A Review of Net-Zero Greenhouse Gas (GHG) Emission Non-Regulatory Environmental Building Standards and Frameworks

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper engages with a timely and important topic in sustainable architecture. I read the manuscript carefully and believe it offers value but requires substantial revisions before it can be considered for publication. Below are my detailed comments to help the authors strengthen the work.

1.Much of the content (particularly Sections 3–6) is descriptive and lacks a clear analytical structure. I recommend that the authors develop an explicit comparative framework early in the paper—ideally in the introduction or methodology. For example, presenting a typology or matrix to categorize standards by compliance mechanism, performance verification, scope of metrics, and policy integration would help organize the discussion systematically.

2.The manuscript notes that net-zero standards are intended to address performance gaps but does not provide evidence on whether they succeed. To make this claim more credible, please incorporate empirical studies or case examples showing whether post-occupancy verification has demonstrably improved GHG outcomes. If such data are scarce, acknowledge this limitation explicitly.

3.It is sometimes unclear which standards are global and which are region-specific. Please clarify this distinction throughout the analysis. For instance, in Sections 5 and 6 and in any tables, indicate whether a standard applies internationally or only in certain jurisdictions, and discuss how local regulatory or policy contexts shape its development.

4.Although the paper mentions carbon offsets as a component of net-zero certification, it does not engage critically with the extensive literature questioning offsets’ reliability and risks (e.g., additionality, permanence, moral hazard). Adding a section or paragraph to summarize these debates and discuss how reliance on offsets affects the credibility of net-zero claims would significantly improve the paper.

5.A large proportion of the sources cited are from organizational reports or websites rather than peer-reviewed literature. This reliance limits the scholarly rigor of the work. Please discuss this limitation in the discussion section and suggest that more empirical, peer-reviewed research is needed in this area.

6.Key terms like “NZGGEBS,” “net-zero carbon standards,” and “zero-energy buildings” are sometimes used interchangeably or without clear definitions. I strongly recommend including a concise glossary or definition table early in the text and ensuring consistent terminology throughout.

7.The conclusion summarizes the findings well but does not offer clear, actionable recommendations for policymakers, practitioners, or standard-setting organizations. Expanding the conclusion to include specific policy suggestions—such as harmonization of metrics, improved transparency, and independent verification—would enhance the paper’s practical value.

I hope these comments help the authors to substantially improve the clarity, rigor, and impact of their manuscript.

 

Author Response

This paper engages with a timely and important topic in sustainable architecture. I read the manuscript carefully and believe it offers value but requires substantial revisions before it can be considered for publication. Below are my detailed comments to help the authors strengthen the work. 1.Much of the content (particularly Sections 3–6) is descriptive and lacks a clear analytical structure. I recommend that the authors develop an explicit comparative framework early in the paper—ideally in the introduction or methodology. For example, presenting a typology or matrix to categorize standards by compliance mechanism, performance verification, scope of metrics, and policy integration would help organize the discussion systematically. The paper adopts a comparative policy analysis method explained in the methodology (please see Figure 2. Research methodology diagram and the corresponding text in Section 2 of the manuscript). We have revised the titles in Sections 3-6 and reviewed and revised the content to be better aligned with the methodology. Please also note that a detailed matrix/table of the first generation of Environmental Building Standards (EBS) and the newly developed Net Zero Green House Gas Emission Building Standards (NZGHGEBS) is effectively presented in Tables 1 & 2 respectively and referred to in the analysis provided in the main body of the text. 2.The manuscript notes that net-zero standards are intended to address performance gaps but does not provide evidence on whether they succeed. To make this claim more credible, please incorporate empirical studies or case examples showing whether post-occupancy verification has demonstrably improved GHG outcomes. If such data are scarce, acknowledge this limitation explicitly. Thank you for this important comment. We have added a statement in the revised manuscript to address this comment as follows: “…It should, however, be noted that most NZGHGEBS are recently developed and there is still a lack of strong empirical evidence to demonstrate whether these standards are succeeding to deliver net zero carbon emissions in practice. Studies carried out on early examples of the implementation of these standards suggest that while net zero designed buildings perform better than the rest of the building stock, they still suffer from the problem of the performance gap. This reinforces the necessity of a shift towards an outcome-focused design and procurement approach [127]. 3.It is sometimes unclear which standards are global and which are region-specific. Please clarify this distinction throughout the analysis. For instance, in Sections 5 and 6 and in any tables, indicate whether a standard applies internationally or only in certain jurisdictions, and discuss how local regulatory or policy contexts shape its development. We have revised Tables 1 and 2 to make this point clear. As these standards are non-regulatory, their adoption in different countries and regions is not driven by legislation and is primarily driven by market mechanisms, although the endorsement of local authorities and public bodies often play a major role in their local traction. 4.Although the paper mentions carbon offsets as a component of net-zero certification, it does not engage critically with the extensive literature questioning offsets’ reliability and risks (e.g., additionality, permanence, moral hazard). Adding a section or paragraph to summarize these debates
and discuss how reliance on offsets affects the credibility of net-zero claims would significantly improve the paper. Thank you for this insightful comment. We have added a statement to the revised manuscript to address this comment: “…However, there are several potential issues that could compromise the role of carbon offsets in reducing emissions and achieving net zero greenhouse gas emissions. For example, verifying the additionality of a carbon offsetting project, meaning that any reduction in emissions is only caused by the offset project taking place, is challenging. There are also risks associated with carbon leakages and reversals [123]. Therefore, priority should always be given to reducing or eliminating emissions at source. For example, onsite renewables should be prioritised over carbon offsets, and the sequestration of carbon onsite (e.g. using structural timber) is preferable to biogenic sequestration offsite. Offsetting is generally regarded as a final step to be applied when benchmarks are met and should follow rigorous verification methods such as the guidelines provided in the latest edition of the Oxford Offsetting Principles [124].” 5.A large proportion of the sources cited are from organizational reports or websites rather than peer-reviewed literature. This reliance limits the scholarly rigor of the work. Please discuss this limitation in the discussion section and suggest that more empirical, peer-reviewed research is needed in this area. We have added a statement to the discussion part of the paper in the revised manuscript to address this very valid point: “Scarcity of peer-reviewed research covering robust and verifiable empirical data in the context of new NZGHGEBS is a limitation of this study. It is recommended that future review studies in this field address this limitation as and when more operational data is collated from new buildings designed and procured following these new standards.” Another statement is added to the methodology part to explain why citation to the grey literature and organizational reports or websites was necessary in this review: “A second step was a review of the grey literature including industry websites and publications with a particular focus on NZGHGEBS…The coverage of the grey literature in this study was necessary to identify the origins and the structure of several environmental standards.” 6.Key terms like “NZGGEBS,” “net-zero carbon standards,” and “zero-energy buildings” are sometimes used interchangeably or without clear definitions. I strongly recommend including a concise glossary or definition table early in the text and ensuring consistent terminology throughout. Thank you for this comment. We have tried to address this comment in the text. The text clarifies that NZGHGEBS and Net Zero Carbon Standards are indeed used interchangeably the first time these terms are used in Introduction: “Section 5 outlines the characteristics of Net-Zero Greenhouse Gas Emission Building Standards (NZGHGEBS), often referred to as ‘Net Zero Carbon Standards’ with reference to international standards…” The term nearly zero-energy buildings used in the European Directive for Energy Performance of Buildings (EPBD) is now defined in the revised version of the manuscript: “The European Energy Performance of Buildings Directive (EPBD) in 2010 [64] required all new building built after 2020 to be ‘nearly zero-energy’, meaning they must have a high energy performance and very low-energy needs covered largely by onsite and nearby renewable energy sources. This directive required Member States to define ‘nearly zero-energy’ in their national building regulations and to facilitate a transition to nearly zero-energy buildings.”
7.The conclusion summarizes the findings well but does not offer clear, actionable recommendations for policymakers, practitioners, or standard-setting organizations. Expanding the conclusion to include specific policy suggestions—such as harmonization of metrics, improved transparency, and independent verification—would enhance the paper’s practical value. The conclusion section of the paper is revised to address this comment as follows: “The review presented in this paper points to the following key requirements that can help maximize the benefits of the new generation of environmental building standards:
• Improved transparency in how the benchmarks and targets are derived, reconciling the bottom-up approach with the top-down approach
• Contractual arrangements to facilitate building fine tuning after completion and post-occupancy evaluations (including post-construction LCA audits to cover both operational and embodied carbon)
• Robust measurement and verification protocols to demonstrate the effectiveness of these standards in practice, using third party independent verification” I hope these comments help the authors to substantially improve the clarity, rigor, and impact of their manuscript. Thank you very much for the very helpful and constructive comments!

