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7/30/2019 Speci Fiers Builders Guide June 2010
1/24
June 2010(Replaces November 2005)
S P E C I F I E R S A N D B U I L D E R S G U I D E
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Description
Quality Accreditation 1
Design for Durability 1
AnimalShelters 1
Corrosion 2
Run-offfromInertMaterials 3
DrinkingWater 4
EdgeSealingofCOLORSTEELProducts 4
ExpansionAllowanceandTemperature 4
FixingsandFasteners 5
FluesDomestic/Industrial 6
FootTrafficonRoofs 6
FumeExtractorsandVents 7
GeothermalAreas 7
MixingofBrands 8
Overpaintingof
COLORSTEELPrepaintedSteelProducts 8
ProcessingPlants 8
ProfileBendDiameters
Roofing,Wal lCladdingandAccessories 9
SolarHeatingPanelsorRubberMats 9
SwarfStainingofRoof ingandCladding 10
UnwashedAreas 10
WaterPonding 12
WeatheringofCOLORSTEELProducts 12
New Zealand Steel Limited Products
and the New Zealand Building Code 13
ConformingwiththeBuildingCode 13
ExternalMoistureE2/AS1 13
Fire:OutbreakofFire
BuildingCodeC/AS1 13
ControlofExternalFireSpread 14
Maintenance 14
Environmental Categories and
Product Recommendations 15-18
SpecialEnvironments 19
CommercialWarranties 20
Installation Information 21
InformationtoHelpAvoidProblems 21
Technical Features 22
CorrosionProtection 22
UVProtection 22
Profile Design Information 23
How to Specify
New Zealand Steel Limited
Roofing and Cladding Products 23
FurtherCoating/SurfaceOptions 23
FurtherInformation
CONTENTS
DESCRIPTIONDESCRIPTION
NewZealandSteelproducesarangeofcoatedsteelproducts.
COLORSTEELprepaintedsteeldescribesthosesteelbuilding
materialswhichhaveoven-curedpaintappliedtoagalvanised
orZINCALUMEsteelbaseonacontinuouscoiltocoil
operationattheNewZealandSteelGlenbrookworks.
Theprepaintingprocessgivesexcellentadhesionofthecoating
tothesubstrate,allowingrollformingtobeperformedafter
paintingwithoutdelaminationordeteriorationofthepaintfilm.
AvarietyofCOLORSTEELprepaintedsteelcoatingtypesis
offered.AllCOLORSTEELproductsareproducedusingeither
aZINCALUMEsteelsubstratewithanAZ150orAZ200
coatingclass,(i.e.:150g/m2or200g/m2ofzinc/aluminiumalloy),
oragalvanisedsteelsubstratewithaZM275coatingclass
(i.e.275g/m
2
ofzinc).DatasheetsoneachoftheCOLORSTEELprepaintedsteel
coatingtypesmaybeobtainedfromNewZealandSteelLimited
oranystockistsofCOLORSTEELprepaintedsteel.
COLORSTEELMAXXproductshaveaZINCALUMEcoated
steelbase.ThisproductisintendedforVerySevereenvironments.
COLORSTEELENDURAprepaintedsteelhasa
ZINCALUMEcoatedsteelbaseandisavailableinarangeof
colours,selectedfortheirabilitytoprovideoptimum
performance,durabilityandappeal.
ZINCALUMEzinc/aluminiumalloycoatedsteelhasa45%
zinc,55%aluminiumalloycoatingwhichofferssuperior
corrosionresistancecomparedtogalvanisedsteelinmost
environments(particularlycoastalenvironments).
Traditionalgalvanisedsteelisofferedunderthetradenameof
GALVSTEEL.Thismaterialhasa100%zinccoatingandis
availableinarangeofdimensions,grades,zinccoatingweightsandtypes.
AXXISSteelforFramingisabrandofgalvanised,high-tensile
steelsuppliedforsteelframesandtrusses,usedinresidential
andsimilarconstruction.
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DatasheetsoneachoftheCOLORSTEELprepaintedsteelcoatingtypesmaybeobtainedfromNewZealandSteelLimitedoranystockistsofCOLORSTEELprepaintedsteel.
Wherethereisarequirementforaverydurableproductwithhighaestheticappealandlowcostsof
installationandmaintenance,thenCOLORSTEELprepaintedsteelproductsshouldbespecified.
Eachproductisdesignedforapplicationinaspecificenvironment.Theseapplicationsarediscussed
undertheheadingTheNewZealandBuildingCodelaterinthispublication.
QUALITY ACCREDITATIONQUALITY ACCREDITATION
TheNewZealandSteelLimitedPaintLinereceivedaccreditationtoISO9002inApril1992andhassubsequentlybeenupgradedtoISO9001sinceJuly1993.Anon-goingprogrammeofcontinuous
improvementwillensurethatpracticeatNewZealandSteelLimitedcontinuestoreflectthebestavailableinternationaltechnology.
DESIGN FOR DURABILITYDESIGN FOR DURABILITY
Designhasamajorimpactonthedurabilityofthebuilding.Agooddesignwillensurethatyouwillgetthebestpossiblelifefromyourbuildingandreducemaintenancecosts.
The following design elements are presented alphabetically with guides to provide
improved durability.
ANIMAL SHELTERSANIMAL SHELTERS
Someagriculturalapplicationsmaycreateinternalenvironmentsinwhichthebuild-upofpollutants
orfumesisapotentialsourceofcorrosion.Acorrosiveammoniaenvironmentcandevelopwithinshedsusedforintensiveanimalfarming.
ZINCALUME,COLORSTEELENDURAorCOLORSTEELMAXXshouldnotbeusedforthisapplication.
Design Guide:Design Guide:
1. ContactNewZealandSteelLimitedforspecialistadvice.
2. ZINCALUMESTEELORCOLORSTEELSHOULDNOTBEUSEDINTHISENVIRONMENT
DUETOEXTREMECORROSIONRISK.
PAGE
ONE
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CORROSIONCORROSION
Dissimilar Metals CorrosionDissimilar Metals Corrosion
Whentwodifferentmetalsareincontactandmoistureispresent,onemetalisrelativelyprotected
whiletheothersuffersacceleratedcorrosion.Thisisknownasgalvanicorbi-metalliccorrosion.
Asimilareffectcommonlyoccurswithwaterflowingoverdissimilarmetals.
Thisformofcorrosioniscommonlyfound:
1. Wherewaterisdischargedfromcopperorbrasssystemsoveragalvanised,orCOLORSTEEL
prepaintedsteelorZINCALUMEcoatedsteelroof.
