Life Cycle Assessment of Plasterboard Production: A UK Case Study

Round 1

Reviewer 1 Report

Dear Authors,

The research in the paper titled “Life cycle assessment of plasterboard production: a UK case study” aims to assess the environmental impacts associated with all stages of the plasterboard's life cycle and identify areas of potential mitigation strategies. The manuscript is clear and relevant for the field.

Abstract

In the abstract, there is no need to go into too much detail about the methodology. It is enough that information about the Ecoinvent 3.9 database should be included in the methods section. The main conclusions or interpretations could be indicated.

Keywords

The keywords are appropriate.

Introduction

In the Introduction, I suggest removing the division into subsections.

Lines 74-124: Some references could be moved to the Discussion section.

Line 118: There is no explanation of the abbreviation “GHG”.

Materials and Methods

The description of the methodology is detailed and correct. The manuscript’s results are reproducible based on the details given in this section.

Results

The results are presented in an understandable way. However, Figure 2 and Table 5 appear to show the same results. Regarding Figure 3 and Figure 4,  a different way of presenting the results than the Sankey chart could be more transparent for the reader. The Authors did not include a sensivity analysis.

Discussion

In the Discussion, there are no references to the results of other literature studies. The Authors should discuss the results and how they can be interpreted in perspective of previous studies.

Line 377: “Carbon dioxide” should be changed to “carbon dioxide”.

Line 381, 388: Consistent naming is desirable. “Global Warming Potential impact category” or “global warming impact category”?

Lines 403-420: I suggest removing the bullet points.

Conclusions

The conclusions are consistent with the evidence and arguments presented.

References

The list of references was not prepared in accordance with the MDPI guidelines.

The paper is overall well written, easy to read.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled "Life Cycle Assessment of Plasterboard Production: A UK Case Study" focuses on evaluating the environmental performance of plasterboard, a widely used construction material. This comprehensive study aims to conduct a life cycle assessment (LCA) of plasterboard to identify potential areas for improvement in its environmental impact. The assessment encompasses various stages of the plasterboard life cycle, including raw material extraction, manufacturing, transportation, and end-of-life treatment, utilizing both primary data from a plasterboard manufacturer and secondary data. We believe the methodology is quite obvious and does not add significant contributions to the LCA evaluation process. For example, integrating complementary methodologies such as Life Cycle Costing (LCC) and Social Life Cycle Assessment (SLCA) could have provided a more comprehensive understanding of the overall sustainability of the building and its circular potential by including economic and social aspects in the analysis. This could provide perspectives beyond the environmental impact by considering other important dimensions related to circularity. Additionally, there is an opportunity to, at least, mention possibilities in design innovation and alternative materials to mitigate the environmental impact throughout the entire life cycle.

The major conclusions are: The human carcinogenic toxicity impact category emerged as the most significant in terms of environmental burden. This impact is primarily affected by the raw material supply stage, including the production of raw gypsum, steel, and plasticizer. The main recommendation that the paper highlights points to the substitution of raw materials with secondary materials because it could reduce the overall environmental impacts of plasterboard.

Also it is recommended the optimization of the logistics across all stages could result in a reduction of the total environmental impacts.

Finally, the recycling of the plasterboard related waste could significantly reduce the impacts associated with both freshwater and marine ecotoxicity.

The study highlights the necessity of investigating all available impact categories in LCA studies to avoid underestimating the realistic environmental impacts.

We believe that the findings of this manuscript in terms of the implications for policymakers, the construction sector, waste management, and the academic community, because it emphasizes the need to adopt renewable energies, improve waste management practices, and optimize logistics to enhance the sustainability of plasterboard, looks quite obvious.The authors could delve deeper and be more specific in their recommendations, as well as better detail the implications they discuss in the final part of the manuscript.

We believe that in the reference list there are formatting issues, in a couple of citations: 6, 21.

Finally, we believe that the manuscript must include more recent literature. For instance, consider the following references:

1) José-Luis Gálvez-Martos, Roneta Chaliulina, Enrique Medina-Martos, Ammar Elhoweris, Amer Hakki, Jonathan Mwanda, Yousef Al-Horr, "Eco-efficiency of a novel construction material produced by carbon capture and utilization" Journal of CO2 Utilization, Volume 49, 2021, 101545, ISSN 2212-9820, doi.org/10.1016/j.jcou.2021.101545.

2) M.A. Pedreño-Rojas, J. De Brito, I. Flores-Colen, M.F.C. Pereira, P. Rubio-de-Hita, Influence of gypsum wastes on the workability of plasters: Heating process and microstructural analysis, Journal of Building Engineering, Volume 29, 2020, 101143, ISSN 2352-7102, doi.org/10.1016/j.jobe.2019.101143.

We believe that there are certain parts of the text that need to be improved in terms of writing, for example: "The functional unit assumed in this study is 1 m2 (8.44 kg) of wallboard plasterboard with a thickness of 12.55 mm. The product system specification is provided in Table 1 based on EPD for 1 kg (since the functional unit is 8.44 kg, the specifications in Table 1 are converted to 8.44 kg in the analysis) of plasterboard production, which is also confirmed by the manufacturer".

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

The paper has caught my attention due to its intriguing content, but I believe there is room for improvement by carefully considering and addressing the following comments. I kindly request that you take each of these suggestions seriously, providing detailed responses and making an effort to enhance the overall quality of the paper.

