Embodied Carbon Research Articles

<p>This study evaluates the eco-efficiency of mortars incorporating three types of limestone fillers (LF): quarry limestone dust (QLD), commercial limestone filler (CLF), and laboratory-ground limestone powder (GLP). Sustainability metrics considered include embodied energy (EE), embodied carbon (EC), material cost, which were normalized to compressive strength and rheological performance, as well as particulate matter emissions (TSP, PM<sub>10</sub>, PM<sub>2.5</sub>). Results show that GLP, owing to its high purity confirmed by FTIR and XRD, achieves the best eco-efficiency, with lower EE, EC, and cost per MPa compared to QLD and CLF. QLD substitution up to 20% in crushed sand (CS) mixtures progressively reduced particulate emissions, reflecting its by-product status with no additional processing. While PM<sub>2.5</sub> reductions were modest, notable decreases in PM<sub>10</sub> and TSP highlight the mitigation of coarse dust emissions from CS processing. Even with the added cost of Sp, incorporating up to 15 wt% QLD while maintaining constant slump remains a balanced strategy. The eco-indices further confirm that optimal performance is obtained around 10–15% QLD substitution, where both environmental and mechanical efficiencies converge. Overall, the findings underscore that filler selection and treatment should be guided by both technical performance and environmental outcomes, aligning material efficiency with improved air quality indicators.</p>

Geosynthetic products are widely used in construction projects. Although many studies have demonstrated that geosynthetic solutions result in lower carbon dioxide emissions compared to traditional methods, precise embodied carbon (EC) values for geosynthetic products are scarce. In addition, the EC values of geosynthetics are sometimes substituted with primary raw material data in project carbon footprint calculations, which undermines the credibility of their sustainability claims. This paper reviews EC calculation methods for geosynthetics and provides a geogrid case example. It then extracts EC values from 120 Environmental Product Declarations (EPDs) to propose representative values for geosynthetic products in different regions and recalculates the carbon footprints of geosynthetic-reinforced projects using maximum EC values to assess their impact on project-level estimates. The results show that emissions accumulated during the manufacturing stage of geosynthetic products account for nearly 30% of their total EC. However, the EC of geosynthetic products contributes only a small portion of the total EC of geosynthetic-reinforced projects. Even with higher EC values, geosynthetic solutions remain more sustainable than conventional alternatives. The calculation method presented in this paper enables geosynthetic companies to estimate product EC without commercial life cycle assessment software, while EPD-derived values enhance existing datasets for more accurate carbon footprint calculations in geosynthetic-reinforced projects globally.

The construction industry is facing increasing pressure to reduce the embodied carbon, particularly in structural steel systems, which contributes significantly to the global Greenhouse Gas (GHG) emissions. As a potential solution, castellated beams offer enhanced structural efficiency through web openings that increase stiffness while reducing the material usage. This study investigated the application of castellated beams as secondary structural members and evaluated their Embodied Carbon (EC) performance in comparison with that of conventional I-beams. A simply supported beam with a 12 m span was analyzed under typical floor loads. The structural performance was assessed based on the strength and deflection criteria using the American Institute of Steel Construction (AISC) design provisions, whereas the EC was calculated using a cradle-to-gate approach. The results demonstrate that the castellated beam (CB18×14) meets all the structural requirements and exhibits superior deflection performance compared to the conventional W14×22 I-beam. Moreover, the castellated beam achieved a 27% reduction in EC per linear foot, highlighting its potential as a sustainable alternative to steel-framed buildings. These findings emphasize the dual benefits of castellated beams in enhancing the structural performance and reducing the environmental impact in secondary beam applications.