2. WhereunpaintedleadflashingsareapplieddirectlytoZINCALUMEcoatedsteelproducts.
(ReferInformationBulletinNo.2FlashingMaterials).
3. Wherefastenersareincompatiblewiththeroofingmaterial.(SeeFixingsandFasteners,page5).
Design Guide:Design Guide:
1. SeparatedissimilarmetalsbyusingabarriersuchasPVCtape,neutralcuresiliconesealant
oranappropriatepaintsystem.
2. Preventpotentialrun-offfromcopperorbrasspipesoverGALVSTEEL,ZINCALUMEcoated
steelorCOLORSTEELprepaintedsteelsurfacesbydivertingthedischargeclearoftheroofing.
CopperpipesmustbeisolatedfromAXXISSteelforFraming.
Note: Coastal areas
with high salt levels
and high humidity
will increase the
possibility of
dissimilar metals
corrosion.
Compatibility
More Active Metals
More Noble Metals
Thischartlistscommonlyusedmetals
inaGalvanicSeries.Ifanyofthese
metalsareindampcontactora
runoffsituation,themetalhigheron
thetablewillsacrificeitselftoprotect
themetalloweronthescale.
Thereforethesimpleruleisto
rememberthatyoucanrunwater
downbutnotuphill.Forexample,zinctocopperisalrightbutcoppertozinc
isnot.
ZINC
ZINCALUME
ALUMINIUM
STEEL
LEAD
COPPER
STAINLESS STEEL
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RUN-OFF FROM INERT MATERIALSRUN-OFF FROM INERT MATERIALS
Thezinccoatingongalvanisedsteelproductsdevelopsaprotectivesurfacefilmasaresultofnaturalweathering.ThisprovidesthelongevityofperformancewhichwehavecometoexpectfromGALVSTEELproducts.
Whenflowingovergalvanisedroofing,rainwaterdissolvessmallamountsofmineralsandsaltsfrom
thezincsurface.Thesemineralsandsaltspromoteandmaintaintheprotectivefilmandenhancethecorrosionresistanceofdownstreamgalvanisedsteelproducts(eg:lean-toroofs,guttersandvalleys).
Howeverwhenrainwaterflowsover,oriscollectedfromroofingmaterialswhichdonotpromotethisprotectivefilm(INERTMATERIALS),acceleratedcorrosionofunpaintedgalvanisedsteelroofsand
gutterscanoccur.
SomeExamplesofInertMaterials:
ZINCALUMEsteelGlassFibreglassCOLORSTEELprepaintedsteelGlazedTilesPVC
AcrylicAluminium
Design Guide:Design Guide:
1. Ongalvanisedroofing,runskylightsdowntothegutter.
2. ToachievemaximumlifefromyourrainwatergoodswerecommendthattheyaremanufacturedfromeitherZINCALUMEsteelorCOLORSTEELprepaintedsteelproducts.
3. Unpaintedgalvanisedsteelmustnotbeusedforroofingorrainwatergoods,includingvalleysandgutters,tocollectwaterrun-offfromZINCALUMEcoatedsteelproductsoranyotherinertmaterial.
PAGE
THREE
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DRINkING WATERDRINkING WATER
RainwatercollectedfromroofscladwithproductsmadefromGALVSTEEL,ZINCALUMEcoatedsteelandCOLORSTEELprepaintedsteel,willcomplywiththeprovisionsofNZBCG12.3.1,
providedthewaterisnotcontaminatedfromothersources.
Thefirst25mmofrainfallfromanewlyinstalledroofmustbediscardedbeforedrinkingwater
collectionstarts.
Whereapaintorpaintsystemisappliedtotheroof,itssuitabilityforthecollectionofdrinkingwater
mustbeestablished.
EDGE SEALING OF COLORSTEELEDGE SEALING OF COLORSTEEL PRODUCTSPRODUCTS
EdgesealingofCOLORSTEELproductsisnotrecommended.(SeeEnvironmentalCategoriesand
ProductRecommendationssection).
EXPANSION ALLOWANCE AND TEMPERATUREEXPANSION ALLOWANCE AND TEMPERATURE
Allroofingandcladdingissubjecttoexpansionandcontractionduetotemperatureextremes.This
isparticularlyevidentwithdarkercoloursandlongspanswheretheexpansionmaybeasmuchas8.0mmfora10.0metresheet.Fixingsystemsmustallowforexpansionandaccommodatethelongitudinalmovementwhichresults.
Design Guide:Design Guide:
Typical Roof Temperatures Summer Average - Calm Conditions
INSULATED UNINSULATED
LightColours(egTitania)* 58C 48C
MediumColours(egMistGreen) 79C 67C
DarkColours(egKaraka) 92C 77C
*Light Colours include
unpainted galvanised
and ZINCALUME
steel material.
Typical Roof Expansions
Basedon0.01mm/m/C
8 METRE RUN 12METRERUN 18 METRE RUN
LightColours* 5mm 7mm 11mm
MediumColours 6mm 10mm 14mm
DarkColours 7mm 11mm 17mm
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PAGE
FIVE
FIXINGS AND FASTENERSFIXINGS AND FASTENERS
Theselectionoftheappropriateformoffastenerisataskwhichshouldnotbesolelyinfluencedbycost.Fastenercostsareminimalrelativetotheoverallprojectandthereisnobenefittobegained
throughtheuseofinferiorfixings.Thefastenerdurabilityshouldequalorexceedthatoftheroofingorcladdingproduct.
TheMetalRoofingandWallCladdingCodeofPracticeprovidessomeinformationonselection,fixingmethodsandplacementoffasteners.ThishandbookisavailableonrequestfrommembersoftheNewZealandMetalRoofingManufacturersIncorporatedorNewZealandSteelLimited.More
detailedinformationcanalsobeobtainedfromfastenermanufacturers.
Design Guide:Design Guide:
1. FastenerperformanceshouldconformwiththerequirementsofAS3566(andAmendments)
ScrewsSelfDrillingfortheBuildingandConstructionIndustries.
2. Stainlesssteelandstainlesssteelcappedfastenersarenotrecommendedforusewith
ZINCALUMEcoatedsteelorCOLORSTEELprepaintedsteelproductsinallenvironmentsduetoincompatibility.
3. Lowcarbon,nonconductingsealingwashersarerequiredforusewithCOLORSTEELprepaintedsteelproductsandZINCALUMEcoatedsteelproducts.
Theadviceofspecialistfastenermanufacturersisreadilyavailableandthesemanufacturers shouldbeconsulted,particularlywhereCOLORSTEELprepaintedsteelproductsaretobe fixedinVerySevereorSevereEnvironments.(seeEnvironmentalCategoriesandProduct Recommendations,page15).