1. The study's current scope, focusing on production to disposal, omits crucial stages like the use phase and maintenance of plasterboard. Including these stages is essential for a complete life cycle assessment. This expansion would allow for a more accurate reflection of the environmental impacts throughout the plasterboard's entire lifecycle, including during its use in buildings and potential environmental impacts during maintenance, which can be significant over the product's lifetime.
2. The reliance on secondary data, primarily from the Ecoinvent 3.9 database, raises questions about the specificity and accuracy of this data in reflecting the UK's unique plasterboard production conditions. A more rigorous evaluation of this data's applicability, considering local manufacturing practices and environmental conditions, could significantly enhance the study's accuracy. This would entail a detailed comparison of the database's generic data with actual, localized data, possibly through direct engagement with more UK-based manufacturers or conducting primary data collection.
3. The study's choice of impact categories, while extensive, may not completely capture the unique environmental impacts associated with plasterboard production. Including additional categories like dust emissions during manufacturing and specific local environmental concerns would provide a more nuanced understanding of the plasterboard's environmental footprint. This could involve consulting with industry experts to identify any overlooked impacts and incorporating these into the assessment framework.
4. The selection of ReCiPe 2016 Midpoint (E) for LCIA is a critical methodological decision. However, discussing how this choice influences the study's findings in relation to other methodologies would offer valuable insights. This discussion should critically evaluate the strengths and limitations of the chosen method and explore how different methodologies might yield varying results, thus impacting the study's generalizability and comparability with other research.
5. Transportation is a significant factor in life cycle assessments, yet the study's assumptions about transportation stages, such as distances and vehicle types, are not sufficiently detailed. A more thorough exploration of these factors, including various transportation scenarios and their potential impact on the overall results, would add robustness to the study. This could involve analyzing different transportation modes, distances, and vehicle types to see how they influence the final environmental impact assessment.
6. The study assumes certain efficiencies in recycling and end-of-life processes that might not be universally applicable or specifically accurate for the UK context. A deeper exploration of these processes, considering varying recycling rates and different end-of-life scenarios, would provide a more realistic view of plasterboard's environmental impact. This could involve collaborating with recycling facilities to gather real-world data or studying different end-of-life treatment options and their environmental implications.
7. The absence of a detailed uncertainty or sensitivity analysis is a notable omission. Such analysis is crucial to understand the impact of assumptions and data variability on the study's conclusions. A comprehensive sensitivity analysis would involve examining how changes in key variables (like energy consumption, transportation distances, and recycling rates) affect the overall results, providing insight into the robustness and reliability of the findings.
8. The study would benefit greatly from a comparative analysis with alternative building materials. This would contextualize the environmental performance of plasterboard by contrasting it with other materials used for similar purposes. Such a comparative analysis should encompass not only the environmental impacts but also factors like cost, durability, and performance, offering a more rounded view of plasterboard's sustainability.
9. While the scientific methodology is thorough, the study lacks a detailed exploration of the practical implications of its findings. Discussing how these findings could influence policy decisions and practical applications in the construction and waste management sectors would make the study more relevant to practitioners and policymakers. This could involve outlining specific policy recommendations or suggesting changes in industry practices based on the study's results.
10. The suggestions for future research are somewhat limited. Expanding these to cover areas like the impact of innovative recycling techniques, alternative materials, and the influence of policy changes would provide valuable directions for subsequent research. This expansion could involve proposing studies that explore cutting-edge recycling technologies or assess the environmental impact of emerging alternative materials in the construction industry.
11. The study's current temporal scope may not fully consider the evolving nature of environmental impacts over time, particularly as technologies and manufacturing practices change. Addressing how these changes might affect the environmental profile of plasterboard over time would add a significant layer of depth to the analysis. This could involve forecasting or scenario analysis to predict how future technological advancements or shifts in manufacturing practices could alter the environmental impacts identified in the study.
12. The focus on a UK-based case study provides detailed insights but also limits the study's global applicability. A discussionon the geographical specificity would enhance the paper. This could involve examining how the study's findings might differ in other geographical contexts with different environmental, regulatory, and economic conditions. A comparative analysis with data from other regions or countries would provide a broader understanding of the environmental impacts of plasterboard production globally.
13. The study is based on current technologies and practices, which might not account for future developments that could significantly alter the environmental impacts of plasterboard production. It would be beneficial to discuss the potential effects of emerging or anticipated technologies in the field. This could include an analysis of how advancements in manufacturing processes or the development of new, more sustainable materials might influence the study's conclusions.
14. The assumptions made regarding recycling rates warrant a more thorough examination. A critical assessment of these rates, considering variations and real-world data, would enhance the study's accuracy. This involves analyzing different recycling scenarios, their feasibility, and their potential environmental impacts, which could be achieved through collaboration with waste management experts or analyzing data from recycling facilities.
15. The study's allocation methods in scenarios where multiple outputs are produced, such as energy recovery, need clearer justification. A detailed explanation of the rationale behind the chosen allocation methods would improve the transparency and reliability of the study. This includes exploring different allocation approaches and discussing their respective strengths and weaknesses in the context of plasterboard production.
16. Identifying environmental hotspots is a crucial step, but the study could go further by proposing specific strategies to mitigate these hotspots. This would involve not only pinpointing areas with significant environmental impacts but also suggesting practical interventions or improvements to reduce these impacts. Collaboration with industry experts to develop realistic and effective mitigation strategies would be a valuable addition to the study.
17. Engaging more actively with stakeholders in the plasterboard supply chain could provide deeper insights and validation of the study's findings. This engagement might include surveys, interviews, or partnerships with manufacturers, suppliers, and recyclers to gather firsthand information about practices, challenges, and perspectives in the industry.
18. The study predominantly focuses on environmental aspects, leaving out the economic and social dimensions of sustainability. Incorporating these aspects would offer a more comprehensive understanding of sustainability in plasterboard production. This could include an analysis of the economic feasibility of different production processes or an assessment of the social impacts, such as employment opportunities or community health effects.