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript presents a comprehensive and timely comparative review of non-regulatory Net-Zero Greenhouse Gas Emission Building Standards (NZGGEBS), tracing their evolution in response to the Paris Agreement and global decarbonization efforts. The scope, global coverage, and detailed mapping of standard characteristics make this a potentially valuable reference for researchers, policymakers, and practitioners.

The manuscript, in its current form, falls short of the analytical depth and originality expected of a publishable research article. I recommend major revisions before reconsideration.

Major Improvement

Lack of Conceptual Framework or Typology

The manuscript is highly descriptive but does not propose a theoretical or conceptual framework to organize the observed trends. A typology categorizing NZGGEBS by logic (top down vs. bottom up), rigor, offset dependence, and temporal scope would enhance its originality and academic utility.

Insufficient Critical Engagement

In the outline general criticisms of older EBS, there is little interrogation of the new performance-based standards.

• The legitimacy and accountability of offset mechanisms
• Enforcement challenges in voluntary frameworks
• Risks of regional bias in benchmark setting
• Opaque data behind carbon benchmarks

A more critical stance is needed, both on where these standards succeed and where they remain vulnerable.

Limited Case-Based Evidence

The paper would benefit significantly from incorporating 2-3 brief real-world examples or case studies that illustrate how specific NZGGEBS are applied (or fail) in practice, including:

• Data collection and management issues
• Enforcement of post-occupancy metrics
• Cost trade-offs or rebound effects

Visual Communication

Although the tables are strong, additional visual aids could improve clarity and comparative impact:

• A timeline charting the evolution of key standards
• A radar plot showing compliance features (transparency, rigor, performance validation)
• A heatmap comparing scope and targets across regions

Similarity Check

I have reviewed the iThenticate report, which indicates an overall similarity index of 22%. While this does not constitute plagiarism; since the majority of individual matches are below 1%. It is generally advisable to aim for a similarity score below 15% to enhance the manuscript's overall originality.

Minor Comments

1. The abstract is well written but could be more concise and focused on key findings and contributions.
2. Redundant phrasing and repetitive section overlaps (especially in Sections 4–6) could be streamlined.
3. The terms NZGGEBS, EBS, and LCEBS appear frequently; consider providing a glossary or acronym table early in the manuscript.

Comments on the Quality of English Language

Some sections are very descriptive and long. They could benefit from a tighter rephrasing. Occasional repetition and minor grammatical inconsistencies should be addressed in revision to improve overall readability and flow. A careful language review is recommended prior to final submission. 