4. Fastenerswithheavyzincorzinc-tincoatingsorzincalloycoatedheadscomplyingwithAS3566Class3and4arefullycompatiblewithallproducts.
5. FastenersusedonCOLORSTEELprepaintedsteelproductsshouldbefactorycoatedto provideanaccuratecolourmatchwithCOLORSTEELprepaintedfinishes.
6. Rivets:Rivets:
UsealuminiumrivetsforjoiningallNewZealandSteelLimitedroofingproducts. (Ensurerivetisofasuitablestrengthforthepurpose.Refertoyourrivetsupplier).
Monelrivetsarenotrecommendedastheyareincompatibleduetotheircoppercontent.
NR:NewZealandSteelproductnotrecommendedforexteriorapplicationsfortheseEnvironmentalCategories.
4: Heavyzincorzinc-tincoatingsorzincalloycoatedheadscomplyingwithAS3566.22002Class4.
3: Heavyzincorzinc-tincoatingscomplyingwithAS3566.22002Class3.
*Seepage16fordefinitionsofEnvironmentalCategories.
Note:
1. StainlesssteelfastenersarenotrecommendedforusewithZINCALUMEcoatedsteelor
COLORSTEELprepaintedsteelproductsinallenvironments.2. Sealingwashersthatcontaincarbonblackfillerlevelsofmorethan15%byvolumemay
leadtocorrosionofZINCALUMEsteelandCOLORSTEELprepaintedsteelproducts.Therefore,allfastenersforNewZealandSteelroofingproductsshouldhavelowcarbon,
non-conductingsealingwashers.
3. RefertoInformationBulletin10.
Fastener Recommendations
Environmental ISO GALVSTEEL ZINCALUME COLORSTEEL COLORSTEELCategory* ENDURA MAXX
Coastal:VerySevere C5 NR NR NR 4
Severe C4 NR NR 4 4
Moderate C3 3,4 3,4 3,4 3,4
Industrial:
VerySevere C5 NR NR NR 4
Severe C4 NR NR 4 4
Moderate C3 3,4 3,4 3,4 3,4 Inland:
Moderate C2 3 3 3 3,4
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FLUES DOMESTIC/INDUSTRIALFLUES DOMESTIC/INDUSTRIAL
Naturalgas,wood,coaloroil-firedheatersgeneratehighlevelsofsulphurcompounds.Whenventedoveraroof,particularlyindampconditions,sulphuricacidformswhichwillleadto
prematurecorrosionoftheroof,gutteringanddownpipes.
Design Guide:Design Guide:1. Designtheheightofthefluetoallowcombustionby-productstobedissipated.
2. SpecifyaCOLORSTEELprepaintedsteelproductdesignedforverysevereenvironments.
3. Ensurethatheatersarerunasefficientlyaspossibletoallowcompletecombustion.
4. Regularlywashtherooftoremovecontaminants.
FOOT TRAFFIC ON ROOFSFOOT TRAFFIC ON ROOFS
Repeatedfoottrafficandthedraggingofmaintenanceorcleaningequipment,maydamagetheroofwhichwillreduceitslifeexpectancy.
Design Guide:Design Guide:
1. Designandinstallcatwalksandplatformsovertheroofwherenecessary.2. Aluminiumorgalvanisedsteelcatwalksarerecommended.
3. Designcatwalksandplatformssoasnottocreateanunwashedorpondingareaontheroof.
4. Timbercatwalksandplatformswillcausepreferentialcorrosionofunderlyingroof.
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PAGE
SEVEN
FUME EXTRACTORS AND VENTSFUME EXTRACTORS AND VENTS
Corrosivedustandparticlescanbereleasedthroughroofventsanddischargedontotheroofsurface.Theimmediateareaoftheroofadjacenttotheventisthenatincreasedriskofcorrosion.
Design Guide:Design Guide:
1. Installfilterelementstocontainhazardousmaterial.
2. SpecifyaCOLORSTEELprepaintedsteelproductdesignedforverysevereenvironmentsto beinstalledadjacenttothevent.
3. Considerapplyingasuitableprotectivecoatingtotheaffectedareaoftheroof.
4. Maintaincoaloroilfiredboilersorincineratorssothattheydonotdischargehighsulphur levelsovertheroofsurface.
5. Regularlywashtherooftoremovecontaminants.
GEOTHERMAL AREASGEOTHERMAL AREAS
Inareasofgeothermalactivity,hydrogensulphidesassociatedwithboreemissionscancausecorrosionproblems.Althoughheavierthanair,hydrogensulphidecanbedrawnintorainwaterdown-
pipesandaccumulateingutters.Thiscanleadtocorrosionoftheguttersandtheroofoverhangs.
Design Guide:Design Guide:
1. Installawatertrapatthebaseofdown-pipes.
2. SpecifytheappropriateCOLORSTEELprepaintedsteelproduct.
3. ContactNewZealandSteelLimitedforspecialistadvice.
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MIXING OF BRANDSMIXING OF BRANDS
Wheredifferentbrandsofprepaintedmaterialareusedonthesamebuilding,differencesincolour,glossandweatheringperformancemayappearobviouswithinashortperiodoftime.Thiswillbe
duetothedifferentpaintformulationsusedbydifferentmanufacturers.
NewZealandSteelLimitedwillnotacceptliabilityforproblemscausedbythemixingofbrands.
Design Guide:Design Guide:
1. SpecifyeitherCOLORSTEELENDURAorCOLORSTEELMAXXproducts.
OVERPAINTING OF COLORSTEELOVERPAINTING OF COLORSTEEL PREPAINTED STEEL PRODUCTSPREPAINTED STEEL PRODUCTS
COLORSTEELprepaintedsteelproductsaredesignedfordurability.However,allpaintcoatingswilldeteriorateovertime.Therefore,atsomestage,itwillbenecessarytorepainttoavoidseriousdeteriorationoftheproduct.
Themainconsiderationisthepaintcoatingintegritytoperformasuitablebondfortheoverpaintedsystemsothatthedurabilityofthenewcoatingsystemismaintained.
NewZealandSteelsexperiencewouldindicatethatthisperiodtofirstrepaintisaround15years.
However,localclimaticconditions,buildingdesignandpaintcolourcanhaveasignificantinfluenceontheperformanceofthepaintsystem.ThereforeyoumayneedtoconsultNewZealandSteelorourpaintsuppliers,PPGIndustriesNZLtd,tohelpassessthemostsuitabletimetorepaint.