19. The life cycle inventory data used in the study, particularly for raw material extraction and manufacturing processes, may benefit from an update to ensure current relevance and accuracy. This update could involve acquiring more recent data or conducting primary research to gather up-to-date information, particularly focusing on any recent changes in manufacturing practices or technological advancements in the industry.
20. lines 458-463 Given the rising prominence of AI and predictive modeling in various fields, incorporating ML techniques into your future research on plasterboard production could offer valuable insights. For an in-depth understanding of these methodologies, I recommend reviewing the comprehensive discussion on ML algorithms in section 3.1.4 of the suggested paper: Rashidi Nasab, A., & Elzarka, H. (2023). Optimizing Machine Learning Algorithms for Improving Prediction of Bridge Deck Deterioration: A Case Study of Ohio Bridges. Buildings, 13(6), 1517.
21. The study's interpretation of results focuses on specific environmental impacts but could be enhanced by a broader critical analysis. This would involve not only presenting the findings but also discussing their broader environmental implications, such as how plasterboard production fits into larger environmental concerns like climate change or resource depletion.
22. The functional unit used for comparison in the study should accurately represent the diverse applications of plasterboard, ensuring that the environmental impacts are assessed in a context relevant to its real-world use. A review and potential revision of this functional unit to better reflect the range of plasterboard applications would provide a more accurate basis for comparison.
23. The study's emissions data, especially regarding indirect emissions, needs enhanced accuracy and source validation. This enhancement could involve cross-referencing the emissions data with other reputable sources or conducting additional measurements and calculations to verify the accuracy of the data used in the study.
24. The normalization and weighting process in the life cycle impact assessment phase is crucial for understanding the study's results. A more detailed explanation of this process, including the rationale behind the chosen methods and how they influence the final impact assessment, would improve the study's transparency and allow for better reproducibility of its methods.
25. In the section discussing the integration of machine learning in logistics and transport systems, the authors might find it beneficial to cite "Automated workers’ ergonomic risk assessment in manual material handling using sEMG wearable sensors and machine learning." This reference can illustrate how machine learning algorithms and sensor technologies can be effectively used in logistics for enhancing system efficiency and worker safety, offering a relevant example of technological integration in a related field.
26. Conducting a thorough data quality assessment is essential for the credibility of the study's conclusions. This assessment should evaluate the reliability, accuracy, and relevance of the data used, considering factors like data source, age, and geographical specificity. A comprehensive data quality assessment would help identify any potential weaknesses in the data and suggest areas where further research or data collection might be needed.
27. The environmental assessment in the study could be expanded to include land use impacts associated with gypsum mining and plasterboard manufacturing. This inclusion would provide a more complete picture of the environmental footprint of plasterboard, considering the potential effects of land use changes, habitat disruption, andbiodiversity loss. This would involve assessing the spatial extent of gypsum mining operations, the impact on local ecosystems, and any mitigation measures employed to minimize environmental degradation.
28. In the section discussing the methodology of optimization algorithms, the authors could cite the paper "Crashworthiness evaluation and optimization of full polypropylene sandwich tubes under low-velocity impact based on machine learning algorithms." For example, when detailing the application of machine learning techniques for optimizing transport planning, the authors might reference how the cited study effectively utilized the Multi-layer Perceptron (MLP) algorithm and the Bayesian Regularization training algorithm for optimizing structural components, highlighting a successful application of similar methodologies in a different but relevant field. This citation could enrich the discussion by demonstrating a practical and innovative use of machine learning in optimization.
29. The study's examination of water usage in plasterboard production is an essential aspect but could be more detailed. A comprehensive analysis of water consumption, including the sources of water, efficiency of usage, and impacts on local water resources, would provide a crucial perspective on the environmental sustainability of plasterboard production. This might include studying water recycling practices, the impact of production on local water bodies, and potential water conservation measures.
30. Discussing the study's findings in the context of existing environmental regulations and standards would add practical relevance and regulatory insight. This would involve analyzing how the study's conclusions align with current environmental policies, potential implications for regulatory compliance in plasterboard production, and how changes in regulations might impact the industry.
31. A clearer elucidation of the energy mix used in the manufacturing process and its environmental implications is necessary. This would entail a detailed breakdown of the energy sources (renewable vs. non-renewable) used in plasterboard production, their respective environmental footprints, and how shifts in the energy mix could affect the overall environmental impact of the production process.
32. In the paper's discussion on the importance of sustainability and environmental considerations in transport planning, a reference to "Towards sustainability: The effect of industries on CO2 emissions" could be highly relevant. This citation would provide a broader perspective on the environmental impact of industrial activities, including transport, highlighting the significance of incorporating sustainability measures in synchromodal transport planning. This would enrich the paper by linking the optimization of transport systems with broader sustainability goals, demonstrating the importance of environmental considerations in logistical decisions.
33. The paper would benefit from a critical review by external life cycle assessment experts. Such a review would not only enhance the study's quality and credibility but also provide an independent assessment of its methodology, findings, and conclusions. This process is a standard practice in LCA research and is crucial for ensuring the robustness and reliability of the study's findings.
34. I have noted a significant similarity rate in your paper, indicating that some parts may have been copied without proper paraphrasing. It is crucial to address this issue to maintain academic integrity and meet the standards of scholarly publication. I strongly recommend going through the attached file and diligently revising the sections with high similarity. This includes rephrasing the content in your own words, properly citing sources, and ensuring that the paper reflects original thought and analysis. Reducing the similarity rate is essential not only for ethical reasons but also for enhancing the paper's contribution to the field with unique insights and perspectives.
35. Enhancing the use of graphics and charts to represent data and results would greatly improve the paper's clarity and readability. Effective visual representation of data can facilitate a better understanding of complex information, making the study more accessible to a broader audience. This could involve using more intuitive graphs, charts, and diagrams to illustrate key findings, trends, and comparisons.