Author Response

Comments and Suggestions for Authors:
The manuscript presents a comprehensive and timely comparative review of non-regulatory Net-Zero Greenhouse Gas Emission Building Standards (NZGGEBS), tracing their evolution in response to the Paris Agreement and global decarbonization efforts. The scope, global coverage, and detailed mapping of standard characteristics make this a potentially valuable reference for researchers, policymakers, and practitioners.
The manuscript, in its current form, falls short of the analytical depth and originality expected of a publishable research article. I recommend major revisions before reconsideration.
Major Improvement
Lack of Conceptual Framework or Typology
The manuscript is highly descriptive but does not propose a theoretical or conceptual framework to organize the observed trends. A typology categorizing NZGGEBS by logic (top down vs. bottom up), rigor, offset dependence, and temporal scope would enhance its originality and academic utility.
Thank you for this comment. The paper adopts a comparative policy analysis method explained in the methodology (please see Figure 2. Research methodology diagram and the corresponding text in Section 2 of the manuscript). We have revised the titles in Sections 3-6 and reviewed and revised the content to be better aligned with the methodology. Please also note that a detailed matrix/table of the first generation of Environmental Building Standards (EBS) and the newly developed Net Zero Green House Gas Emission Building Standards (NZGHGEBS) is presented in Tables 1 & 2 respectively and referred to in the analysis provided in the main body of the text. These tables include details such as the data sources, certificate awarding period, assessment criteria, compliance level, targets/benchmarks, approaches to offsetting that is systematically presented.
Insufficient Critical Engagement
In the outline general criticisms of older EBS, there is little interrogation of the new performance-based standards.
•
The legitimacy and accountability of offset mechanisms
•
Enforcement challenges in voluntary frameworks
•
Risks of regional bias in benchmark setting
•
Opaque data behind carbon benchmarks
A more critical stance is needed, both on where these standards succeed and where they remain vulnerable.
Thank you for these insightful comments. We have considered these comments in the revised manuscript and made several changes to address these points. For example, the following paragraph is added about carbon offsetting:
“…However, there are several potential issues that could compromise the role of carbon offsets in reducing emissions and achieving net zero greenhouse gas emissions. For example, verifying the additionality of a carbon offsetting project, meaning that any reduction in emissions is only caused by the offset project taking place, is challenging. There are also risks associated with carbon leakages and reversals [123]. Therefore, priority should always be given to reducing or eliminating emissions at source. For example, onsite renewables should be prioritised over carbon offsets, and the sequestration of carbon onsite (e.g. using structural timber) is preferable to biogenic sequestration offsite. Offsetting is generally regarded as a final step to be applied when benchmarks are met and should follow rigorous verification methods such as the guidelines provided in the latest edition of the Oxford Offsetting Principles [124].”
We have also added the following paragraph to the conclusion section to highlight the significance of data transparency and the role of contractual arrangements to facilitate implementation and verification of net-zero standards:
“The review presented in this paper points to the following key requirements that can help maximize the benefits of the new generation of environmental building standards:
•
Improved transparency in how the benchmarks and targets are derived, reconciling the bottom-up approach with the top-down approach
•
Contractual arrangements to facilitate building fine tuning after completion and post-occupancy evaluations (including post-construction LCA audits to cover both operational and embodied carbon)
•
Robust measurement and verification protocols to demonstrate the effectiveness of these standards in practice, using third party independent verification”
Limited Case-Based Evidence
The paper would benefit significantly from incorporating 2-3 brief real-world examples or case studies that illustrate how specific NZGGEBS are applied (or fail) in practice, including:
•
Data collection and management issues
•
Enforcement of post-occupancy metrics
•
Cost trade-offs or rebound effects
Thank you or this comment. In the revised manuscript, we have acknowledged the scarcity of robust empirical data to evaluate the effectiveness of the new standards in practice and recommended this as future research as and when this data becomes more available at scale:
“It should, however, be noted that most NZGHGEBS are recently developed and there is still a lack of strong empirical evidence to demonstrate whether these standards are succeeding to deliver net zero carbon emissions in practice. Studies carried out on early examples of the implementation of these standards suggest that while net zero designed buildings perform better than the rest of the building stock, they still suffer from the problem of the performance gap. This reinforces the necessity of a shift towards an outcome-focused design and procurement approach [127]. Scarcity of peer-reviewed research covering robust and verifiable empirical data in the context of new NZGHGEBS is a limitation of this study. It is recommended that future review studies in this field address this limitation as and when more operational data is collated from new buildings designed and procured following these new standards. It will also be important to investigate potential cost trade-offs and rebound effects in implementation of these standards in practice. At the time of writing, several pilot projects have submitted their performance data to the newly developed Net Zero Carbon Building Standard in the UK [85], which could be analysed and used to evaluate the effectiveness of the standard and identify improvement opportunities.”
”
Visual Communication
Although the tables are strong, additional visual aids could improve clarity and comparative impact:
•
A timeline charting the evolution of key standards
•
A radar plot showing compliance features (transparency, rigor, performance validation)
•
A heatmap comparing scope and targets across regions
Thank you for this comment. We have added a Figure in the revised manuscript that shows a timeline that reflects the evolution of environmental building standards (Figure 1. Timeline for the introduction of major Environmental Building Standards covered in this article.)
We avoided a subjective assessment of the standards (e.g. the rigor of standards). However, there is a lot of systematic data and information available in Tables 1 & 2 for the prospective readers to develop their understanding of these standards.
Similarity Check
I have reviewed the iThenticate report, which indicates an overall similarity index of 22%. While this does not constitute plagiarism; since the majority of individual matches are below 1%. It is generally advisable to aim for a similarity score below 15% to enhance the manuscript's overall originality.
As you pointed out, the similarity in individual matches is typically below 1%. The overall similarity index probably reflects the large number of citations and references in the paper (138 references), which is higher than most typical research articles.
Minor Comments
1.
The abstract is well written but could be more concise and focused on key findings and contributions.
2.
Redundant phrasing and repetitive section overlaps (especially in Sections 4–6) could be streamlined.
3.
The terms NZGGEBS, EBS, and LCEBS appear frequently; consider providing a glossary or acronym table early in the manuscript.
Comments on the Quality of English Language:
Some sections are very descriptive and long. They could benefit from a tighter rephrasing. Occasional repetition and minor grammatical inconsistencies should be addressed in revision to improve overall readability and flow. A careful language review is recommended prior to final submission.
Thank you very much for the very helpful and constructive comments. The abstract is shortened, and the entire text has been proofread and revised following your comments. The terms NZGGEBS (changed to NZGHGEBS in the revised manuscript) and EBS are clearly defined the first time used in the text. The term LCEBS was used only once in the text and is now changed to ‘low carbon’ environmental building standard (EBS).