COLORSTEELprepaintedsteelproductsmaybereadilyoverpainted,aftersuitablepreparation,foraestheticreasons.DetailedinformationisavailableintheNewZealandSteelLimitedInformation
Brochure:OverpaintingNewandWeatheredSteelRoofing.
PROCESSING PLANTSPROCESSING PLANTS(IncludingSwimmingPools)
Somecommercialapplicationsmaycreateinternalenvironmentsinwhichthebuild-upofpollutantsorfumesareapotentialsourceofcorrosion.Plantswherechlorinevapoursarereleased(includingenclosedswimmingpools)shouldhaveadequateventilationtominimisetherisks.
Design Guide:Design Guide:
1. Wherepollutantsorhumiditylevelsarelikelytobehigh,allowforfrequentairchanges.
2. Passiveventilationmaybeinadequatetocopewiththeproblemandtheinstallationoffan systemsshouldbeconsideredandincorporatedatthedesignstage.
3. ContactNewZealandSteelLimitedforspecialistadvice.
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PAGE
NINE
PROFILE BEND DIAMETERS ROOFING, WALL CLADDING AND ACCESSORIESPROFILE BEND DIAMETERS ROOFING, WALL CLADDING AND ACCESSORIES
NewZealandSteelLimitedproductsarecustomdesignedtoensuremaximumcompatibilitywiththeroll-formingprocess.Thepaintsystemsaredesignedtobedurableandadheretothemetal
substratesothattheyarenotaffectedbygoodroll-formingpractices.However,tighttensionbendsinthefinishedproductshouldbeavoidedassmallcracksmaybeformedwhichexposethemetal
substratetotheatmosphere.
For optimum corrosion performance no visible microcracing should be present in the
finished product. Therearemanyfactors,substrate,paint,benddiameterandformingpractice,
thataffectthetendencytomicrocrack.Therefore,itisnotpracticaltohaveafixedbenddiameterthatguaranteesnomicrocracking.
Mostproducts,formedinwelldesignedandoperatedequipment,willnothavemicrocracksattensionbends.Itisimportantthatvisualchecksformicrocrackingbemadeonthefinishedproducttoensureahighqualitystandardismaintained.
Productswithmicrocrackingonthetensionbendswillshowearliersignsofcorrosionwhenusedin
unwashedareasinsevereenvironments.
Design Guide:Design Guide:
1. Theuseofcorrugatedprofilesinsevereandspecialconditions(e.g.Geothermal)willhelpto
ensuregreaterdurability.
SOLAR HEATING PANELS OR RUBBER MATSSOLAR HEATING PANELS OR RUBBER MATS
Duringtheinstallationofsolarheatingsystems,careshouldbetakentopreventanydamageto
theroofingmaterial.Becauseofthehightemperaturescreatedandtheincreasedcondensationwhichmayresult,careshouldbetakentomaintainanairspacebetweentheroofandtheheatingunit.Followmanufacturersrecommendationsconcerningtubedirectionandtheuseoffixingsupport
brackets.
FailuretodothismayinvalidateaCOLORSTEELprepaintedsteelproductwarranty.
Design Guide:Design Guide:
1. Neverplaceheatingelementsorplumbingunitsdirectlyontheroofsurface.Followthesystemsuppliersrecommendationsconcerninginstallation.
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SWARF STAINING OF ROOFING AND CLADDINGSWARF STAINING OF ROOFING AND CLADDING
Swarfisthetermgiventosteeldebrisarisingfromcuttingorpiercingoperationswhenusingfrictionsaws,abrasivediscs,drillsetc.,onsteelroofingandcladdingproducts.Whilstcomprisingmostly
finesteelparticlesmixedwithabrasive,inthiscontextswarfmayalsobetakentoincludeanyotherdiscardedsteelobjectssuchasrivetshanks,nails,screwsandnuts,whichmaycomeintocontact
withcoatedproducts;ie:COLORSTEELprepaintedsteel,ZINCALUMEzinc/aluminiumalloy-coatedsteelandgalvanisedsteel.
Swarfparticles,ifleftonthesurface,willcorrodeandcauseruststainswhichwilldetractfrom
thefinishedappearanceofaproject.Thesestainsareoftenmistakenforearlydeteriorationoftheroofingandcladdingitself.
Design Guide:Design Guide:
1. Neverleaveswarfmaterialonthecoatedsurface.Followtherecommendationsincludedin theNewZealandSteelLimitedInstallersGuideorInformationBulletin7.
UNWASHED AREASUNWASHED AREAS
Whencontaminantssuchaswindblownsaltanddustaccumulateonpaintedsurfacesandbecomedamp,corrosionwilltakeplace.Manywindblowncontaminantsabsorbmoisturewhenexposedto
highhumidityandtheirpresenceonsteelacceleratescorrosion.
Forthisreason,areasonabuildingwhichareseldomwashedbyrainareparticularlypronetoearly
breakdownofthematerial.
Thiseffectmayfirstbenoticedasawhitecorrosionproduct,typicallyseenontheundersideofgutters,canopies,roofventsoronshelteredareasandtheundersideofprofilesusedhorizontallyaswallcladding.Itwillbemorenoticeablewheretighterradiusbendshavebeenusedinrollforming.
Evenoncoatedsteelwherecorrosionreactionsaremuchslower,thepresenceofcontaminantsoverlongperiodsoftimewillincreasetherateofcorrosion.
Themaintenanceregimesforunwashedareas,necessarytomeetthedurabilityrequirementsoftheBuildingCode,areshownonpages17and18ofthispublication.
WhentheundersideofZINCALUMEsteelandCOLORSTEELprepaintedsteelproductsis
exposedinanunwashedarea,e.g.:canopies,verandas,eaves,leantobuildingsetc.,additionalmaintenance,abovethatspecifiedonpages17and18,isrequiredtoensuresatisfactory
performanceoftheproduct.
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Design Guide:Design Guide:
1. Everyeffortmustbemadeduringthedesignofthebuildingtoeliminateorminimisesheltered
oroverhangingareas.
2. ConsiderationshouldbegivenduringthedesignstagetoensuretheundersideofZINCALUME
steelandCOLORSTEELprepaintedsteelisenclosedandthereforenotexposedtothe
environment.
3. Whereunwashedareascannotbedesignedout,specifyregularwashingoftheseareasas partofanongoingmaintenanceprogramme.Refertopages17and18forNewZealandSteel
Limitedrecommendations.
4. Designconsiderationforeasyaccessmustbegiventoareasthatrequireregularmaintenance.
5. EnsureprofilebendsarenottighterthanthoserecommendedundertheheadingofProfile
BendDiametersRoofing,WallCladdingandAccessories,andthattherearenomicrocracksinthefinishedproduct.
