Life Cycle Assessment of Forest-Based Products: A Review

Round 1

Reviewer 1 Report

The topic of the manuscript is important and of interest to the readers. The authors aim to review energy use, emissions, and other environmental effects during the production of forest-based products. Authors have made significant efforts to review literature studies on major forest-based products, however, the manuscript lacks the focus. Also, the authors have mostly compiled the findings from other studies without providing much of their own critical discussion. Text in the manuscript is repetitive in some places. This review would improve significantly by removing or shortening the text on Markets: Status and Trends, and adding more discussion on the studies compiled in the manuscript. Some other suggestions are provided below:

Delete line 32 Please delete lines 52 to 58. Similar information is provided in the previous text. Line 118: Why only from 2005 to 2019? Authors might need to provide justification or discuss more about it. If there are review papers that cover life cycle analysis studies before 2005, authors should cite those papers here. I believe figure 3 and its discussion is not important. It can be removed from the manuscript. As the paper should focus more on the discussion on results and findings of studies on life cycle assessment of based products, I believe section 3 (Forest Resources, Products, and Markets: Status and Trends) is not significant for this paper. If authors want to include this information, they need to shorten this section. Some information (e.g., lines 262-262, Fig. 10) is very well known and should definitely be removed from the manuscript. Line 285 – 289: This is again introductory text. I suggest authors to delete all this type of text from the later sections of the manuscript and focus mainly on the observations and discussion of results from the literature studies. There is not much significance of table 1 as by itself. It should be combined with table 2 to present in a better way.

Author Response

We appreciate reviewers for their valuable comments on this manuscript. The responses to those comments were accommodated in the revised version of the manuscript.

Reviewer #1:

Overall Comment: The topic of the manuscript is important and of interest to the readers. The authors aim to review energy use, emissions, and other environmental effects during the production of forest-based products. Authors have made significant efforts to review literature studies on major forest-based products, however, the manuscript lacks the focus.

Response: Thank you. We appreciate your comments. We have revised and improved the manuscript to bring the focus on the life-cycle assessment of forest-based products.

Comment: Also, the authors have mostly compiled the findings from other studies without providing much of their own critical discussion. Text in the manuscript is repetitive in some places. This review would improve significantly by removing or shortening the text on Markets: Status and Trends, and adding more discussion on the studies compiled in the manuscript. Some other suggestions are provided below:

Response: Thank you. We have added critical discussions regarding each product and an overall discussion related to various aspects of life-cycle assessment of forest-based products in section 5.

Comment: This review would improve significantly by removing or shortening the text on Markets: Status and Trends, and adding more discussion on the studies compiled in the manuscript.

Response: Thank you. We have reduced the “Markets: Status and Trends” substantially and added more discussions to each product category. However, this section provides a brief and comprehensive status of the wood products market, which is very essential for researchers, especially who are new to this research area.

Comment: Delete line 32 Please delete lines 52 to 58. Similar information is provided in the previous text.

Response: Thank you. Revised.

Comment: Line 118: Why only from 2005 to 2019? Authors might need to provide justification or discuss more about it. If there are review papers that cover life cycle analysis studies before 2005, authors should cite those papers here.  

Response: Thank you. The revised study include published articles from 1997 until 2019.  

Comment: I believe figure 3 and its discussion is not important. It can be removed from the manuscript.

Response: Thank you. Removed.

Comment: As the paper should focus more on the discussion on results and findings of studies on life cycle assessment of based products, I believe section 3 (Forest Resources, Products, and Markets: Status and Trends) is not significant for this paper. If authors want to include this information, they need to shorten this section.

Response: Thank you. We have reduced section 3 substantially and added more discussions to each product category. However, section 3 provides a brief and comprehensive status of the wood products market, which is very essential for researchers, especially who are new to this research area.

Comment: Some information (e.g., lines 262-262, Fig. 10) is very well known and should definitely be removed from the manuscript. Line 285 – 289: This is again introductory text. I suggest authors to delete all this type of text from the later sections of the manuscript and focus mainly on the observations and discussion of results from the literature studies.

Response: Thank you. Removed these sentences and also, we revised the manuscript based on reviewers’ comments.

Comment: There is not much significance of table 1 as by itself. It should be combined with table 2 to present in a better way.

Response: Thank you. Table 1 showed the critical information about the LCA study locations, system boundary, functional units, impact methods, and allocations. We believe this information is very important for the reader. Table 2 showed the results from various LCA studies for each wood products. We tried to combine table 1 and 2 but it was very crowded and did not fit into the current page width.

Reviewer 2 Report

This is a well-written article about a well-performed lit review of a very important topic. It is a great addition to the LCA literature. 

I made some editorial suggestions and comments, but my main observation is the way products were classified, more specifically considering "tall buildings" as a separate product. While I understand the purpose of doing this, it may not seem very logical to others, considering that tall buildings are made of other "traditional" and "emerging" products. Maybe the authors could elaborate a little more on the reason for this classification decision.

One suggestion, maybe for the non-initiated, some comparisons with other building materials could be provided. Some studies have this already "built-in" but maybe authors could include a few references and numbers. This would provide support for the assertions made in a couple of places about wood being "low impact" material.

Overall it is a very good paper.

Comments for author File: Comments.pdf

Author Response

We appreciate reviewers for their valuable comments on this manuscript. The responses to those comments were accommodated in the revised version of the manuscript.

Reviewer #2:

Overall Comment: This is a well-written article about a well-performed lit review of a very important topic. It is a great addition to the LCA literature.

Response: Thank you. We appreciate your comments.

Comment: I made some editorial suggestions and comments, but my main observation is the way products were classified, more specifically considering "tall buildings" as a separate product. While I understand the purpose of doing this, it may not seem very logical to others, considering that tall buildings are made of other "traditional" and "emerging" products. Maybe the authors could elaborate a little more on the reason for this classification decision.

Response: I elaborated on the linkage of including building systems which incorporate both traditional and emerging building products in their structure. The buildings themselves are the dispositions of the wood building products studied.

Comment: One suggestion, maybe for the non-initiated, some comparisons with other building materials could be provided. Some studies have this already "built-in" but maybe authors could include a few references and numbers. This would provide support for the assertions made in a couple of places about wood being "low impact" material.

Response: The major focus was on building systems to show impacts compared to alternative materials.  

Comment: Overall it is a very good paper.

Response: Thank you. We appreciate your comments.

Round 2

Reviewer 1 Report

Authors have made the suggested changes. The manuscript is acceptable in the present form.