Reviewer 3 Report

Comments and Suggestions for Authors

Thank you for your valuable manuscript. The following suggestions are offered to help strengthen and improve your study:

1. State a crisp research question. The introduction sketches context but never crystallizes a single guiding RQ or hypothesis. Add one sentence that pinpoints the knowledge gap you fill (Lines 27-33).
2. Differentiate from prior reviews. You list earlier EBS comparisons but should specify how your NZGGEBS synthesis extends beyond Doan 2017 or Satola 2022 (Lines 34-65).
3. Show a PRISMA-style flow chart. The methods outline search strings but omit a diagram of identification → screening → inclusion. Include one and an appendix of excluded standards (Lines 108-137).
4. Justify English-only bias. Acknowledge how excluding non-English standards might skew findings, or describe mitigation (e.g., expert validation) (Lines 148-166).
5. Quantify “significantly fewer criteria.” Convert Table 2 narrative into numbers (e.g., median # metrics) and supply a simple statistical test (Lines 533-538).
6. Correct taxonomy in Tables 2 & 3. LEED Zero is an add-on to LEED, not a stand-alone NZGGEBS; adjust classification/footnote (Lines 569-575).
7. Deepen embodied-carbon analysis. Present a small data graphic (histogram/box plot) illustrating the embodied-carbon shares cited in literature (Lines 475-505).
8. Critique offsetting quality. Expand on the role of ICROA/ICVCM and the greenwashing risk when offsets substitute in-use cuts (553-559).
9. Elevate policy implications. Your point about the “regulatory void” is buried; move a concise version to Abstract or Introduction for impact (Lines 739-744).
10. Offer remedies for future ‘performance gaps.’ You foresee new gaps (embodied carbon) but give no fixes; you propose post-construction LCA audits (Lines 766-769).
11. Language polish. Examples: “underpining” → “underpinning” (Method, line 88); “45 45-yearspan” duplicate (line 481). Engage a professional proofreader (Lines 88 and 481).
12. Self-contained figures. Figure 6 lacks a stand-alone caption clarifying data sources and abbreviations—add for reader clarity (Lines 623-627).
13. Specify numeric pass/fail thresholds. When claiming binary compliance (e.g., lines 535–536), cite actual target values in the main text or appendix.
14. Update references to 2024–2025 policy papers. You already cite the 2024 pilot UK NZC Standard (line 947); weave these latest documents into the Discussion to show currency.

 

 

 

 

Comments on the Quality of English Language

The paper would benefit from a careful language polish before resubmission. I suggest the authors:

1. Engage a native-English editor or a reputable professional editing service to correct spelling, grammar, and punctuation errors (for example, “underpining” should read “underpinning”).

2. Shorten sentences that run over 30 words and break overly long paragraphs into two or three concise units to improve readability.

3. Maintain one verb tense per section; the Methods should use past tense, while the Discussion can adopt present tense for interpretations.

4. Recheck references for uniform citation style and ensure figure captions are self-contained and free of unexplained abbreviations.