Abstract The construction sector accounts for approximately 11% of global greenhouse gas emissions, largely due to the production of steel, concrete and aluminum. As global infrastructure investments grow, exceeding $2.9 trillion in the United States alone, there is an urgent need to transition to low-carbon structural systems. Mass timber offers a promising alternative, with lower embodied carbon (EC) and the potential to function as a carbon sink when sustainably sourced. However, conventional mass timber floor systems are limited to spans of 16–25 feet, depending on the selected system and thickness. They often rely on concrete toppings for acoustic and vibration performance, undermining environmental and circularity benefits. Here, we present a novel, all-wood mass timber floor system capable of spanning 40 feet, comparable to steel-framed construction, while achieving carbon negativity, modularity, and disassembly. This is the first timber-based system to combine these structural and sustainability attributes at this span-length. A cradle-to-gate life cycle assessment, aligned with EN 15978 and ISO 14044, quantified the floor system development environmental performance across two proprietary connection strategies: adhesive + screw and sharp plate + screw. Each design sequestered 4,787 kg CO2-eq of biogenic carbon per functional unit, contributing to a net EC of −100.6 and −96.7 kg CO2-eq/m2, respectively, after accounting for construction-stage emissions. The Sharp Plate system also showed lower impacts in smog formation, ecotoxicity, and energy use. Our findings demonstrate the viability of long-span, low-carbon timber floor systems and highlight how connection design can meaningfully influence environmental performance in timber-floor design.

Abstract This study aims to provide a comprehensive understanding on the quantitative study on indirect energy-related emissions, so called embodied carbon in housing development projects using Life Cycle Assessment (LCA) approach. The assessment was carried out based on a residential housing development project in Malaysia, with a gross floor area of 92,903 m². The assessment focused on the cradle-to-site phase of the building lifecycle, excluding on-site waste generation. Results revealed that a single residential unit accounted for 68.60 tCO2e (0.738 tCO2e/m2). The primary contributors to embodied carbon from material manufacturing were steel (38.12%), bricks (15.26%), and concrete (14.16%). The findings suggest that embodied carbon can be significantly reduced by sourcing materials locally within a 200 km radius, which alone could reduce material transportation emissions by 11%. The proposed LCA framework offers a practical reference for Malaysian construction companies to initiate early-stage embodied carbon assessments, potentially advancing sustainable residential building practice.

As part of the global sustainability efforts, the construction industry is facing an increasing pressure to reduce its environmental impact, particularly in terms of Embodied Carbon (EC) emissions. Steel, a critical material in modern construction, contributes significantly to these emissions owing to its carbon-intensive production process. This study investigated the potential of tapered steel members as sustainable alternatives to standard I-beams in gable steel frame structures, focusing on reducing the EC and improving the overall structural efficiency. This study evaluates the structural performance, embodied carbon, and cost implications of tapered members compared to standard I-beams across different span lengths. The results show that the tapered steel members can achieve up to a 22% reduction EC compared to the standard I-beams while also providing higher design efficiency. These benefits became more pronounced as the span width increased. From a cost perspective, the tapered members offer savings for shorter spans; however, for longer spans, the increased fabrication complexity may offset the material and carbon reductions. This study contributes to the growing body of knowledge on sustainable structural design by emphasizing the importance of the material optimization and environmental impact reduction in the construction industry.

The construction sector is a major contributor to greenhouse gas emissions, yet the role of embodied carbon (EC) emissions associated with materials and construction processes remains under-addressed, particularly in Malaysia. This paper reviews current practices, challenges, and methodologies for assessing EC in the Malaysian construction industry. It highlights the dominance of operational carbon in regulatory reporting and the limited industry-wide adoption of embodied carbon evaluation, largely due to data gaps, lack of awareness, and implementation barriers. Drawing on local and international studies, the paper explores assessment methods such as Life Cycle Assessment (LCA), Input-Output LCA, and hybrid approaches. It evaluates the implications of building design systems, especially the role of Industrialized Building Systems (IBS), in reducing EC. The findings stress the need for standardized EC data, stronger policy enforcement, and industry collaboration to support Malaysia’s transition toward sustainable, low-carbon construction.

