good metaltometalcontactis necessaryforagoodsidelap weld.Burnholesaretobe expected.

B. AccessoryAttachment:

1. Accessoriesshallbeanchored tosupportingmembersby arcspotweldsorselfdrilling screwsat12inches(300mm) maximumintervalsoras shownondesigndrawings.