Evaluating the Circular Economy Potential of Modular Construction in Developing Economies—A Life Cycle Assessment

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this paper, the authors evaluate the circular economy potential of modular construction by life cycle assessment. However, the following problems need to be solved before it is accepted for publication.

1.  Life cycle assessment is a classical approach. What the authors have done seems to utilize the method in modular building units of different reuse percentage. Please highlight the novelties of this paper.

2. Lots of citations in this manuscript are unable to be displayed correctly. Please check and correct.

3. The qualities of figures need to be improved.

 

 

Comments on the Quality of English Language

The English expression is easy to understand. But some minor editing is still required to correct the grammar and spelling mistakes.

Author Response

Dear Reviewer 1, 

On behalf of all the atuhors I would like to thank your time and efforts to provide constructive critisicm on the manuscript. 

The attached provide a detailed explanation for the comments addressed. 

Thank you 

Kind Regards,

Malindu

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

1.       Many citation errors occurred in the manuscript and need to be fixed.

2.       Table 1, what is the difference between this study and existing studies should be underlined.

3.       The quality of figures 4-7 is low, they should be redrawn in a more formal manner.

4.       5.4, more discussion should be provided on the strategies, especially, the proposed strategies should be connected with the results in section 5.

5.       The authors analyzed multiple impact categories, is there any relationship between the results of different impact categories that need to be examined?

 

Comments on the Quality of English Language

Minor editing of English language required

Author Response

Dear Reviewer 2, 

On behalf of all the atuhors I would like to thank your time and efforts to provide constructive critisicm on the manuscript. 

The attached provide a detailed explanation for the comments addressed. 

Thank you 

Kind Regards,

Malindu

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors,

I read your manuscript Evaluating the Circular Economy Potential of Modular Construction – A Design Stage Life Cycle Assessment. Please find below my comments to your work:

Sections 1 / Introduction and 2 / Background are well written yet contain some already known facts.  At least please change the titles of sections 2.1 and 2.2. because your research does not start with the explanation of the notion of CE, for example.

More should be said about the Sri Lanka context relevant to the work. The current version of the manuscript does not allow to get a comprehensive image of it and the results seem not be providing a response that suits Sri Lanka conditions. Please, provide an addition here.

As regards purpose of the designed modular unit: multipurpose use can be realistic, but within a certain range. E.g., the treatment unit demands significantly different conditions compared to the restaurant or office space, in terms of light (window size), applied materials, etc. Therefore, please narrow the scope of possible uses.

The height of the unit is also problematic, i.e., insufficient compared to the standards.  The unit either needs to be of an increased height or its use can only be for a very short period. Another problem of this design is insufficient air volume and in relation to that a questionable indoor air quality, which further implies more mechanical systems needed for air conditions, and then more energy demand, all of which reduces the level of sustainability-related quality. Hence, these facts must be considered when assigning purpose to the modular unit. Please provide explanations and revise this section of your text.

An explanation from the environmental standpoint and local/regional practice must be provided regarding selection of materials intended for modular unit. E.g., why this unit and its components could not have been made of wood? Why did you select steel?

The numbers of tables are wrong. Please, correct.

In the table starting from line 272 (Life cycle inventory, main material quantities), unit for aluminum is m²?

The quality of figures 3, 4, 5 and 6 should be improved.

The results of this research are precise in mathematical terms. In science, however, the benefits of reusing steel, iron, aluminum and glass in terms of sustainability and circularity are already proved. So, what novelty does this research bring to the existing body of published works?

It would be useful to convert the calculated impact amounts presented in table 8 into impact per material unit. Results presented in that way would be more beneficial for professionals out of the research sphere, and better understandable to relevant actors and decision-makers who hold enough power to start or accelerate national transition towards CE.

The claim that LCA is seldom carried out in the design stage is questionable. Please, provide proof (references) for it. The same phrase appears in the title, please consider this again.

Finally, please, carry out the proofreading. English is fine and clear overall, however there exist multiple typing/formatting errors.

Kind regards.

Comments on the Quality of English Language

Minor editing of English language required. 

Author Response

Dear Reviewer 3, 

On behalf of all the atuhors I would like to thank your time and efforts to provide constructive critisicm on the manuscript. 

The attached provide a detailed explanation for the comments addressed. 

Thank you 

Kind Regards,

Malindu

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The topic of the paper is good. However, the next comments have to be addressed:

1.     The language must be revised.

2.     Some abbreviations have been mentioned without any illustrations.

3.     The scope of the study, aims, and objectives are not clear at all.

4.     What this means Error! Reference source not found?

5.     The abstract and introduction do not reflect the scope of the paper.

6.     Introduction

·        The gap that the study will address is not clear or has not been presented.

·        The contributions of the paper to knowledge body are not clear or have not been presented.

7.     Background and Research Significance

·        This section presents some information or benefits regarding CE and MC. However, the contributions and gaps of the prior works have not been mentioned.

·        Table 1 has been presented without any relation to the paragraphs of the paper.

8.     Research Methodology

·        The methodology has not been arranged. For example, you list the goal and scope in the methodology. This is not appropriate.

·        The steps of the methodology are not presented well. So, it must be represented.

9.     Results and Discussion

·        You list the results. However, they have been discussed along with the prior literature.

·        5.3 Research Significance. The place of this section is not appropriate.

10.                        The practical implications have not been presented.

 

 

Comments on the Quality of English Language

Moderate

Author Response

Dear Reviewer 4, 

On behalf of all the atuhors I would like to thank your time and efforts to provide constructive critisicm on the manuscript. 

The attached provide a detailed explanation for the comments addressed. 

Thank you 

Kind Regards,

Malindu

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript is well revised according to my comments. 

Reviewer 2 Report

Comments and Suggestions for Authors

the comments are satisfied.

Comments on the Quality of English Language

Minor editing of English language required