The building and construction sector is a major contributor to global carbon emissions, with Embodied Carbon (EC) from material production, transportation, and construction gaining increasing attention. Although seismic design enhances structural safety, it also leads to a higher material consumption, thereby increasing the EC footprint of the buildings. This study examines the impact of seismic design on EC in steel buildings, focusing on columns, beams, and floors. A two-story steel-framed building was analyzed under low, moderate, and high seismic intensities. The EC assessment followed BS EN 15978, considering cradle-to-gate emissions (stages A1–A3) using industry-standard Inventory of Carbon and Energy (ICE) database values. Structural modeling was conducted using ETABS to determine the material demands. The results showed that the total EC increased by approximately 51% from non-seismic to high seismic conditions. Columns and beams exhibited the highest proportional increase owing to the larger cross-sectional sizes required for seismic stability, while concrete slabs contributed the most absolute emissions. Steel components, however, exhibited the greatest relative rise in carbon intensity. To reduce the EC in seismic design, structural optimization methods, high-strength steel utilization, and material reuse strategies should be explored. This study provides a scientific foundation for integrating sustainability into seismic regulations, thus contributing to low-carbon structural solutions for earthquake-prone regions.

ABSTRACT Upfront carbon emissions of buildings encompass all greenhouse gas emissions linked to building materials extraction, manufacturing, transportation, and installation processes. Many countries face barriers in calculating and reducing the upfront carbon emissions of buildings during the design stage due to unreliable materials embodied carbon (EC) data, inconsistent methods, and tool complexity. Therefore, the current study aims to develop a national adaptable methodology with a simple tool for calculating and reducing buildings’ upfront carbon emissions based on a reliable regional EC dataset. To validate the developed methodology and tool, a group of architecture firms in Ireland used it to calculate and reduce the upfront carbon emissions of their projects. Fourteen buildings representing six typologies were evaluated, and on average, the results were 436 and 648 kgCO2e/m2 for residential and non-residential buildings, respectively. The calculation method and tool have been validated since the upfront carbon emissions values align with the averages of buildings in Europe. The reduction methodology was developed using the materials’ substitution strategy to replace in-situ concrete, steel, insulation, and window frames with lower-EC alternatives. The substitutions reduced the upfront carbon emissions of the residential and non-residential case studies by 21% and 23.8% on average, achieving the Irish government's 2030 Climate Action Plan. The future development of the reduction methodology can go further by considering more key materials.

Increasing construction and demolition waste (CDW) disposal issues in landfills necessitate exploring sustainable solutions in developing nations like Nepal. The reason for this investigation is to assess the sustainability of natural coarse aggregate (NCA) and recycled concrete aggregate (RCA) and examine the practicality of recycled aggregate concrete in the Kathmandu Valley. This sustainability evaluation of RCA and NCA is carried out through qualitative and quantitative assessment across social, environmental, economic, and technical terms. The study uses NCA of Naubise and Dolalghat (nearby quarry sites), and RCA from crushed concrete debris. A total of 28 sub-criteria are identified for the study: 25-qualitative and 3-quantitative. Qualitative analysis is based on a two-level questionnaire survey where experts rate the importance level and scores for each qualitative sub-criteria, whereas the quantitative analysis evaluates the score of sub-criteria: embodied energy (EE), embodied carbon (EC) and strength. The EE and EC values are derived from literature review and primary data, while strength scores are assigned based on the aggregate physical and mechanical properties. The sustainability index is determined by aggregating the scores across all criteria. The results show a sustainability index of 0.872 for NCA and 0.96 for RCA, suggesting that RCAs are socially acceptable, environmentally safe, and economically and technically viable. The study further evaluates the strength of 24 concrete specimens with varying replacement percentages of RCA (0%, 25%, 30% and 50%) for NCA. The results suggest that replacing up to 50% of NCA with RCA achieves a comparable strength to conventional concrete.

