b'GWP=Material Quantity X CarbonForinstance,instructuralsteel,theBylaw 2025 (City of Vancouver, 2022; City of Factor (kgCO 2 e/unit)=Embodied CarbonlargestcarboncontributionisfromtheVancouver, 2023; City of Vancouver, 2024) (kgCO 2 e) process of converting the raw materialshasalreadyestablishedabenchmark Thisisausefuloversimplificationinto steel. The carbon factors for materialsof 400 kgCO 2 e/m2 based on gross floor because,referringtoFigure1,theare reported through environmentalarea and considering all wbLCA modules largestcontributortoGWPisfromtheproductdeclarations(EPDs)forthe(referred to as VBBL-1 in this article). Then productstage(A1-A3).Therefore,thisproductstageofthewbLCA(A1-A3).we denote VBBL-2 as 95 per cent of the basic form provides insight into the heartOrganizations such as the CISC producebenchmark (380 kgCO 2 e/m2) and VBBL-of the issue for structural materials andindustryaverageEPDsforavarietyof3 as 90 per cent of the benchmark (360 opportunitiesforreducingembodiedstructural steel products used in Canada;kgCO 2 e/m2).carbon. Material quantities are a functionsee Table 1 for an example of some ofMoving eastwards, the Toronto Green ofthebuildingtype,occupancyandtheEPDsusedinthestudy.EPDsareStandard version 4 (TGS v4) for mid- to thestructuralsystems.Appropriatelyimportantbecausetheyprovidethehigh-riseresidentialandnon-residential selecting the functional requirements, theprojectteamwiththeopportunitytobuildings (City of Toronto, 2025) sets out structural system, the building envelopeevaluate the carbon impact of differentthe following limits: Tier 1 is the mandatory and the amount of parking are the firstproducts and material types. performance level, which currently has no opportunitiestoreduceembodiedTable1showsthethreedifferentGWP intensity target in version 4, and Tier carbon. Simply, using less in structuralscenariosthatwereinvestigatedin2andTier3areoptionalperformance and envelope systems typically results inthereport.TheBaselinescenariouseslevels.ProjectspursuingTier2must lower carbon and lower-cost buildings. industry average EPDs, Scenario 1 is thedemonstrate a GWP intensity of less than However,urgentactionrequiresuslowestcarboncase,andScenario2350 kgCO 2 e/m2 based on built floor area tochallengethestatusquo.Reducingisacasewherethehot-rolledshapesconsidering the A1-3 module, and likewise materialusecanonlytakeyousofarare sourced solely from a basic oxygenthe Tier 3 limit is 250 kgCO 2 e/m2.along the path to net-zero carbon whilefurnaceproductionprocess.BaselineSimply put, embodied carbon is rapidly balancingsocietysneedforthebuiltvaluesareassumedforthebuildingbecominganewdesignparameter environment. In this regard, the carbonenvelopeandotherstructuralmaterialsthatisintegraltocompletingprojects factor in the equation above is anotherregardless of the scenario. in Canada.tool we can use to reduce carbon. TheAsnotedearlier,therearealready carbonfactorrepresentshowmuchembodiedcarbontargetsspecifiedbyRESULTS OF THE STUDY carbon is released from the productionCanadianmunicipalities.OnthewestWith that background in hand, lets dive process of a specific material. coast, the Proposed Vancouver Buildinginto some results from the study! A short TABLE 1 : Overview of the steel EPDs selected for this study.Steel Element Type Scenario EPD Provider A1-A3 (kgCO 2 e/t)Hot-Rolled ShapesBaseline CISC Industry Average (CISC, 2021) 1,170(W, S, I) Scenario 1 Gerdau: Petersburg, VA (Gerdau, 2022) 680Scenario 2 WORLD BOF (British Steel, 2020) 2,450CISC Industry Average (CISC, 2021) 1,860Hollow StructuralBaseline ArcelorMittal Dofasco(1) (ArcelorMittal Dofasco, 2023) 1,070Steel Shapes (HSS) Scenario 1, 2 NucorChicago (Alliance Steel Fabrication, 2023) 1,170Steel Plate Baseline CISC Industry Average (CISC, 2021) 1,710Scenario 1, 2 EVRAZ (Regina) (EVRAZ, 2023) 950Cold-Formed SteelBaseline CISC Industry Average (CSSBI, 2022) 2,430(Steel Deck) Scenario 1, 2 ArcelorMittal Dofasco Xcarb (ArcelorMittal Dofasco, 2023) 1,260Baseline SJI Industry Average (Steel Joist Institute, 2022) 1,430Joists (OWSJ) Scenario 1, 2 Nucor Joists (Nucor, 2022) 8402Merchant BarBaseline CISC Industry Average (CISC, 2021) 1,720Quality (C, L) Scenario 1, 2 NucorSeattle (Nucor, 2022) 530Rebar Baseline CRSI (CRSI, 2022) 850Scenario 1, 2 Cascade Steel Rolling Mills, Inc. (Cascade Steel Rolling Mills Inc., 2022) 440(1)Indicates that this EPD was selected for Scenario 1 & 2. At the time of publication, HSS is currently being produced on aproject-by-project basis using this material. HSS is also being currently manufactured by Nucor at a similar GWP.(2)Nucor Vulcraft released a new EPD subsequent to the analysis in this report with a GWP of 757 kg CO 2 e/m2 (Vulcraft Canada, 2024).ADVANTAGE STEEL WINTER 2025|17'