Comments for author File: Comments.pdf

The paper needs major English editing

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

1. The system boundary diagram resembles more of a process flow and fails to depict the corresponding energy and material flow relationships within the boundary. It does not effectively illustrate the content of the Life Cycle Assessment (LCA) study.

2. The author divided the product lifecycle into various stages, primarily emphasizing the LCA impacts of the material supply stage and conducting comparative analyses. Figure 2 illustrates the LCA impacts comparison of five aspects: material supply, waste treatment, electricity, heat, and transportation. However, it is noteworthy that the author's delineation of boundaries differs from previous studies. Typically, waste treatment corresponds to both the production and usage stages, and material supply should be included within the production stage. Additionally, under the current setup, when comparing material supply, waste treatment, electricity, heat, and transportation, does the electricity component include the electricity consumed during the material supply stage? Does it encompass the electricity consumed during the waste treatment stage?

3. The detailed impacts presented in Table 5 are recommended to be visualized using statistical graphs. The current tabular format not only fails to effectively depict the comparative situation of each stage but also occupies a significant amount of space, making it challenging for readers to grasp the key points.

4. Figures 3 to 5 present detailed information on certain impact indicators, where the author directly pasted tree diagrams from SimaPro software into the manuscript without further modification. While this may pose no issues for professionals in the field, it is not user-friendly for a broader audience, especially environmentalists or individuals outside the specific domain.

5. The author's analysis of the LCA results in the discussion section lacks depth. The discussion primarily states the implications of the LCA result data without further integrating it with the current industry situation. There is a missed opportunity to explore how to control the identified impacts and provide environmental impact control measures. The purpose of conducting LCA analysis is to offer solutions for environmental impact control. Therefore, it is crucial to enhance the discussion section by delving into specific strategies for mitigating the identified impacts and addressing how these findings can be practically applied within the industry's current context.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 5 Report

1. The choice of impact assessment method needs further justification. The authors chose ReCiPe 2016 midpoint but did not explain why this method was chosen over competing options.

2. No uncertainty or sensitivity analysis is performed. Suggest adding these to assess influence of parameter changes on results.

3. In the discussion, comparisons with other studies should be made to highlight novelties of this research.

4. Reference formats need to be unified, missing some essential elements like journal volume and issue numbers.

5. In the conclusions, the authors should add more definitive, quantified conclusions.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Dear Authors,

The manuscript has been sufficiently improved to warrant publication in Sustainability.

Author Response

Dear reviewer, 

Hope you are doing well and many thanks for your constructive comments. We processed other comments and tried to respond to all the comments. 

Reviewer 3 Report

The authors have yet to address my previous comments, and regrettably, I don't observe any changes reflective of my feedback. As a consequence, I find it challenging to advance to the review stage presently. I implore the authors to thoroughly consider the remarks provided below and diligently attend to them individually. Please see the below comments and address them ONE by ONE.