Maritime carbon responsibility allocation can guide sea level rise and storm surge mitigation in BRICS coastal zones by addressing emissions-driven climate risks. This study analyzes the characteristics of and differences in embodied carbon emissions in the Maritime Transport Industry of the BRICS countries from the perspectives of producer responsibility, consumer responsibility, and shared responsibility, based on a global value chain framework. Using non-competitive input–output data from the OECD and introducing a processing trade adjustment mechanism, the study calculates the carbon emissions of the five countries from 1995 to 2018. The empirical results show that under producer responsibility, carbon emissions in China and South Africa’s maritime transport sectors are mainly driven by exports, with production-side emissions significantly higher than consumption-side emissions. Under consumer responsibility, emissions in India and Brazil are driven by the demand for imported goods, reflecting their high reliance on external markets. In shared responsibility accounting, China’s cumulative carbon emissions account for 66.81% of the total emissions from the five countries, highlighting its central role in global supply chains. The study also finds that the differences in carbon emissions among the countries are mainly due to differences in economic structures, trade dependencies, and consumption patterns. Different responsibility accounting methods have a significant impact on carbon emissions, with export-oriented countries tending to weaken producer responsibility, while import-oriented countries seek to avoid consumer responsibility. The shared responsibility mechanism, through the dynamic allocation coefficient α, provides a practical approach to balancing efficiency and equity in global carbon governance.

Breaking the strong connection between economic growth and carbon emissions is crucial for China to achieve high-quality, sustainable development. Neglecting the carbon emissions embedded in interregional trade risks inflating the perceived progress in decoupling, however, as emissions are often shifted between regions through trade. This research evaluates the decoupling of carbon emissions from economic growth, considering the embodied carbon flow, and decomposes its factors across thirty Chinese provinces from 2002 to 2017. We found that China’s carbon emissions surged from 3,641.47 Mt to 7,828.88 Mt during the study period, growing at an annual average rate of 5.76 percent. There was a noticeable shift in embodied carbon flow from less affluent or resource-intensive provinces to more developed areas. Sectoral analysis indicated that these developed provinces outsourced their carbon emissions, associated with low-value-added raw materials and intermediate goods, to less developed provinces to achieve emissions reductions. Decoupling analysis indicated that the majority of provinces consistently showed weak decoupling, but some transitioned to strong decoupling. By 2017, twelve provinces achieved production-based decoupling, thirteen reached consumption-based decoupling, and seven regions, including Shanghai, Beijing, and Guangdong, realized “double decoupling.” Conversely, areas like Zhejiang and Sichuan attained production-based decoupling, but their consumption-based emissions continued to rise. Structural decomposition analysis indicated that optimizing the production structure and curbing energy-intensive consumption emerge as primary factors in enhancing the decoupling status across various regions. Although international trade is not considered, these results still highlight the importance of accounting for embodied carbon flows in interregional trade when assessing decoupling targets. This provides a theoretical basis for the development of differentiated decoupling policies.

Purpose With the use of increased number of measures and strategies towards mitigating operational carbon emissions, a greater emphasis has now been placed on reducing the resultant embodied carbon (EC). However, the assessment practice seems cumbersome due to variation in data and methodologies. To this end, this study aims to develop a basis that would facilitate early-stage EC assessment for a proposed building. Design/methodology/approach This study primarily involved a quantitative analysis of 50 Bill of Quantities (BOQs) of two-story house projects. Additional information such as materials, vehicle and plant and equipment used in construction was obtained from technical specifications, industry practiced norms and databases. The EC emission was calculated using basic statistics. Findings The total EC emission in the construction of a two-storey residential building is equivalent to 0.0607 tCO2e per square feet of Gross Internal Floor Area (GIFA). Concrete is the highest contributor in the material production with 36% of emission in the production stage that is responsible for 94% of total EC. The excavation and earthwork is the highest EC emitter during the material transportation stage (93% of total EC emission in transportation stage). During the construction stage, reinforcement shows the highest emission of 85% of total EC emission in construction. The study concludes that the distribution of carbon emission among elements contributes efficient resource allocation towards achieving sustainability in buildings. Originality/value This study provides a basis to forecast the EC emitted during cradle-to-end-of-construction stage of a proposed building. From the implication perspective, it is expected that the basis which the study provides would enable to determine the appropriate carbon tax to account the potential client for his contribution to GHGs.