Author Response

Thank you for your valuable manuscript. The following suggestions are offered to help strengthen and improve your study:
1. State a crisp research question. The introduction sketches context but never crystallizes a single guiding RQ or hypothesis. Add one sentence that pinpoints the knowledge gap you fill (Lines 27-33). We have added a statement to the revised manuscript to address this point and highlight the key research questions addressed in this article: “The paper describes how, since 2015, prompted by the Paris Agreement [12] and greater awareness of Lifecycle Assessment (LCA) reframing the environmental impact of buildings [13,14], a new generation of EBS with the aim of defining and evaluating net-zero greenhouse gas (GHG) emission buildings have been developed (Figure 1). The key research questions here are: 1) have the Paris Agreement and growing awareness of the climate emergency made the new generation of EBS materially different from the first generation? And if so, 2) what are the unique characteristics and the implications of the newly developed EBS?”
2. Differentiate from prior reviews. You list earlier EBS comparisons but should specify how your NZGGEBS synthesis extends beyond Doan 2017 or Satola 2022 (Lines 34-65). Thank you for this comment. Doan et al. (2017) article provides a comparison between pre-2015 environmental rating schemes such as BREEAM and LEED. Satola et al. (2022) study covers different approaches to net zero carbon delving into several case studies and the specific design measures used to reduce operational and embodied carbon emissions. The present article, however, compares the pre-2015 (Paris agreement) EBS with the newly developed NZGHGEBS standards and demonstrates how the approaches and metrics used to evaluate the environmental performance of buildings have evolved over the past few years. None of the previous articles cited above carry out such a critical comparison.
3. Show a PRISMA-style flow chart. The methods outline search strings but omit a diagram of identification → screening → inclusion. Include one and an appendix of excluded standards (Lines 108-137). The search terms used for literature review, the databases used and the review process including the number of references found in the initial and final screening are provided in Section 2 and Figure 3 of the article.
4. Justify English-only bias. Acknowledge how excluding non-English standards might skew findings, or describe mitigation (e.g., expert validation) (Lines 148-166). The article explains the use of English language may have created a bias in our literature review. However, the manuscript explains that our research covered standards with information available in other languages as well: “Where a standard was identified but the detailed information was in a language other than English, Google Translate was used to translate key documents.”
We have now provided further elaboration and, whilst acknowledging the limitation, cite explicit examples of non-English standards covered in the study: “…it should be recognised that the use of English language searches for the second part of the investigation may have favoured the identification of English language NZGHGEBS. Whilst, this was a limitation of the study, key NZGHGEBS originally developed in non-English speaking countries such as Germany (DGNB Climate Positive), France (Energie Positive & Reduction Carbone), and Sweden (Miljöbyggnad) were covered in this study.”
5. Quantify “significantly fewer criteria.” Convert Table 2 narrative into numbers (e.g., median # metrics) and supply a simple statistical test (Lines 533-538). The weight of lifecycle and embodied carbon credits in few key pre-2015 EBS such as LEED and BREEAM are provided to show the weight of these credits in the first generation of EBS. Table 2 shows that embodied carbon and LCA are an essential component of the new generation of EBS post-2015 (Paris Agreement).
6. Correct taxonomy in Tables 2 & 3. LEED Zero is an add-on to LEED, not a stand-alone NZGGEBS; adjust classification/footnote (Lines 569-575). This is explained in the manuscript as follows: “LEED Zero is another global NZGHGEBS launched in the same year as the ILFI Zero Carbon Certification. However, unlike ILFI Zero Carbon Certification, it is an adjunct to existing LEED standards rather than a stand-alone standard and full LEED certification is required before this standard can be applied [15]. LEED Zero is one of a few instances where a NZGHGEBS has been attached to an EBS and this is interesting for two reasons: firstly, other global organisations with EBS, such as ILFI, have launched new NZGHGEBS rather than attach new requirements to existing standards; and secondly, other organisations, notably the BRE, whilst advocating Net Zero [118] have decided not to produce a similar addendum to their own standards.” We have also added the term ‘(adjunct to LEED EBS)’ to Table 2 in the revised manuscript to further clarify this where LEED Zero Carbon standard is covered.
7. Deepen embodied-carbon analysis. Present a small data graphic (histogram/box plot) illustrating the embodied-carbon shares cited in literature (Lines 475-505). Thank you for this comment. The data provided in references is not quite comparable to facilitate an info graphic about this. For example, the LETI share of 34% attributed to embodied and lifecycle carbon is based on a 60-year analysis in accordance with the RICS protocol, whereas the figure provided by Lausselet et al. (2021) study provides the share of embodied carbon of material replacements over a 45-year lifespan. We have provided several examples of the share of embodied carbon in the text (both in terms of weighting in EBS credits and the share of carbon emissions).
8. Critique offsetting quality. Expand on the role of ICROA/ICVCM and the greenwashing risk when offsets substitute in-use cuts (553-559). We have added the following paragraph to the revised manuscript to address this important comment: “However, there are several potential issues that could compromise the role of carbon offsets in reducing emissions and achieving net zero greenhouse gas emissions. For example, verifying the additionality of a carbon offsetting project, meaning that any reduction in emissions is only caused by the offset project taking place, is challenging. There are also risks associated with carbon leakages and reversals [123]. Therefore, priority should always be given to reducing or eliminating emissions at source. For example, onsite renewables should be prioritised over carbon offsets, and the sequestration of carbon onsite (e.g. using structural timber) is preferable to biogenic sequestration offsite. Offsetting is generally regarded as a final step to be applied when benchmarks are met and should follow rigorous verification methods such as the guidelines provided in the latest edition of the Oxford Offsetting Principles [124].”
9. Elevate policy implications. Your point about the “regulatory void” is buried; move a concise version to Abstract or Introduction for impact (Lines 739-744). This paragraph is now moved to the introduction, and a concise statement also refers to this regulatory void and the role of these standards in the conclusion section: “The study highlights the role of NZGHGEBS in filling the regulatory void left by insufficient national legislation. These standards, often developed by private institutions or professional coalitions, are increasingly being adopted by developers, municipalities, and industry bodies seeking to align with climate targets. Their influence is likely to grow, particularly if regulatory frameworks continue to lag behind the ambitions of the construction and real estate sectors.”
10. Offer remedies for future ‘performance gaps.’ You foresee new gaps (embodied carbon) but give no fixes; you propose post-construction LCA audits (Lines 766-769). A new paragraph is added in the revised manuscript to highlight key requirements emerging from the study. This includes a recommendation for post-construction LCA audits to cover both operational and embodied carbon: “The review presented in this paper points to the following key requirements that can help maximize the benefits of the new generation of environmental building standards:
• Improved transparency in how the benchmarks and targets are derived, reconciling the bottom-up approach with the top-down approach
• Contractual arrangements to facilitate building fine tuning after completion and post-occupancy evaluations (including post-construction LCA audits to cover both operational and embodied carbon)
• Robust measurement and verification protocols to demonstrate the effectiveness of these standards in practice, using third party independent verification”
11. Language polish. Examples: “underpining” → “underpinning” (Method, line 88); “45 45-yearspan” duplicate (line 481). Engage a professional proofreader (Lines 88 and 481). Thank you for this helpful comment. Both typos cited here are corrected and the manuscript is reviewed and proofread.
12. Self-contained figures. Figure 6 lacks a stand-alone caption clarifying data sources and abbreviations—add for reader clarity (Lines 623-627). Thank you for this helpful comment. We have revised the caption accordingly.
13. Specify numeric pass/fail thresholds. When claiming binary compliance (e.g., lines 535–536), cite actual target values in the main text or appendix. Examples are provided in the text and key targets/benchmarks are covered in Table 2 (‘Targets/Benchmarks column). Example of citation in the text of the manuscript:
“… ILFI Zero Carbon Certification standard is significant because it has many features typical of the other zero GHG emissions standards. The features include certification awarded after practical completion (one year in this case) and based on performance data including metered data and records of built material types and quantities [117]. In addition, embodied energy is a key metric and a target of 500kg C02e/m² is set for the carbon emission associated with the construction of a building, sometimes referred to as the upfront carbon (cradle to gate or RICS A1-A5). Targets for operational energy are based on climatic zone are as follows: for American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) climate zones: 0, 1, 2A, 2B, 5A, 5B, 7, or 8 a target of 101 kwh/m²/year; and for all other ASHRAE climate zones the target is 88 kwh/m²/year.”
14. Update references to 2024–2025 policy papers. You already cite the 2024 pilot UK NZC Standard (line 947); weave these latest documents into the Discussion to show currency. Thank you for this helpful comment. We have added a statement about the net zero pilot projects in the UK and how these could inform future studies to the discussion section: “At the time of writing, several pilot projects have submitted their performance data to the newly developed Net Zero Carbon Building Standard in the UK [85], which could be analysed and used to evaluate the effectiveness of the standard and identify improvement opportunities.”
Comments on the Quality of English Language:
The paper would benefit from a careful language polish before resubmission. I suggest the authors:
1.
Engage a native-English editor or a reputable professional editing service to correct spelling, grammar, and punctuation errors (for example, “underpining” should read “underpinning”).
2.
Shorten sentences that run over 30 words and break overly long paragraphs into two or three concise units to improve readability.
3.
Maintain one verb tense per section; the Methods should use past tense, while the Discussion can adopt present tense for interpretations.
4.
Recheck references for uniform citation style and ensure figure captions are self-contained and free of unexplained abbreviations. Thank you very much for the very helpful and constructive comments. We have reviewed and revised the entire manuscript reflecting on the comments provided about the language style. All typos are corrected.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

You are to be commended for the effort put into addressing the previous round of comments, particularly regarding the inclusion of carbon offset critiques and the clarification of regional contexts within the tables. The manuscript has improved in its coverage of the grey literature and now offers a more complete inventory of the current landscape. However, while the descriptive breadth is sufficient, the analytical depth and logical consistency remain problematic. My comments below are intended to help strengthen the paper’s contribution by addressing several critical areas where the argumentation is still disconnected from the empirical evidence presented, and where the response to the previous call for a “comparative framework” feels superficial.