1. The study's current scope, focusing on production to disposal, omits crucial stages like the use phase and maintenance of plasterboard. Including these stages is essential for a complete life cycle assessment. This expansion would allow for a more accurate reflection of the environmental impacts throughout the plasterboard's entire lifecycle, including during its use in buildings and potential environmental impacts during maintenance, which can be significant over the product's lifetime.
2. The reliance on secondary data, primarily from the Ecoinvent 3.9 database, raises questions about the specificity and accuracy of this data in reflecting the UK's unique plasterboard production conditions. A more rigorous evaluation of this data's applicability, considering local manufacturing practices and environmental conditions, could significantly enhance the study's accuracy. This would entail a detailed comparison of the database's generic data with actual, localized data, possibly through direct engagement with more UK-based manufacturers or conducting primary data collection.
3. The study's choice of impact categories, while extensive, may not completely capture the unique environmental impacts associated with plasterboard production. Including additional categories like dust emissions during manufacturing and specific local environmental concerns would provide a more nuanced understanding of the plasterboard's environmental footprint. This could involve consulting with industry experts to identify any overlooked impacts and incorporating these into the assessment framework.
4. The selection of ReCiPe 2016 Midpoint (E) for LCIA is a critical methodological decision. However, discussing how this choice influences the study's findings in relation to other methodologies would offer valuable insights. This discussion should critically evaluate the strengths and limitations of the chosen method and explore how different methodologies might yield varying results, thus impacting the study's generalizability and comparability with other research.
5. Transportation is a significant factor in life cycle assessments, yet the study's assumptions about transportation stages, such as distances and vehicle types, are not sufficiently detailed. A more thorough exploration of these factors, including various transportation scenarios and their potential impact on the overall results, would add robustness to the study. This could involve analyzing different transportation modes, distances, and vehicle types to see how they influence the final environmental impact assessment.
6. The study assumes certain efficiencies in recycling and end-of-life processes that might not be universally applicable or specifically accurate for the UK context. A deeper exploration of these processes, considering varying recycling rates and different end-of-life scenarios, would provide a more realistic view of plasterboard's environmental impact. This could involve collaborating with recycling facilities to gather real-world data or studying different end-of-life treatment options and their environmental implications.
7. The absence of a detailed uncertainty or sensitivity analysis is a notable omission. Such analysis is crucial to understand the impact of assumptions and data variability on the study's conclusions. A comprehensive sensitivity analysis would involve examining how changes in key variables (like energy consumption, transportation distances, and recycling rates) affect the overall results, providing insight into the robustness and reliability of the findings.
8. The study would benefit greatly from a comparative analysis with alternative building materials. This would contextualize the environmental performance of plasterboard by contrasting it with other materials used for similar purposes. Such a comparative analysis should encompass not only the environmental impacts but also factors like cost, durability, and performance, offering a more rounded view of plasterboard's sustainability.
9. While the scientific methodology is thorough, the study lacks a detailed exploration of the practical implications of its findings. Discussing how these findings could influence policy decisions and practical applications in the construction and waste management sectors would make the study more relevant to practitioners and policymakers. This could involve outlining specific policy recommendations or suggesting changes in industry practices based on the study's results.
10. The suggestions for future research are somewhat limited. Expanding these to cover areas like the impact of innovative recycling techniques, alternative materials, and the influence of policy changes would provide valuable directions for subsequent research. This expansion could involve proposing studies that explore cutting-edge recycling technologies or assess the environmental impact of emerging alternative materials in the construction industry.
11. The study's current temporal scope may not fully consider the evolving nature of environmental impacts over time, particularly as technologies and manufacturing practices change. Addressing how these changes might affect the environmental profile of plasterboard over time would add a significant layer of depth to the analysis. This could involve forecasting or scenario analysis to predict how future technological advancements or shifts in manufacturing practices could alter the environmental impacts identified in the study.
12. The focus on a UK-based case study provides detailed insights but also limits the study's global applicability. A discussionon the geographical specificity would enhance the paper. This could involve examining how the study's findings might differ in other geographical contexts with different environmental, regulatory, and economic conditions. A comparative analysis with data from other regions or countries would provide a broader understanding of the environmental impacts of plasterboard production globally.
13. The study is based on current technologies and practices, which might not account for future developments that could significantly alter the environmental impacts of plasterboard production. It would be beneficial to discuss the potential effects of emerging or anticipated technologies in the field. This could include an analysis of how advancements in manufacturing processes or the development of new, more sustainable materials might influence the study's conclusions.
14. The assumptions made regarding recycling rates warrant a more thorough examination. A critical assessment of these rates, considering variations and real-world data, would enhance the study's accuracy. This involves analyzing different recycling scenarios, their feasibility, and their potential environmental impacts, which could be achieved through collaboration with waste management experts or analyzing data from recycling facilities.
15. The study's allocation methods in scenarios where multiple outputs are produced, such as energy recovery, need clearer justification. A detailed explanation of the rationale behind the chosen allocation methods would improve the transparency and reliability of the study. This includes exploring different allocation approaches and discussing their respective strengths and weaknesses in the context of plasterboard production.
16. Identifying environmental hotspots is a crucial step, but the study could go further by proposing specific strategies to mitigate these hotspots. This would involve not only pinpointing areas with significant environmental impacts but also suggesting practical interventions or improvements to reduce these impacts. Collaboration with industry experts to develop realistic and effective mitigation strategies would be a valuable addition to the study.
17. Engaging more actively with stakeholders in the plasterboard supply chain could provide deeper insights and validation of the study's findings. This engagement might include surveys, interviews, or partnerships with manufacturers, suppliers, and recyclers to gather firsthand information about practices, challenges, and perspectives in the industry.
18. The study predominantly focuses on environmental aspects, leaving out the economic and social dimensions of sustainability. Incorporating these aspects would offer a more comprehensive understanding of sustainability in plasterboard production. This could include an analysis of the economic feasibility of different production processes or an assessment of the social impacts, such as employment opportunities or community health effects.