Abstract This study explores the urgent need for an embodied carbon (EC) assessment framework within Qatar's construction sector, driven by the country's rapid development and high carbon intensity in construction materials, such as cement and steel. Employing a systematic literature review through the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology and Visualization of Similarities (VOS) viewer for bibliometric analysis, this study identifies major gaps in Qatar-specific EC data and regulation. It highlights global best practices, particularly those from countries with mandated EC regulations, and discusses their potential adaptation to Qatar's unique environmental and economic context. This study advocates the establishment of a comprehensive EC database to inform construction practices aligned with Qatar's sustainability goals under its National Vision 2030. The findings suggest that a regionally adapted EC framework would significantly aid Qatar in reducing greenhouse gas emissions, given the country's heavy reliance on energy-intensive materials and its extreme climate. The study concludes with recommendations for the policy integration of EC assessments in Qatar's building sector, aiming to support sustainable urban development and climate resilience in the face of intensifying environmental challenges.

The Government of Korea uses green remodeling (GR) as a central policy for achieving carbon neutrality in the building sector. However, despite GR’s energy-saving benefits, it raises embodied carbon (EC) due to the incorporation of new materials, and there is a lack of impact analysis and assessment research. Thus, this study established the GR-LCA methodology to evaluate the environmental impacts (EIs) of GR, including EC. The methodology disaggregated and assessed the effects of EC and energy on GR in terms of GR’s proportion of EC, six EI categories, and the carbon reduction impacts. The analysis revealed that GR’s EC accounted for 10.6%, reducing to 9.89% when EPD materials were used. In terms of the reduction impact across six EIs, GWP was reduced to 0.84 and EP to 0.96. However, ODP, ADP, AP, and POCP, all elevated by high EIs from material inputs, increased to 626.7, 1.04, 1.16, and 250.09, respectively. Ultimately, the carbon reduction in GR was 24.9% when considering only energy usage, and 16.1% when including EC. When EPD materials were applied, the efficiency of reduction improved by an additional 0.6%, indicating a minimal application effect. Based on these findings, the differences in GR’s EC compared to new constructions, reduction limitations, and potential improvements were discussed.

The climate emergency calls for carbon drawdown to be applied at scale to offset the ‘hard to abate’ emission reductions that threaten Net Zero. The use of biogenic materials in construction promises benefits in terms of low embodied carbon (EC), but timber harvested today only sequestered atmospheric carbon (AC) in the past. A reduction in future AC concentration is only possible from today, and harvesting timber harms a forest’s ability to sequester carbon in the future, unless a level of afforestation can be guaranteed. Current Whole Life Carbon (WLC) assessment methodologies confuse the perceived value of past sequestration, making it seem equivalent to EC, or implying a guarantee of future AC. This study seeks to connect these two opposing elements by finding a forest management ‘success’ value (FS) at which harvesting losses are outweighed by future sequestration, and a net benefit (in future AC terms) can be justifiably claimed. The research proposes a measure of forestry success (a standard established in terms of net sequestration per hectare) and cumulatively offsets losses through harvest against additional drawdown achieved in a well-managed forest. The results show that current boreal forest management regimes do not guarantee a net benefit, but that only modest improvements from a contemporary baseline would be required to see a net benefit by 2050. Recommendations are made to establish a carbon-focused standard for forestry management to replace current binary sustainability accreditations.

While the core objective of the Paris Agreement is to limit the increase in global average temperature (GAT) to 2 °C in the 21st century and to work towards limiting it to 1.5 °C, globalization and the configuration of production processes around global value chains (GVCs) have emerged as key factors explaining the recent evolution of environmental and economic indicators. In this context, this paper takes trade-implied carbon emissions as the entry point of the problem, uses MRIO to calculate the production-side and consumption-side carbon emissions, measures the forward and backward production lengths of GVCs according to the WWYZ method, and then constructs an econometric regression model to empirically analyze the environmental effects of GVC embeddedness. The results of the study show that, firstly, the forward and backward production length of GVCs is positively correlated with the production-side and consumption-side carbon emissions. Forward production length has a greater impact on carbon emissions on the production side, and backward production length has a greater impact on carbon emissions on the consumption side. Secondly, compared with developed countries, the length of forward and backward production has a more pronounced positive impact on carbon emissions in developing countries. Thirdly, as the global production chain continues to extend, the scale effect, structural effect, technological effect, and environmental regulation effect will all contribute to carbon emissions. Accordingly, countries or regions should continuously optimize production layout and processes to reduce the length of the production chain, realize lean manufacturing through automation and intelligence, and then move up the global value chain to play a role in carbon emission reduction through structural upgrading, technological progress, and environmental regulation.