1.While you have attempted to address the previous feedback regarding the descriptive nature of the paper by introducing a “comparative policy analysis” methodology section, there remains a significant gap between this stated framework and the actual analysis performed. You cite Mayer et al.’s framework  to “clarify values and arguments,” yet the subsequent analysis in Sections 5 and 6 remains a technical list of metrics (e.g., energy use intensity, offset allowability) rather than an investigation into the institutional values or political dynamics that shaped them. For instance, the paper fails to explain why the UK context favored a voluntary professional coalition model like LETI , whereas the French context produced a state-aligned experimental framework like E+C-. Merely citing a policy analysis framework without applying it to explain these divergences renders the methodology section decorative rather than functional.

2.The central argument that Net-Zero GHG Emission Building Standards (NZGHGEBS) are characterized by a “binary pass or fail approach” is factually incorrect and directly contradicted by the data you have provided in Table 2. Your own summary shows that the French Energie Positive & Reduction Carbone standard utilizes a tiered system with four distinct energy levels and two carbon levels , and the Canadian Zero Carbon Building Standard offers two separate compliance routes (Design and Performance). Therefore, the generalization in the text that these new standards are strictly binary is a logical fallacy based on your own evidence. You must refine this argument—perhaps describing them as "threshold-based" rather than binary—to accurately reflect the nuance in the data.

3.The analysis persists in a category error by conflating voluntary guidance frameworks with tradable market certifications. By placing LETI and the RIBA 2030 Challenge in the same comparative matrix as LEED Zero and ILFI, you obscure the distinct economic functions of these instruments. LETI is a knowledge-sharing tool (public good) with no certification body, whereas LEED Zero is a market signaling asset (private good). The incentives for adoption are entirely different. To improve the rigor of the analysis, you should explicitly distinguish between Certifiable Standards and Voluntary Frameworks rather than treating them as fungible standards.

4.The discussion regarding the shift from design-based to performance-based verification  lacks a critical economic analysis of the risk transfer involved. You argue that this shift is a necessary response to the performance gap, which is technically accurate, but you fail to address the commercial reality of why a developer would accept this risk. A standard relying on post-occupancy data introduces significant liability for the developer regarding tenant behavior, unlike design-stage certifications. The conclusion and discussion sections would be significantly strengthened by moving beyond the environmental rationale to address the economic viability of this model. Without analyzing this risk asymmetry, the implicit assumption that the market will naturally migrate to these stricter standards is unsubstantiated.

5.Regarding the actionable recommendations requested in the previous review, the added points in the Conclusion  are a step in the right direction but remain somewhat generic. Specifically, the recommendation for “Improved transparency... reconciling the bottom-up approach with the top-down approach” is vague. Given your findings on the proliferation of disparate standards, a more high-value recommendation would address the need for interoperability or equivalence agreements between these regional standards to prevent market fragmentation for international real estate portfolios.