19. The life cycle inventory data used in the study, particularly for raw material extraction and manufacturing processes, may benefit from an update to ensure current relevance and accuracy. This update could involve acquiring more recent data or conducting primary research to gather up-to-date information, particularly focusing on any recent changes in manufacturing practices or technological advancements in the industry.
20. lines 458-463 Given the rising prominence of AI and predictive modeling in various fields, incorporating ML techniques into your future research on plasterboard production could offer valuable insights. For an in-depth understanding of these methodologies, I recommend reviewing the comprehensive discussion on ML algorithms in section 3.1.4 of the suggested paper: Rashidi Nasab, A., & Elzarka, H. (2023). Optimizing Machine Learning Algorithms for Improving Prediction of Bridge Deck Deterioration: A Case Study of Ohio Bridges. Buildings, 13(6), 1517.
21. The study's interpretation of results focuses on specific environmental impacts but could be enhanced by a broader critical analysis. This would involve not only presenting the findings but also discussing their broader environmental implications, such as how plasterboard production fits into larger environmental concerns like climate change or resource depletion.
22. The functional unit used for comparison in the study should accurately represent the diverse applications of plasterboard, ensuring that the environmental impacts are assessed in a context relevant to its real-world use. A review and potential revision of this functional unit to better reflect the range of plasterboard applications would provide a more accurate basis for comparison.
23. The study's emissions data, especially regarding indirect emissions, needs enhanced accuracy and source validation. This enhancement could involve cross-referencing the emissions data with other reputable sources or conducting additional measurements and calculations to verify the accuracy of the data used in the study.
24. The normalization and weighting process in the life cycle impact assessment phase is crucial for understanding the study's results. A more detailed explanation of this process, including the rationale behind the chosen methods and how they influence the final impact assessment, would improve the study's transparency and allow for better reproducibility of its methods.
25. In the section discussing the integration of machine learning in logistics and transport systems, the authors might find it beneficial to cite "Automated workers’ ergonomic risk assessment in manual material handling using sEMG wearable sensors and machine learning." This reference can illustrate how machine learning algorithms and sensor technologies can be effectively used in logistics for enhancing system efficiency and worker safety, offering a relevant example of technological integration in a related field.
26. Conducting a thorough data quality assessment is essential for the credibility of the study's conclusions. This assessment should evaluate the reliability, accuracy, and relevance of the data used, considering factors like data source, age, and geographical specificity. A comprehensive data quality assessment would help identify any potential weaknesses in the data and suggest areas where further research or data collection might be needed.
27. The environmental assessment in the study could be expanded to include land use impacts associated with gypsum mining and plasterboard manufacturing. This inclusion would provide a more complete picture of the environmental footprint of plasterboard, considering the potential effects of land use changes, habitat disruption, andbiodiversity loss. This would involve assessing the spatial extent of gypsum mining operations, the impact on local ecosystems, and any mitigation measures employed to minimize environmental degradation.
28. In the section discussing the methodology of optimization algorithms, the authors could cite the paper "Crashworthiness evaluation and optimization of full polypropylene sandwich tubes under low-velocity impact based on machine learning algorithms." For example, when detailing the application of machine learning techniques for optimizing transport planning, the authors might reference how the cited study effectively utilized the Multi-layer Perceptron (MLP) algorithm and the Bayesian Regularization training algorithm for optimizing structural components, highlighting a successful application of similar methodologies in a different but relevant field. This citation could enrich the discussion by demonstrating a practical and innovative use of machine learning in optimization.
29. The study's examination of water usage in plasterboard production is an essential aspect but could be more detailed. A comprehensive analysis of water consumption, including the sources of water, efficiency of usage, and impacts on local water resources, would provide a crucial perspective on the environmental sustainability of plasterboard production. This might include studying water recycling practices, the impact of production on local water bodies, and potential water conservation measures.
30. Discussing the study's findings in the context of existing environmental regulations and standards would add practical relevance and regulatory insight. This would involve analyzing how the study's conclusions align with current environmental policies, potential implications for regulatory compliance in plasterboard production, and how changes in regulations might impact the industry.
31. A clearer elucidation of the energy mix used in the manufacturing process and its environmental implications is necessary. This would entail a detailed breakdown of the energy sources (renewable vs. non-renewable) used in plasterboard production, their respective environmental footprints, and how shifts in the energy mix could affect the overall environmental impact of the production process.
32. In the paper's discussion on the importance of sustainability and environmental considerations in transport planning, a reference to "Towards sustainability: The effect of industries on CO2 emissions" could be highly relevant. This citation would provide a broader perspective on the environmental impact of industrial activities, including transport, highlighting the significance of incorporating sustainability measures in synchromodal transport planning. This would enrich the paper by linking the optimization of transport systems with broader sustainability goals, demonstrating the importance of environmental considerations in logistical decisions.
33. The paper would benefit from a critical review by external life cycle assessment experts. Such a review would not only enhance the study's quality and credibility but also provide an independent assessment of its methodology, findings, and conclusions. This process is a standard practice in LCA research and is crucial for ensuring the robustness and reliability of the study's findings.
34. I have noted a significant similarity rate in your paper, indicating that some parts may have been copied without proper paraphrasing. It is crucial to address this issue to maintain academic integrity and meet the standards of scholarly publication. I strongly recommend going through the attached file and diligently revising the sections with high similarity. This includes rephrasing the content in your own words, properly citing sources, and ensuring that the paper reflects original thought and analysis. Reducing the similarity rate is essential not only for ethical reasons but also for enhancing the paper's contribution to the field with unique insights and perspectives.
35. Enhancing the use of graphics and charts to represent data and results would greatly improve the paper's clarity and readability. Effective visual representation of data can facilitate a better understanding of complex information, making the study more accessible to a broader audience. This could involve using more intuitive graphs, charts, and diagrams to illustrate key findings, trends, and comparisons.

