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EnergyandBuildings68(2014)254–269ContentslistsavailableatScienceDirectEnergyandBuildingsjournalhomepage:∗,MattiaMercanzin,DarioTrabuccoUniversitàIUAVdiVenezia–DipartimentoArchitetturaCostruzioneConservazione,exConventodelleTerese,Dorsoduro2206,Venice30135,ItalyarticleinfoabstractArticlehistory:Received23July2013Receivedinrevisedform23August2013Accepted2September2013Keywords:EmbodiedenergyEnvironmentalresourcesFloortypesFramepluscoreSustainableskyscraperTallbuildingsThispaperdealswiththeenvironmentalresourcesconsumedtoconstructtallbuildingstructures;theconsumptionismeasuredbytheenergyrequiredtoobtaintallbuildingstructuresandisexpressedintermsofcradle-to-gateembodiedenergy.Areferencestructurecomposedofcentralcore(madeofreinforcedconcrete)andrigidframes(madeofeitherreinforcedconcreteorsteel)isconsidered.Thereferencestructureisdimensionedanddetailedforbuildingsfrom20to70stories;theembodiedenergyofeachbuildingisthenestimated(total,ofthecomponents,pernetrentablearea).Theresultsshowthat,ifsomedesigndecisionsaredictatedbytheembodiedenergy,thepremiumforheightoftheembodiedenergyisnotsubstantial,whichprovesthattallbuildingstructurescanbesustainable.However,astructurewiththelowestweightdoesnotimplythelowestembodiedenergy.Theresultsalsoprovethattheembodiedenergydependsmainlyontheflooringsystem,andthatsteelconsumesmoreembodiedenergythanReinforcedConcrete.Ultimately,theembodiedenergyisconfirmedtobeaviabletooltodesignsustainabletallbuildings,andtheresultspresentedhereinmayaddressdesigntowardminimizingtheembodiedenergy,whichmeanstosaveenvironmentalresources.©2013ElsevierB.V.Allrightsreserved.1.IntroductionThispaperdealswiththeenergyconsumedtoconstructtallbuildingstructuresandaimstoaddressthedesignoftallbuildingstowardssavingenvironmentalresources.Tallbuildingsareoftenbelievedtobenon-sustainable,mainlyduetothelargeamountofmaterialsrequiredforthestructure.Ahigh-risebuildingrequiresawind-loadresistingsystem,whilelow-risebuildingsmayresistthewindloadwithalmostthegravity-loadresistingsystemonly.Moreover,high-risebuildingsrequireagravity-loadresistingsystemwithheaviercomponents(especiallyatthelowerstories)thanlow-risebuildings.However,thegreateramountofmaterialrequiredbyhigh-risewithrespecttolow-risestructures(premiumforheight)dependsmainlyonthewind-loadresistingsystem.Theenvironmentalresourcesconsumedtoconstructatallbuild-ingstructuremaynotbeexpressedjustbytheamountofmaterialthatisused,butalsobytheenergythatisconsumedtoobtainthestructure.Amethodtomeasuretheenergyconsumptionduringtheproductionofmaterialsandconstructionistousetheembodiedenergy(EE)[1–24].∗Correspondingauthor.Tel.:+390412571289;fax:+39051392909.E-mailaddress:paofor@iuav.it(P.Foraboschi).2.Embodiedenergy:definitionandapplicationAtpresent,thereareseveraldefinitionsofEE,andeachdefi-nitionimpliesadifferentmethodtocalculatetheEE.Conversely,auniquedefinition,andhenceauniqueestimationmethod,hasnotyetmettheconsensusofthescientificcommunityworldwide[3,5,9,21,25,26].TheEEcanbedefinedasthesumofalltheenergyconsumedduringthelifecycleofproductsandservices;accordingly[27],theEEistheenergyconsumedtoproduceeverymaterialthatcomposestheanalyzedobject.Anotherdefinitionisthat[28]“thetotalembodiedenergycom-prisesthedirectenergypurchasedtosupporttheprocessunderconsiderationplustheindirectenergyembodiedininputstotheprocess”.ISO14040:2006standard[29],whichdescribesthestepsofalifecycleassessment,suggeststheideaofanalternativedefinition;however,thisdefinitionarisesmanyerrorsandomissionsariseifthesuggesteddefinitionisused[30].Hence,accordingtothechosendefinition,andconsequentlytotherelatedestimationmethod,differentvaluesofEEcanbeobtainedforthesameobject[3,5,21,25–27,31].Thisresearchusestheapproachdescribedinthe“InventoryofCarbonandEnergy”(ICE)[32],whichhasaconsiderabledegreeofconsensus.Accordingly,inthispaper,theenergyconsumptionis0378-7788/$–seefrontmatter©2013ElsevierB.V.Allrightsreserved.(2014)254–269255measuredbyusingtheEEvaluescontainedintheICEopensourcedatabase.Hereafter,theEEistakenas[32]thetotalprimaryenergyconsumedfromdirectandindirectprocessesassociatedwithaproductorservice,andwithindefinedboundarieswhichdefinewhatisandwhatisnotincludedwithinthedatabase.TheICEopensourcedatabasehastheboundariesofcradle-to-gate.Thisincludesallactivitiesfrommaterialextraction,manufacturing,assembling,transportation,andrightthroughtofabricationprocessesuntiltheproductisreadytoleavethefinalfactorygate.TheauthorsoftheICEdatabasehaveexcludedtheactivitiesbeyondthefactorygatebecausetheyclaimthattheexpansionoftheboundariestoincludethedelivertothesiteofuse(cradle-to-site)ortheendofthelifeprocess(cradle-to-grave)wouldmodifythecradle-to-gatevaluesonlymarginally.Althoughnewstudiescallthisbeliefintoquestion[33,34],thisresearchconsiderstheICEdatabase–cradle-to-gateEEvalues–sincetheEEowingtotrans-portationofmaterialsandcomponentstothebuilding