Author Response

Review 1
You are to be commended for the effort put into addressing the previous round of comments, particularly regarding the inclusion of carbon offset critiques and the clarification of regional contexts within the tables. The manuscript has improved in its coverage of the grey literature and now offers a more complete inventory of the current landscape. However, while the descriptive breadth is sufficient, the analytical depth and logical consistency remain problematic. My comments below are intended to help strengthen the paper’s contribution by addressing several critical areas where the argumentation is still disconnected from the empirical evidence presented, and where the response to the previous call for a “comparative framework” feels superficial.
1.While you have attempted to address the previous feedback regarding the descriptive nature of the paper by introducing a “comparative policy analysis” methodology section, there remains a significant gap between this stated framework and the actual analysis performed. You cite Mayer et al.’s framework to “clarify values and arguments,” yet the subsequent analysis in Sections 5 and 6 remains a technical list of metrics (e.g., energy use intensity, offset allowability) rather than an investigation into the institutional values or political dynamics that shaped them. For instance, the paper fails to explain why the UK context favored a voluntary professional coalition model like LETI , whereas the French context produced a state-aligned experimental framework like E+C-. Merely citing a policy analysis framework without applying it to explain these divergences renders the methodology section decorative rather than functional.
Thank you for your constructive and very helpful comments.
The manuscript addresses the broad topic of environmental building standards and frameworks and their evolution (pre and post Paris agreement). It identifies a new trend towards more streamlined and performance-based metrics that should be verified based on actual building performance. It identifies several drivers for this trend delving into the shortcomings and practical issues experienced in implementing EBS over the past 35 years across the globe. In doing so, we have clarified values (e.g. imperatives of addressing the climate emergency, the corporate style checklist approach adopted in earlier EBS vs the emerging performance-based discourse that is arguably better aligned with climate crisis imperatives ) and arguments (e.g., how to narrow the problem of the performance gap, necessity of an integrated approach to greenhouse gas emissions that goes beyond operational carbon, pros and cons of carbon offsetting etc).
We have explained how these non-regulatory standards and frameworks were developed over the past few years as the minimum regulatory requirements were not sufficient to achieve the level of performance required in the context of climate emergency. This is now extended to address the specific and very valid point raised above about the impact of institutional values and political dynamics in shaping these standards:
“This paper explains how the Paris Agreement and perceived failing in current standards and regulations have prompted a response to develop NZGHGEBS by various organisations around the world. It is the gap between regulatory codes and aspirations by sections of the construction industry and property owners and investors which has created a space for private organisations and coalitions of actors to develop frameworks and standards and methodologies for identifying zero GHG buildings. These standards exist in a space created by a lack of government legislation and, indeed, these standards might become obsolete if robust regulations were introduced in many countries. They can, however, inform the development of such regulations. Regional and contextual factors, including political dynamics, play a major role in how these frameworks and standards are developed. These sometimes serve as precursors to future mandatory environmental regulations, as demonstrated by the Energie Positive & Réduction Carbone (E+C−) framework in France. Conversely, in contexts where political support is insufficient—at least in the short term—to implement compulsory performance targets, an initial net zero framework may instead guide the development of a broader voluntary industry standard. The LETI framework, for example, illustrates how a grassroots initiative led by practitioners mobilised multiple professional bodies and private-sector organisations to produce the first Net Zero Carbon Buildings standard in the UK.”
2.The central argument that Net-Zero GHG Emission Building Standards (NZGHGEBS) are characterized by a “binary pass or fail approach” is factually incorrect and directly contradicted by the data you have provided in Table 2. Your own summary shows that the French Energie Positive & Reduction Carbone standard utilizes a tiered system with four distinct energy levels and two carbon levels , and the Canadian Zero Carbon Building Standard offers two separate compliance routes (Design and Performance). Therefore, the generalization in the text that these new standards are strictly binary is a logical fallacy based on your own evidence. You must refine this argument—perhaps describing them as "threshold-based" rather than binary—to accurately reflect the nuance in the data.
Thank you for this important comment. We completely agree with you. The intent was to highlight a departure from a multi criteria/level system of assessment predominantly based on design/modelled performance. We have now revised the manuscript and have replaced ‘binary pass or fail approach’ with ‘threshold-based approach’ based on few clearly defined performance metrics.
3.The analysis persists in a category error by conflating voluntary guidance frameworks with tradable market certifications. By placing LETI and the RIBA 2030 Challenge in the same comparative matrix as LEED Zero and ILFI, you obscure the distinct economic functions of these instruments. LETI is a knowledge-sharing tool (public good) with no certification body, whereas LEED Zero is a market signalling asset (private good). The incentives for adoption are entirely different. To improve the rigor of the analysis, you should explicitly distinguish between Certifiable Standards and Voluntary Frameworks rather than treating them as fungible standards.
Thanks for this helpful comment. We had included these frameworks in Table 2 before, as these were instrumental in developing the Net Zero Carbon Buildings standard in the UK (please see the explanation in our response to the first comment). However, we agree with your comment above and therefore have now removed the reference to LETI and RIBA 2030 Climate Challenge from Table 2 to avoid any misunderstanding (they are still covered in the text of the manuscript as important ‘frameworks’ distinguished from standards and certification schemes).
4.The discussion regarding the shift from design-based to performance-based verification lacks a critical economic analysis of the risk transfer involved. You argue that this shift is a necessary response to the performance gap, which is technically accurate, but you fail to address the commercial reality of why a developer would accept this risk. A standard relying on post-occupancy data introduces significant liability for the developer regarding tenant behavior, unlike design-stage certifications. The conclusion and discussion sections would be significantly strengthened by moving beyond the environmental rationale to address the economic viability of this model. Without analyzing this risk asymmetry, the implicit assumption that the market will naturally migrate to these stricter standards is unsubstantiated.
We acknowledge this as a potential barrier. However, the paper aims to highlight the growing trend to recognise that, to achieve tangible and verifiable environmental benefits, stakeholders need to work collaboratively and share the responsibility. There are contractual arrangements that could facilitate such collaboration such as green lease agreements and performance contracts. This was, to some extent, covered in the manuscript and is now extended in the revised manuscript to address this important comment (Section 7: Discussion):
“The use of a performance-based assessment has the potential to be an important development in the delivery of net zero GHG emission accredited building because it suggests that the burden of compliance will be shared between the design team and building operators. In the case of the buildings with tenants, whether they are residential or commercial, this suggests that closer collaboration will be required for the targets to be met. This is because the conditions that will facilitate compliance will be established by the design and delivery team. However, ensuring compliance will be the responsibility of facilities managers and/or building operators. In some cases, legal instruments, such as green leases, are likely to be used to support tenant compliance with operational energy targets. Performance contracts, on the other hand, can be used to ensure sufficient and proactive aftercare from the construction teams to achieve performance targets. Whilst this shared responsibility creates uncertainty, it is arguably a more accurate reflection of the roles of the various parties (i.e. designers, builders, and users) in delivering building performance. In addition, literature on the psychology of goal and target setting highlights the benefit of having a small number of targets which require a collective effort, as characterized by NZGHGEBS, for achieving behaviour change [126]. However, it should be noted that these changes will not happen without a robust business case that aligns environmental outcomes with financial return for stakeholders. Owner-occupiers have a strong incentive to achieve performance targets in practice and will benefit from lower utility bills and operational costs. However, developers may not necessarily see the value of opting for stricter requirements unless they can achieve price premiums for their higher rated buildings or can benefit from the social and reputational value of following the best practice”.
5.Regarding the actionable recommendations requested in the previous review, the added points in the Conclusion are a step in the right direction but remain somewhat generic. Specifically, the recommendation for “Improved transparency... reconciling the bottom-up approach with the top-down approach” is vague. Given your findings on the proliferation of disparate standards, a more high-value recommendation would address the need for interoperability or equivalence agreements between these regional standards to prevent market fragmentation for international real estate portfolios.
We have revised the key requirements/actions listed in the Conclusion section of the paper, directly incorporating your valuable suggestion as an action and adding clarification for the bottom-up and top-down methods as transparency and equivalency between these methods and how net-zero targets are derived is also necessary (highlights show the new amendments):
“The review presented in this paper points to the following key requirements that can help maximize the benefits of the new generation of environmental building standards:
• Improved transparency in how the benchmarks and targets are derived, reconciling the bottom-up (best-practice building performance) approach with the top-down (GHG-based budget) approach (see Figure 6)
• Contractual arrangements to facilitate building fine tuning after completion and post-occupancy evaluations (including post-construction LCA audits to cover both operational and embodied carbon)
• Robust measurement and verification protocols to demonstrate the effectiveness of these standards in practice, using third party independent verification
• Address interoperability or equivalence agreements between regional standards to prevent market fragmentation, especially for international real estate portfolios.”

Reviewer 2 Report

Comments and Suggestions for Authors

I appreciate the thoughtful revisions made in response to the previous feedback. The paper now reads more fluently, presents a clearer structure, and introduces a helpful taxonomy that strengthens the overall contribution.

That said, I recommend minor revisions to further strengthen the contribution.

1. Analytical Depth: The taxonomy figure is helpful, but its analytical value would improve if accompanied by a brief evaluative comparison, such as a scorecard or matrix, highlighting how different standards perform across key dimensions (scope, rigor, offset strategy, verification mechanisms).

2. Practical Examples: Including one or two real-world examples (even brief) of how selected NZGGEBS are implemented in actual projects would help ground the review in practice.

3. Visual Simplification: Figure 1 can be refined to improve readability, consider simplifying the layout or using comparative visuals to better convey differences among standards.