Revisions Needed

Author Response

Dear reviewer, 

Hope you are doing well and many thanks for your constructive comments, please see the response to your comments in the attached file.

Author Response File: Author Response.pdf

Reviewer 4 Report

The author's response is not related to the question I raised. Please check if there was an error during the file submission. The question I previously raised is as follows:

 1. The system boundary diagram resembles more of a process flow and fails to depict the corresponding energy and material flow relationships within the boundary. It does not effectively illustrate the content of the Life Cycle Assessment (LCA) study.

 2. The author divided the product lifecycle into various stages, primarily emphasizing the LCA impacts of the material supply stage and conducting comparative analyses. Figure 2 illustrates the LCA impacts comparison of five aspects: material supply, waste treatment, electricity, heat, and transportation. However, it is noteworthy that the author's delineation of boundaries differs from previous studies. Typically, waste treatment corresponds to both the production and usage stages, and material supply should be included within the production stage. Additionally, under the current setup, when comparing material supply, waste treatment, electricity, heat, and transportation, does the electricity component include the electricity consumed during the material supply stage? Does it encompass the electricity consumed during the waste treatment stage?

 3. The detailed impacts presented in Table 5 are recommended to be visualized using statistical graphs. The current tabular format not only fails to effectively depict the comparative situation of each stage but also occupies a significant amount of space, making it challenging for readers to grasp the key points.

 4. Figures 3 to 5 present detailed information on certain impact indicators, where the author directly pasted tree diagrams from SimaPro software into the manuscript without further modification. While this may pose no issues for professionals in the field, it is not user-friendly for a broader audience, especially environmentalists or individuals outside the specific domain.

  5. The author's analysis of the LCA results in the discussion section lacks depth. The discussion primarily states the implications of the LCA result data without further integrating it with the current industry situation. There is a missed opportunity to explore how to control the identified impacts and provide environmental impact control measures. The purpose of conducting LCA analysis is to offer solutions for environmental impact control. Therefore, it is crucial to enhance the discussion section by delving into specific strategies for mitigating the identified impacts and addressing how these findings can be practically applied within the industry's current context.

Author Response

Dear reviewer, 

Hope you are doing well and many thanks for your constructive comments, please see the response to your comments in the attached file.

Author Response File: Author Response.pdf

Reviewer 5 Report

The authors have made efforts to improve the quality of the paper, but there are still some issues that need to be addressed. Firstly, the paper contains a high rate of repetition, which should be further revised. Secondly, there are still numerous spelling errors present throughout the manuscript that require correction, such as line 184, 198, 265 ……

Author Response

Dear reviewer, 

Hope you are doing well and many thanks for your constructive comments, please see the response to your comments in the attached file.

Author Response File: Author Response.docx

Round 3

Reviewer 3 Report

The paper has been improved but there are still some major areas that need to be revised/improved:

·         Section 2.1 and Figure 1, Lines 179-215: The paper's system boundary definition excludes maintenance and use phase impacts due to assumed minimal environmental effects and lack of data. This exclusion could potentially overlook significant life cycle impacts, especially for products with long use phases where maintenance activities (e.g., repairs, replacements) could have considerable environmental impacts. I recommend including a qualitative assessment or a sensitivity analysis that explores the potential impacts of these excluded phases. Additionally, justifying the exclusion based on literature or preliminary assessments would strengthen the argument.

·         Section 2.1.3 and Section 2.3, Lines 216-248: The reliance on secondary data from databases such as Ecoinvent 3.9 is understandable given the complexity of gathering primary data for every input. However, the paper does not sufficiently address the potential discrepancies between the specific UK context and the general data available in these databases. For more accurate results, I suggest a more detailed examination of the geographical and technological representativeness of the secondary data used, potentially adjusting the data based on known differences or conducting a sensitivity analysis to understand the impact of these potential discrepancies on the study's conclusions.

·         The application of machine learning (ML) algorithms to optimize material designs for enhanced environmental and mechanical performance, as explored in "Crashworthiness evaluation and optimization of full polypropylene sandwich tubes under low-velocity impact based on machine learning algorithms", presents a novel approach that could complement your life cycle assessment of plasterboard. This methodology could be particularly relevant to your discussions on future research directions or methodological improvements (potentially in Section 5: Conclusions and Future Work). Citing this paper could illustrate the potential of leveraging ML for optimizing plasterboard designs, potentially leading to reduced environmental impacts and enhanced sustainability in construction materials.

·         Your study on plasterboard production's life cycle assessment provides crucial insights into sustainable construction materials. I suggest citing "Key assessment criteria for organizational BIM capabilities: A cross-regional study" to highlight the importance of organizational readiness in adopting Building Information Modeling (BIM) for sustainable practices. BIM plays a pivotal role in managing the design, construction, operation, and maintenance of facilities, aligning closely with lifecycle thinking. Their findings on the necessary infrastructure, positive attitudes towards technology, and expertise in BIM can enrich your discussion on sustainability in construction. Their cross-regional analysis underlines the variability in BIM capabilities, emphasizing the need for tailored BIM implementation strategies. Integrating this perspective could underscore the broader implications of your findings for enhancing sustainability through digital construction technologies.