Purpose While operational carbon (OC) emission reduction strategies have received substantial attention in past literature, very few studies have focused on embodied carbon (EC) emission reduction in the construction industry. Therefore, this study aims at undertaking a scientometric review of strategies to mitigate EC emissions in the construction industry. Design/methodology/approach Scopus search engine was used to search for articles. VOSViewer software was used for scientometric analysis using science mapping approach. Using a total of 151 documents, keywords, authors, papers and their sources were analysed. Furthermore, scientometric analysis was undertaken comprising co-occurrence of keywords, documents source analysis and author co-citation analysis. Findings The significant strategies identified to mitigate EC emissions were: offsite manufacturing/use of prefabricated elements, decarbonisation of energy grid, enhanced policies and regulations by governments, construction sector policies and regulations, guidelines for increased use of low EC materials and reuse and recovery of EC construction materials. Practical implications This study identifies practical strategies that contribute to reduction of EC emissions. Originality/value This study is significant and contributes to the construction industry’s agenda to mitigate greenhouse gas emissions.

This study compares the minimum requirements of the Turkish Earthquake Codes (TEC 2007 and TEC 2018) and Eurocode 8 (EC8) for reinforced concrete (RC) frames, integrating seismic safety with material efficiency, cost, and environmental sustainability, specifically focusing on embodied energy (EE) and embodied carbon (EC). The analysis encompasses 4-, 7-, and 10-story RC frames with 6m bays and 3.5m story heights. The results indicate that both material usage and construction costs increase proportionally with an increase in building height for each seismic code. EC8 requires more concrete than TEC, while TEC requires more steel than EC8 for all buildings under consideration. Additionally, EC8 presents a more sustainable alternative compared to the Turkish codes. Notably, while EC8 requires up to 14% more concrete, it requires 27% less steel than TEC 2018, leading to a reduction in overall EE (by 9-11%) and EC (by 3-5%) per floor area. The findings highlight trade-offs between enhanced safety provisions and sustainability, providing recommendations for code harmonization that aim to optimize resource utilization in seismically active regions.

Industrial buildings play vital roles in a society, from shaping the economic, technological, cultural, and social fabric of society to contributing to its growth, development, and resilience. Hence, often at the end of their lifespans, they are “preserved” for their historical value through renovation. Considerations for renovation often include their historical significance, structural integrity, adaptive reuse, social sustainability, financial viability, and environmental impacts. Among these considerations, the carbon emissions associated with a project are increasingly becoming a factor of relevance when a historical building is to be sensitively renovated so that it can continue to contribute to local sustainability. However, embodied carbon is often overshadowed by operational carbon and overlooked in the development of renovation options. This paper argues for the need to include embodied carbon in the consideration of any renovation process and for guidelines for doing so. The argument is built upon a systematic review of current practices in the renovation of industrial heritage buildings across selected representative countries from the Global South and the Global North, in the belief that the former could learn valuable lessons from the latter, which has more extensive experience in considering embodied carbon in such processes. The argument also shows the difference in policy between different countries and articulates how the inclusion of embodied carbon might support environmental targets in the Global South. Based on a quantitative comparison, this review explains why embodied carbon (EC) is missing in renovations of industrial heritage buildings in the Global South. This study estimates the proportion and value of EC within the total life cycle in renovations of industrial buildings to support the argument. Above all, a calculation using a standard life cycle assessment (LCA) tool (ISO14040 & 14044) applied to four successful examples and a quantitative comparison highlight the benefits of including embodied carbon in renovations of industrial buildings and the carbon savings in the Global South and further supports our argument.