PAGE
ELEVEN
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WATER PONDINGWATER PONDING
RoofsRoofs
Wheretheroofpitchislow,changesinroofloadingsmayresultinanegativepitchandconsequentlyleadtowaterponding.WaterpondingisdetrimentaltotheperformanceofCOLORSTEELprepaintedsteelproducts.Thefollowingconditionscommonlycausewaterponding:
Over-spacedpurlins.
Deformationoftimberpurlins.
Placementofexternalloadssuchasairconditioningunits.
Rigidfixingonlongspanswhichcausesdeformationoftheprofileasaresultof thermalexpansion.
Design Guide:Design Guide:
1. Neveruseapitchoflessthan3degreesortheminimumrecommendedfortheprofile,whicheverisgreater.Pitchesoflessthanthisinvalidatethewarranty.
2. Designtheroofaccordingto theprofilemanufacturersspecifications.
3. Onminimumpitchroofs,ensurethatthegutterendofprofiledsheetsisturneddown.
4. Allowforthermalexpansiontopreventprofiledistortion.5. Considertheuseofwalkwaystopreventdamagewheretheroofmaybesubjecttoheavy
foottraffic.
6. Ensureroofpenetrationsdonotblocktheflowofwaterfromtheroof.
Note:PleaserefertoNewZealandSteelLimitedProductsandtheNewZealandBuildingCodeonpage13ofthispublicationunderE2/AS1ExternalMoisture
GuttersGutters
Guttersmustbeinstalledwithadequatefalltoensureallwateristransportedtoappropriately
locateddownpipes.Pondingoccurswhenwaterremainsinthegutterwhenthefallisinadequate.Overtime,thiscausesdegradationtothecoatingandultimatelyleadstogutterperforation.Perforationofthegutterasaconsequenceofinadequatefallorpondinginvalidatesboththe
manufacturerandproducerwarranties.Theinstallationanddownpipeconstructionshouldallowtheguttertodraincompletely.
Regularguttercleaningandmaintenanceisrequiredtoremoveleavesandotherdebristhatmay
restrictwaterflowtodownpipes.Particularcareshouldbetakenattheentrancetodownpipesandcorners,toavoidblockagesleadingtowaterponding.
Agutterprotectionsystem(oranyotherproduct)thatentrapswaterbetweenitselfandanysteel
productsurfaces,restrictingthecoatedsteelsabilitytodry,isnotrecommendedandisanexclusionintheproductwarranty.
WEATHERING OF COLORSTEELWEATHERING OF COLORSTEEL PRODUCTSPRODUCTS
Allbuildingproductswillweatherovertime.TheweatheringofCOLORSTEELprepaintedsteel
productswillresultinchangestoglossandcolour.Factorswhichinfluencethechangeareenvironmentalpollution,UVlevels,buildingorientationandpaintcolour.
Design Guide:Design Guide:
1. Whenaddingtoanexistingbuilding,considerationshouldbegiventotheweathered appearanceoftheCOLORSTEELprepaintedsteelproductsintheolderpartofthebuilding.
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NEW ZEALAND STEEL LIMITED PRODUCTS AND THENEW ZEALAND STEEL LIMITED PRODUCTS AND THE
NEW ZEALAND BUILDING CODENEW ZEALAND BUILDING CODE
The New Zealand Building Code defines durability requirements for many elements of buildings.These requirements are outlined in section B2 Durability. In general, most roofing and cladding is
required to last a minimum of 15 years (or a nominated period), to water penetration, but in somecases where the material has a structural function, the requirement may be for 50 years. This canbe achieved with suitable maintenance.
The New Zealand Building Code calls for durability performance which is relative to bothmaintenance and to working environments. The following information will assist specifiers to relatethese variables to New Zealand Steel Limited products.
CONFORMING WITH THE BUILDING CODECONFORMING WITH THE BUILDING CODE
ZINCALUME steel and the substrate used to produce COLORSTEEL prepainted steel products,have met the requirements of AS1397:2001 and are manufactured under a quality management
system to monitor ongoing compliance with this Standard. ZINCALUME steel has been appraisedby BRANZ as being suitable as feed stock for the manufacture of roof and wall cladding systems,
cladding accessories, spouting, downpipes and other rainwater goods.
EXTERNAL MOISTURE E2/AS1EXTERNAL MOISTURE E2/AS1
Adequate PitchAdequate Pitch
The New Zealand Building Code provides an Acceptable Solution to the problem of roof pitch.The pitch figures shown in paragraph 8.4.5 of Acceptable Solution E2/AS1 are reproduced, in part,below for your convenience.
Refer specific enquiries to the Profile Manufacturer who may have an Alternative Solution.
Source: New Zealand Building Code: Acceptable Solution E2/AS1
Note: Where manufacturers have more stringent requirements, these should be followed to optimiseperformance and to avoid invalidating guarantees.
OUTBREAK OF FIREOUTBREAK OF FIRE
ZINCALUME steel and COLORSTEEL prepainted steel need not be separated from flues and
chimneys. However, when formed into cladding products and associated accessories that are used inconjunction with or attached to heat sensitive materials, the heat sensitive material must be separatedfrom chimneys and flues in accordance with the requirements of NZBC Acceptable Solution C/AS1
Part 9 for the protection of combustible materials.
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ROOF PITCH REQUIREMENTS
Product Minimum Pitch
For profiled metal roof cladding Sheet Length 18m > 18m
Corrugated (with end laps present) 10 Refer manufacturer
Corrugated (no end laps present) 8 Refer manufacturer
Trapezoidal(where the crest height is less than 27mm) 4 Refer manufacturer
Trapezoidal(where the crest height is 27mm or higher) 3 Refer manufacturer
Trough profile 3 Refer manufacturer
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CONTROL OF EXTERNAL FIRE SPREADCONTROL OF EXTERNAL FIRE SPREAD
ZINCALUMEsteel and COLORSTEELprepainted steel formed into roof cladding profiles are suitable
for use as an external roof cladding in all purpose groups in accordance with NZBC Acceptable Solution
C/AS1 Paragraph 7.11.1.
ZINCALUMEsteel and COLORSTEELprepainted steel formed into wall cladding profiles are suitable
for use as an external wall cladding on all buildings in accordance with NZBC Acceptable Solution
C/AS1 Paragraph 7.11.2a. This statement is conditional on any applied surface finish being no more
than 1mm in thickness.
Specifiers should be familiar with the Acceptable Solution C/AS1 Part 7: Control of External Fire
Spread, which covers vertical and horizontal spread of fire.