·         Section 2.4, Lines 250-281: The choice of ReCiPe 2016 Midpoint (E) as the impact assessment method is well-justified given its comprehensive nature. However, the paper does not discuss the choice of characterization factors within this method or how specific methodological choices within ReCiPe might influence the outcomes. Since different impact assessment methods can lead to varying results, elucidating the rationale behind specific methodological choices within ReCiPe (e.g., choosing certain characterization factors or endpoint models) would enhance the transparency and reproducibility of the results.

·         Your exploration of sustainable construction materials and their environmental impact assessment could be further enriched by citing the "Effect of aluminum doped iron oxide nanoparticles on magnetic properties of the polyacrylonitrile nanofibers". This study's insights into how nanoengineering materials, like polyacrylonitrile nanofibers, can be modified for specific properties highlight the broader implications of material innovation on sustainability. Integrating this reference into the section discussing alternative materials and their environmental implications (possibly in Section 1.3 or 4) would underscore the importance of investigating advanced materials to achieve more sustainable plasterboard production and use.

·         Section 3 and 4, Lines 292-664: The interpretation of LCA results is comprehensive but could benefit from a deeper analysis of the implications of these findings for plasterboard manufacturing and use in the UK. For example, while the paper identifies the human carcinogenic toxicity category as having the highest impact, it provides limited discussion on specific interventions or strategies that could be adopted to mitigate these impacts. Offering more concrete suggestions for industry practice or policy interventions, potentially informed by a comparison with best practices in other contexts or industries, would make the paper more actionable for readers.

·         Although the direct application of non-volatile memory technology to plasterboard life cycle assessment (LCA) might not be immediately obvious, the principles underlying the study "Enduring non-volatile L1 cache using low-retention-time STTRAM cells" offer intriguing parallels to the quest for durable, sustainable construction materials. This paper's exploration of enhancing the efficiency and endurance of computing systems echoes the construction industry's ongoing efforts to develop materials that are not only environmentally sustainable but also durable and efficient over their lifecycle. Incorporating a discussion on this work within your manuscript could illuminate the conceptual similarities between achieving technological advancements in computing and striving for sustainability in materials engineering. This analogy could be particularly resonant in sections of your paper that delve into the broader implications of sustainability, perhaps in the introduction or when discussing sustainable practices and material choices in construction (possibly Section 1.3 or 4). Drawing on the innovations in non-volatile memory technology as a metaphor could enrich the narrative around sustainable material development in the construction sector, highlighting the cross-disciplinary relevance of efficiency and endurance.

·         The utilization of optimization techniques, such as particle swarm optimization, for improving efficiency and sustainability, as demonstrated in "Optimizing Power Balance and Communication links in Microgrids: A Clustering Approach Using Particle Swarm Optimization", aligns with the themes of your paper on enhancing plasterboard production's environmental performance. Although their study focuses on microgrids, the methodological approach they present could offer valuable insights into your discussions on sustainability and efficiency improvements in plasterboard production processes. Referencing this work in your discussions on future methodological improvements or in the context of optimizing energy consumption in plasterboard production (sections discussing future research directions or methodology enhancements) would highlight the interdisciplinary approaches needed to reduce environmental impacts in the construction sector.

·         Although your paper primarily addresses environmental assessments of construction materials, the application of deep learning for predicting energy demands in buildings, as explored in "Deep learning hyperparameter optimization: Application to electricity and heat demand prediction for buildings" presents an innovative approach that could be paralleled in optimizing plasterboard production processes for better sustainability outcomes. Mentioning this work could be highly relevant in sections where future research directions are discussed, particularly in suggesting advanced analytical methods for enhancing the precision of environmental impact assessments or for optimizing the use of materials in construction to reduce energy consumption and emissions.

·         The exploration of gamification to engage and educate future engineers on construction principles in "Gamification in construction engineering education: A scoping review" could be mentioned in your paper as an innovative approach to promoting sustainability in construction practices. Particularly in sections discussing the broader implications of your findings for education and industry practices, this reference could underscore the importance of integrating sustainability concepts into construction engineering curricula, potentially through gamified learning experiences, to foster a new generation of professionals adept at incorporating environmental considerations into their work.

·         Lines 665-718: While the paper acknowledges limitations such as the exclusion of certain life cycle phases and reliance on secondary data, it could further explore the implications of these limitations for the study's conclusions. Additionally, proposing specific future research directions that address these limitations would be valuable. For instance, future studies could focus on collecting primary data for the UK context or exploring the life cycle impacts of alternative plasterboard materials and recycling technologies. Highlighting these areas could guide subsequent research efforts and contribute to a more comprehensive understanding of plasterboard's environmental impacts.

Author Response

The authors would like to thank the reviewers for their constructive comments and suggestions.

The attached table comprises comments made by the reviewers and the respective author’s responses and/or amendments arising. Changes are shown in yellow; Please note page numbering below may be slightly different in the amended version of the paper.

Author Response File: Author Response.pdf

Reviewer 4 Report

The current questions I have have been resolved and can be considered for publication in journals

Author Response

The authors would like to thank the reviewers for their constructive comments and suggestions.