4. Similarity Statement: Please include a short note in the manuscript confirming the similarity report outcome (“iThenticate similarity score of 22%, with individual overlaps <1%”) and affirming originality.

5. Language Polishing: The language is mostly clear, but a final round of light editing is recommended to remove minor redundancies and improve flow in some sections.

With these revisions, I believe the paper will make a valuable contribution to the literature on environmental building standards and net-zero performance frameworks.

Thank you.

Comments on the Quality of English Language

A final round of light editing is recommended.

Author Response

Review 2
I appreciate the thoughtful revisions made in response to the previous feedback. The paper now reads more fluently, presents a clearer structure, and introduces a helpful taxonomy that strengthens the overall contribution.
That said, I recommend minor revisions to further strengthen the contribution.
Thank you very much for your helpful and constructive comments.
1.
Analytical Depth: The taxonomy figure is helpful, but its analytical value would improve if accompanied by a brief evaluative comparison, such as a scorecard or matrix, highlighting how different standards perform across key dimensions (scope, rigor, offset strategy, verification mechanisms).
The new Figure 1 is inserted in the Introduction section to provide a timeline for the introduction of the most used environmental building standards (EBS). We have now updated this figure for further clarity and legibility and have also referred to Tables 1 & 2 that provide further contextual information in a matrix format in the Figure’s legend. We have also made revisions in the tables to clarify where information about the scope, offset strategy, and verification mechanism can be found. We did not include a subjective assessment of the rigor of each individual EBS in these tables, although this is generally discussed in the paper in the context of transition from pre-2015 EBS to the new EBS that have introduced performance-based metrics verified based on actual performance.
2.
Practical Examples: Including one or two real-world examples (even brief) of how selected NZGGEBS are implemented in actual projects would help ground the review in practice.
The first revision of the manuscript cited a reference related to this:
Oreskovic, L.; Gupta, R.; Strong, D. In-use energy and carbon performance of a true zero carbon housing development in England, Science and Technology for the Built Environment, (2021) 27, 1425–1439.
We have now added a new paragraph that provides more examples based on the Australian and UK versions of the NABERS scheme:
“The introduction of the NABERS UK scheme, following the success of the original Australian scheme, is an example of how the new wave of EBS are being used in the construction industry as a voluntary measure to demonstrate buildings’ sustainability credentials. There are several examples of NABERS 5-6 Star rated buildings in Australia achieving energy use intensities close to 30 kWh/m² per annum in the commercial office sector [127]. The highest UK NABERS rating for the base-building of commercial offices (the space and services managed by the Landlord), at the time of writing this article, is 5-Star according to CIBSE, the respective accreditation body [128]. This is commensurate with the RIBA 2030 Climate Challenge interim target set out for 2025.”
The references provided in the above citations will introduce readers to real-world case studies:
127. WBCSD, 2023. Net-zero operational carbon buildings state of the art, World Business Council for Sustainable Development, <https://www.arup.com/globalassets/downloads/insights/net-zero-opertationa-buildings-state-of-the-art.pdf> (accessed December 4, 2025). 128. CIBSE, 2025. Leading the way: First UK Building achieves NABERS UK 5-Star energy rating following Design for Performance Journey, The Chartered Institution of Building Services Engineers, < https://www.cibse.org/policy-advocacy/news/leading-the-way-first-uk-building-achieves-nabers-uk-5-star-energy-rating-following-design-for-performance-journey/> (accessed December 4, 2025).
3.
Visual Simplification: Figure 1 can be refined to improve readability, consider simplifying the layout or using comparative visuals to better convey differences among standards.
We have updated Figure 1 to make it more legible for readers.
4.
Similarity Statement: Please include a short note in the manuscript confirming the similarity report outcome (“iThenticate similarity score of 22%, with individual overlaps <1%”) and affirming originality.
We have checked the final version of the manuscript using Turnitin (a similar tool for which we have a license) and confirmed this in the ‘Author Contributions’ part of the article as follows:
“Turnitin similarity score for this review article is 19%, with individual overlaps < 1%.”
In our experience, this similarity score is not unusual for ‘review’ papers that typically have similarity scores between 15-30%. We checked the text thoroughly. Some similarities are inevitable, for example, when we list the name of the criteria used in the standards. However, we confirm that this is an original review paper with very few individual overlaps.
5.
Language Polishing: The language is mostly clear, but a final round of light editing is recommended to remove minor redundancies and improve flow in some sections.
We have proofread and edited the text again for this submission taking on board your helpful suggestion.
With these revisions, I believe the paper will make a valuable contribution to the literature on environmental building standards and net-zero performance frameworks.

Reviewer 3 Report

Comments and Suggestions for Authors

The comments from the first round of review have been addressed. Figure 1 should be updated to be legible for readers.

Author Response

Review 3
The comments from the first round of review have been addressed. Figure 1 should be updated to be legible for readers.
Thank you very much for your very helpful and constructive comments in the first round. We have now updated Figure 1 to make it more legible for readers.

Round 3

Reviewer 1 Report

Comments and Suggestions for Authors

The third revision of the manuscript has matured significantly in its analytical precision. The shift in terminology from a "binary" to a "threshold-based" approach is a crucial improvement that finally aligns your theoretical argument with the empirical evidence of tiered standards presented in Table 2. Furthermore, the inclusion of a dedicated discussion on the economic mechanics of performance verification—specifically addressing the misalignment between developers and occupiers and the role of legal instruments like green leases —adds the necessary layer of management theory that was previously missing. This successfully contextualizes the risk transfer inherent in moving from design-stage to post-occupancy certification.

The distinction you have now drawn between frameworks acting as regulatory precursors (like France's E+C-) versus grassroots industry standards (like LETI)  is a strong addition that effectively utilizes the policy analysis framework. To fully capitalize on this, I suggest ensuring that the conclusion briefly reflects this finding when discussing future policy pathways, as it offers a more nuanced "theory of change" regarding how voluntary standards evolve into regulation compared to the earlier drafts.

Please conduct a final quality control check on your reference list to ensure all citations are complete and formatted according to the journal's standards. For instance, Reference 52 (UK Net Zero Carbon Standard)  appears to be an incomplete citation compared to the level of detail provided for other sources. Ensuring these details are finalized is the only remaining hurdle to publication.