MAINTENANCEMAINTENANCE
All roofing and cladding products are subject to the cumulative effects of weather, dust and other
deposits. Normal rain washing will remove most accumulated atmospheric contaminants from
roofs. For wall cladding, manual washing every 3 to 12 months, depending on the paint system,is recommended in moderate to very severe environments to prevent accumulation of dirt, debris
or other material not removed by rain washing. For areas that do not receive any or adequate rain
washing (called unwashed areas) such as soffits, wall cladding under eaves, underside of gutters,
fascias, sheltered areas of garage doors and unwashed roof areas, more extensive manual washing is
required. Similarly, other High Risk areas, around flues, under television aerials or overhanging trees
and sites prone to mould, lichen, bird droppings or debris, need to have regular manual washing.
Regular washing of COLORSTEEL prepainted steel products increases the durability by reducing
attack from airborne salts and pollutants. GALVSTEEL products and ZINCALUME steel products
will also benefit from routine washing.
COLORSTEEL prepainted steel surfaces should be manually washed with water and a sponge
or a soft nylon-bristled brush. For large areas it may be more appropriate to use water blasting at
pressures up to 20MPa.
Overpainting of COLORSTEEL prepainted steel products is discussed on Page 8 of this publication.
If New Zealand Steel Limited products are maintained according to the following
recommendations, the requirements of the New Zealand Building Code B2 for 15 year
durability for roofs and exterior walls will be met or exceeded.
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Note:
1. TheNewZealandBuildingCodedurabilityrequirementdoes notincludeaestheticappearance.
2. TheNewZealandBuildingCoderequiresadurabilityof15yearsminimum(withmaintenance)forroofing,includingvalleys,andwallcladdingproducts.Thismeansnomoisturepenetration duetoproductfailure.
3. TheNewZealandBuildingCoderequiresadurabilityof5yearsminimum(withmaintenance)forrainwaterproducts,guttersanddownpipes.Thismeansnoperforationduetoproductfailure.
4. NewZealandSteelLimitedproductsaredesignedtoexceedtheNewZealandBuildingCode
B2:durabilityrequirements.Continuedmaintenanceandoverpaintingwillgreatlyextend theultimatelifeofallproducts.
5. Wherea50yeardurabilityisrequiredORwhereaproductistobeusedinaggressiveinternalenvironments,NewZealandSteelLimitedshouldbeconsulted.
6. InIndustrialEnvironments,thetypeofpollutiongeneratedmayaltertheaboverecommendations.Ifindoubt,consultNewZealandSteelLimited.
ThefollowingmaintenanceinformationintheEnvironmentalChartisforguidanceonly.Eachproprietarybuildingproductshouldcarryitsownmanufacturersrecommendationsforusage.
NewZealandSteelLimitedwillnotacceptresponsibilityforproprietaryroofingandcladding
productswhichdonotconformtoourrecommendationsformanufacturing,environmentaluseormaintenance.
ENVIRONMENTAL CATEGORIES AND PRODUCT RECOMMENDATIONSENVIRONMENTAL CATEGORIES AND PRODUCT RECOMMENDATIONS
Important:Asproductuseisdictatedbylocalconditions,seekadvicefromyourroofingsupplieror
fixerforthebestNewZealandSteelLimitedproducttosuityourspecificenvironment.
ThefollowingfourpagespresentaguidetoNewZealandsenvironmentalcategories,theproducts
recommendedforspecificconditionsandresidentialroofingwarranties.
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FIFTEEN
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ENVIRONMENTAL CATEGORIES AND PRODUCT RECOMMENDATIONSENVIRONMENTAL CATEGORIES AND PRODUCT RECOMMENDATIONS
SEVERE ISO CATEGOR 4
Characterisedby: Lightsaltdeposits.
Afrequentsmellofsaltintheair.
Typicallystarts100-500metresfrombreakingsurfsuchasisfoundonexposedcoasts.
Intheimmediatevicinityoflargeexpansesofcalmsaltwatersuchasharbourforeshores.
Thisenvironmentmaybeextendedinlandbyprevailingwindsandlocalconditions.
VER SEVERE ISO CATEGOR 5
50mfromhighwateronEastCoast,100mfromhighwateronWestCoast.
Characterisedby: Heavysaltdeposits.
Thealmostconstantsmellofsaltsprayintheair.
Closetobreakingsurf(typically50-100metres)suchasisfoundonexposedcoasts.
Thisenvironmentmaybeextendedinlandbyprevailingwindsandlocalconditions.
COMMERCIAL WARRANTCOMMERCIAL WARRANT
Suchasschools,warehousesandbuildings,refertoNewZealandSteelLimitedfordetailsofcommercialwarranties.Maximumwarrantyofferedoncommercialbuildingsis15years.
IMPORTANTIMPORTANT
Asproductuseisdictatedbylocalconditions,seekadvicefromyourroofing
supplierorfixerforthebestNewZealandSteelLimitedproducttosuityourspecificenvironment.
Guttersshouldbeinstalledaccordingtomanufacturersinstructions.
Unwashedandhighriskareasmanualwashingevery3months.
INTRODUCTIONINTRODUCTION
NewZealandhasawiderangeofenvironmentalconditions,fromtheharshWestCoastbeaches,totherelativeshelteroftheWaikatofarmingregion.Therefore,NewZealandSteelLimitedoffersarangeofsteelproductswhicharesuitableformostlocations.
Roofing
Wall Cladding
Gutters/downpipes
Fascia
Roofing
Wall Cladding
Gutters/downpipes
Fascia
Roofing
Wall Cladding
Gutters/downpipes
Fascia
50metres0metres
MODERATE INLAND ISO CATEGOR 2
Characterisedby: Noobviousmarineorindustrialinfluences.
Typicallymorethan1000metresfromtheexposedcoastsormorethan500metresfromindustrialemissions.
MODERATE COASTAL ISO CATEGOR 3
Characterisedby: Littleornosaltdeposits.
Theoccasionalsmellofsaltintheair.
Typicallystarts500-1000metresfrombreakingsurfsuchasisfoundonexposedcoasts,ORintheimmediatevicinityofcalmsaltwatersuchasestuaries.
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VER SEVERE COASTAL SEVERE COASTAL
100metres 500metres
18 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.30 years:againstperforationasaresultofcorrosion.
15 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years: againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.10 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
15 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years: againstperforationasaresultofcorrosion.Not recommended
5 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.10 years:againstperforationasaresultofcorrosion.
5 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
Notrecommended
15 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.20 years: againstperforationasaresultofcorrosion.15 years: coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.10 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
15 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.30 years: againstperforationasaresultofcorrosion.
15 years: coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.10 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
15 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years: againstperforationasaresultofcorrosion.
15 years: coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.10 years:againstperforationasaresultofcorrosion.
10 years:coveringthepaintsurfaceagainstflaking,peelingandexcessivefade.15 years:againstperforationasaresultofcorrosion.
Notrecommended
Rainwashing
Rainwashingplusmanualwashingeveryyear.
Manualwashingevery6months.
Manualwashingevery6months.
Rainwashing
Rainwashingplusmanualwashingevery3months.
Manualwashingeverymonth.
Manualwashingeverymonth.
Rainwashing
Rainwashingplusmanualwashingeveryyear.
Manualwashingevery6months.
Manualwashingevery6months.
Rainwashing
Rainwashingplusmanualwashingevery6months.
Manualwashingevery3months.
Manualwashingevery3months.
Rainwashing
Rainwashingplusmanualwashingevery6months.
Manualwashingevery3months.
Manualwashingevery3months.
WARRANTIES MAINTENANCE WARRANTIES MAINTENANCE
Greaterthan50mfrombreakingsurfontheEastCoast.Greaterthan100mfrombreakingsurfontheWestCoast.
MODERATE COASTAL MODERATE INLAND
15 years: againstperforationasaresultofcorrosion.
15 years: againstperforationasaresultofcorrosion.
10 years: againstperforationasaresultofcorrosion.
10 years: againstperforationasaresultofcorrosion.
Notrecommended
Notrecommended
Rainwashing
Rainwashingplusmanualwashingevery6months.
Manualwashingevery3months.
Manualwashingevery3months.
Notrecommended
Notrecommended
WARRANTIES MAINTENANCE
Nowarrantyapplies
Notrecommended
Notrecommended
Rainwashing
Rainwashingplusmanualwashingevery6months.Paintingmaybeadvisabledependingonthespecificlocation.
Manualwashingevery3months.Paintingmaybeadvisabledependingonthespecificlocation.
Manualwashingevery3months.Paintingmaybeadvisabledependingonthespecificlocation.
Notrecommended
Notrecommended
WARRANTIES MAINTENANCE
1000metres
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SPECIAL ENVIRONMENTSSPECIAL ENVIRONMENTS
InNewZealandthereareareaswherelocalconditionscreateanincreasedlikelihoodofcorrosion.Specialconsiderationshouldbegiventomaterialselectionintheseareas.Theyinclude:
1. Geothermal Areas Hydrogensulphideassociatedwithgeothermalactivitycreatesacorrosiveenvironment.Variationsin
naturalactivityordraw-offfromsteamboresplustheeffectsofweatherconditionsmakethehighriskareashardtodefine.PleaseconsultNewZealandSteelLimitedforfurtherdetails.
2. West Coast, South Island
Inthisarea,smokefromthecoalburningfiresmaycausehighconcentrationsofsulphurdioxideintheair.ThecombinationofthisandthehighrainfallfortheregioncreatesanaggressivesituationwhichmustbeconsideredwhenchoosingtheappropriateCOLORSTEELprepaintedsteelcoating.Theeffectsofaseverecoastalenvironmentaggravatethesituation.
Thisareacombinesthemostseverefeaturesofbothindustrialandcoastalenvironments.PleasecontactyourlocalsupplierforthebestCOLORSTEELprepaintedsteelproducttouse.
3. Internal Environments Somecommercialoragriculturalapplicationsmaycreateinternalenvironmentsinwhichthebuild-upof
pollutantsorfumesisapotentialsourceofcorrosion.Similarlyacorrosiveenvironmentcandevelopwithinshedsusedforintensiveanimalfarming.PleaseconsultNewZealandSteelLimitedforfurtherdetails.
4. Industrial Environments Closetocorrosiveindustrialemissionsandsubjecttoheavyfalloutfromthem.Pleaseconsult
NewZealandSteelLimitedforfurtherdetails.
Further Assistance
FurtheradviceontheselectionoftheappropriateproducttosuityourparticularlocationcanbeobtainedfromNewZealandSteelLimitedoryourlocalCOLORSTEELprepaintedsteelsupplier.
VER SEVERE SPECIAL ENVIRONMENTS
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COMMERCIAL WARRANTIESCOMMERCIAL WARRANTIES
CommercialwarrantiesareissuedthroughtheRollformerbyNewZealandSteelLimitedandthetermsarespecifictoeachcontract.
Inordertoensuretheappropriateproductisspecifiedfortheintendedservicelifeinanygivenenvironment,NewZealandSteelLimitediskeentobeconsultedasearlyaspossibleinthedesignstagetoensurecorrectmaterialselectionandbackingbyanappropriatewarranty.
WarrantyapplicationsaregenerallymadethroughtheroofingmanufacturerandwarrantyperiodsandconditionsareassessedbyNewZealandSteelLimited.
Factorssuchasroofdesign,roofpitch,profile,coatingtype,internalandexternalenvironmentsandspecialconditions(suchasrequirementforCleaninPlace)areallassessedatthetimeofthewarrantyapplication.Maintenancerequirementswillbespecifiedaspartofthewarranty.
DraftwarrantiesareavailablefromNewZealandSteelLimitedtosupporttendersforspecificprojects.Thetermsandconditionsofthedraftwillremainunchangedprovidingthatthetermsoftheprojectareunaltered.
Awarrantyisissuedonthesatisfactorycompletionofthecontract.InstallationmustbecarriedoutinaccordancewithNewZealandSteelLimitedsrequirementsandaccordingtogoodtradepracticesasdetailedintheMetalRoofingandWallCladdingCodeofPractice.
AsiteinspectionbyNewZealandSteelLimitedmaybecarriedoutpriortotheissuingofanywarranty.
Themaintenanceprogrammespecifiedinthewarrantymustbecompliedwithtovalidatethewarranty.
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INSTALLATION INFORMATIONINSTALLATION INFORMATION
DetailsrelatingtotheinstallationofallproductsareprovidedintheInstallersGuide.ThisbookletcoversNewZealandSteelLimitedsrecommendationsforhandling,cutting,fixing,sealing,sitestorage,etc.AdditionalcopiesofthispublicationmaybeobtainedfromNewZealandSteelLimited.
INFORMATION TO HELP OU AVOID PROBLEMSINFORMATION TO HELP OU AVOID PROBLEMS
Inalmostallapplications,ZINCALUMEcoatedsteelandCOLORSTEELprepaintedsteelwillout-performgalvanisedsteel.Therearehowever,asmallnumberofapplicationsforwhichgalvanisedsteelismoresuitable.
ZINCALUME coated steel and COLORSTEEL prepainted steel products must not be used for:
Formworkincontactwithwetconcrete.
Productstobeembeddedinconcrete.However,whereverysmallvolumesof
concreteareinvolved(e.g.splashes)whichareabletocurequickly,thereislittle corrosiveeffect.
Fertiliserstorageshedsandcontainers.
Culverts,orwhereZINCALUMEcoatedsteelmaterialisburiedintheground.
Watertanks.
Highlyalkalineenvironments(e.g.cementmanufacture).
Coolroomproducts.
Buildingsforintensiveanimalfarming.
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TECHNICAL FEATURESTECHNICAL FEATURES
CORROSION PROTECTIONCORROSION PROTECTION
Thelongestablishedmethodofprotectingsteelagainstcorrosionhasbeentoapplyacoatingof
zinc(galvanising).Thezincsurfaceformsahard,imperviouslayerwhichlimitsfurthercorrosion.Thisprovidesforthelongevityofperformancewhichwehavecometoexpectfromgalvanisedsteelproducts.
Thezinccoatingalsopossessesanotherveryusefulproperty.Smallexposedsurfacesoftheunderlyingsteelsuchasscratchesorcutedgesdonotcorrodebecauseofaneffectknownas
sacrificialprotection.
ZINCALUMEsteel,azinc/aluminiumalloycoating,providesasuperiorperformancetothatof
galvanisedsteel.Itcombinesthebarrierprotectionofaluminiumandthesacrificialprotectionofzinc,thusgivingthebestofbothworlds.
Itfollowsthatbycoatingthesesubstrateswithanaddedpaintsystem,thesteelcorewillbeprotectedforalongerperiod.ItisforthisreasonthattheCOLORSTEELprepaintedsteelcoating
systemsweredeveloped.Eachcoatingisdesignedtoprotectthesubstratefromspecificenvironmentalconditions.
Cross Section of ZINCALUMECross Section of ZINCALUME Coated SteelCoated Steel
UV PROTECTIONUV PROTECTION
NewZealandexperiencessomeofthemostextremeUVconditionsintheworld.UVlightcancausebreakdownoftheresinusedinsomepaints.Thisleadstoerosionandchalkingofthepaint
film.UVlightcanalsocausethebreakdownofpigments(particularlyorganicbasedpigments)resultinginfading.
Inresponsetothisthreat,anon-goingprogrammeofproductimprovementhasledtotheformulationofthecurrentCOLORSTEELprepaintedsteelpaintsystems.Thesesystemsutilisepigmentsandresinswhichhavebeenselectedfortheircolourstability,flexibilityanddurability.
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ZINCALUME
Steel Cladding.
PROFILE DESIGN INFORMATIONPROFILE DESIGN INFORMATION
Specificationsrelatingtoroofingandcladdingprofilesandpricingdetailsshouldbesoughtfromthespecialistroofingmanufacturersconcerned.New Zealand Steel Limited does not provide a
rollforming service.
ProfiledesignsfromyourlocalsupplierwillspecifythegradeandBMTappropriatetoanycontract.
DefinitionsDefinitions
1. BMT:Basemetalthicknessisthethicknessoftheuncoatedsteelcore.Thefinishedthickness ofthematerialwillincreasebytheaccumulationofcoatingsduringmanufactureby
NewZealandSteelLimited.
2. Grade:Themechanicalstrengthofthesteelsubstrateisexpressedinyieldstrengthvalues
measuredinMPa.LowstrengthsteelmayberatedasG1,G250orG300.Astheyield strengthofthematerialincreases,sodothevalues,sothatG550hasthehigheststrength.
3. Span:Thedistancebetweenpurlins,asrecommendedbytheRollformerforeachparticularprofile.
HOW TO SPECIFY NEW ZEALAND STEEL LIMITEDHOW TO SPECIFY NEW ZEALAND STEEL LIMITEDROOFING AND CLADDING PRODUCTSROOFING AND CLADDING PRODUCTS
Product(ZINCALUME,GALVSTEEL,COLORSTEELENDURA,COLORSTEELMAXX)
Profi le
Colour(Whereapplicable)
BMT(eg:0.40or0.55mm)
Grade(eg:G300orG550)
FURTHER COATING/SURFACE OPTIONSFURTHER COATING/SURFACE OPTIONS
InadditiontotheproductsmakingupthestandardCOLORSTEEL prepaintedsteelproductrange,NewZealandSteelLimitedproducenon-standardcoatingsforspecialapplications(eg:highreflectancefinishes).ForspecialisedoptionspleasecontactNewZealandSteelLimited.
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S P E C I F I E R S A N D B U I L D E R S G U I D E
NewZealandSteelLimited,PrivateBag92121,Auckland1142,NewZealand. Ph0-9-3758999 Fax0-9-3758213
NOTE: WithNewZealandSteelLimitedscommitmenttocontinuousimprovement,informationprovidedinthispublicationmaybesubjecttomodification.Atthetimeofpublicationwebelievetheinformationcontainedinthisdocumentisthebestavailable.Nonetheless,wereservetherighttomodifyanyproduct,technique,equipmentorstatementtoreflectimprovementsinthemanufactureandapplicationofcoilcoatedproducts.TheinformationissuppliedwithoutprejudicetoNewZealandSteelLimitedsstandardtermsandconditionsofsale.Intheeventofanyconflictbetweenthisinformationandthestandardtermsandconditions,thestandardtermsandconditionsshallprevail.
ThiseditionoftheNewZealandSteelSpecifiersandBuildersGuidesupersedesallpreviouseditions.
Copyright2010NewZealandSteelLimited.
FURTHER INFORMATION
Foradditionalinformation,literatureortechnicalassistance,pleasecontact:
COLORSTEELandZINCALUMEMarketingNewZealandSteelLimited PrivateBag92121,Auckland1142
Telephone:0-9-3758999
Facsimile:0-9-3758213FreePhone:0800100523
EmailAddress:[email protected]://www.colorsteel.co.nz
GALVSTEELisatrademarkofNewZealandSteelLimited.
COLORSTEELisaregisteredtrademarkofNewZealandSteelLimited.
MAXXisatrademarkofNewZealandSteelLimited.
isaregisteredtrademarkofNewZealandSteelLimited.
ENDURAisatrademarkofNewZealandSteelLimited.ZINCALUMEisaregisteredtrademark
ofBlueScopeSteelLimited.
AXXISisaregisteredtrademarkofNewZealandSteelLimited.