Review Reports - Towards Climate-Just and Sustainable Schools: Developing the Level(s)+37 Passive Design Framework

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This article presents the Level(s)+37 Passive Design Framework, a comprehensive evaluation tool consisting of 37 indicators aimed at improving passive performance and advancing climate justice in primary and secondary schools. The framework is anchored in the six macro-objectives of the European Level(s) scheme and organized into seven thematic clusters, which address thermal comfort, indoor air quality, solar control, daylighting, environmental ergonomics, ecological sustainability, circular economy, climate justice, social equity, and the educational value of stakeholder engagement.

The research methodology followed a six-phase mixed-methods protocol. It began with a systematic literature review, followed by semi-structured interviews, a two-round Delphi survey, and the application of the Analytic Hierarchy Process (AHP) to weight the indicators. Strategic action lines were then derived using a TOWS-CAME matrix, culminating in the consolidation of the indicators with precise definitions and consideration of their lifecycle relevance.

The main objective of this framework is to guide the transition of Spanish school buildings toward healthier, low-impact environments by adapting and calibrating the European Level(s) system to local needs and characteristics. While the study demonstrates solid methodological rigor, the reviewer has concluded that the paper requires major revision before it can be accepted for publication.

Please respond carefully to each of the following questions to address the reviewer’s concerns and strengthen the paper:

Q1. Clearly highlight the originality of the framework and explain the gap in existing research and practice that this study addresses.
Q2. Define the specific knowledge gap the paper intends to close.
Q3. Since the framework was developed for primary and secondary schools in Spain, how do the authors envision its transferability to educational buildings in other climatic regions or regulatory contexts? What modifications would be necessary to ensure wider applicability?
Q4. The framework includes 37 indicators structured across seven thematic clusters. Please elaborate on how the Spanish context—particularly the large proportion of older school buildings designed before modern energy-efficiency standards—shaped the selection and weighting of these indicators.
Q5. The six-phase methodology engaged 170 experts through Delphi surveys and AHP. How did the authors ensure diversity across technical, pedagogical, research, and administrative profiles to guarantee balanced consensus and robust indicator weighting?
Q6. The article mentions pilot deployment in two Spanish schools and one Chilean school. Provide more details on the main results, challenges, and lessons from these pilots, and explain how they informed adjustments to the final version of the framework.
Q7. Beyond functioning as an evaluation tool, what mechanisms will allow the framework to influence real design and renovation practices in schools?
Q8. The study notes barriers such as limited technical training and the lack of clear metrics. How does the Level(s)+37 framework address these issues through its indicators, action lines, and implementation roadmap?
Q9. The framework emphasizes educational value and stakeholder participation. What strategies are recommended for embedding these indicators into the curriculum and engaging students, teachers, and facility managers in the process?
Q10. The framework is aligned with global agendas such as the SDGs and the New European Bauhaus. Which policy recommendations would the authors propose for national or regional governments to incentivize its adoption and integrate it into regulations or funding programs?
Q11. The paper states that the framework seeks to create sustainable, inclusive, and climate-resilient schools that also foster participatory governance. What long-term research plans are in place to assess the framework’s impact on these broader educational and social goals, beyond building performance metrics?
Q12. Please include a graphical representation of the research methods in Section 3 (Materials and Methods) to illustrate the six-phase protocol.

Author Response

The main objective of this framework is to guide the transition of Spanish school buildings toward healthier, low-impact environments by adapting and calibrating the European Level(s) system to local needs and characteristics. While the study demonstrates solid methodological rigor, the reviewer has concluded that the paper requires major revision before it can be accepted for publication.

We appreciate the reviewer’s thoughtful and constructive comments. In response, we have clarified the definitions and rationale of the 37 indicators, expanded the description of the mixed-methods approach (Delphi, AHP, and TOWS-CAME), and strengthened the link between methodological steps and strategic outcomes. The revised version also includes a clearer explanation of how climate justice, social equity, and life-cycle considerations are operationalized, along with enhanced validation through pilot case studies. Overall, the paper has been substantially revised to improve structure, clarity, and coherence, addressing all major concerns raised.

Please respond carefully to each of the following questions to address the reviewer’s concerns and strengthen the paper:

Q1. Clearly highlight the originality of the framework and explain the gap in existing research and practice that this study addresses.

We thank the reviewer for this valuable comment. In response, we have expanded the Introduction by adding a new paragraph under the subsection “Novelty and Research Gap.” This addition explicitly highlights the originality of the Level(s)+37 Passive Design Framework and clarifies the specific research gap it addresses. The revised text now explains that the framework extends the European Level(s) system through 37 new context-specific indicators tailored to Spanish primary and secondary schools, responding to their distinct climatic, architectural, and regulatory conditions. It also emphasizes that, unlike existing schemes such as Level(s), BREEAM-Education or DGNB, this proposal integrates passive design, climate justice, social equity, and educational value within a single evaluative structure. This strengthens the contribution of the paper by demonstrating how the framework fills the current gap in both research and practice: the lack of localized, holistic assessment tools capable of linking environmental performance with social inclusion, resilience, and educational transformation in school environments.

Q2. Define the specific knowledge gap the paper intends to close.

Although several European frameworks such as Level(s), BREEAM-Education, and DGNB evaluate the environmental performance of buildings, none provide an integrated and context-sensitive tool to assess schools in terms of passive design, climate justice, and educational value. In Spain, this gap is particularly significant due to the absence of standardized indicators adapted to its diverse climatic, architectural, and regulatory conditions. As a result, current methodologies fail to capture the social and pedagogical dimensions of sustainable school refurbishment. The Level(s)+37 Passive Design Framework addresses this gap by extending the European Level(s) system through 37 new context-specific indicators for Spanish primary and secondary schools. It establishes a holistic evaluation structure that connects environmental performance with social inclusion, resilience, and educational transformation, bridging the divide between research and practice in sustainable school design and renovation.

Q3. Since the framework was developed for primary and secondary schools in Spain, how do the authors envision its transferability to educational buildings in other climatic regions or regulatory contexts? What modifications would be necessary to ensure wider applicability?

The Level(s)+37 Passive Design Framework was conceived as a locally calibrated extension of the European Level(s) system; however, its structure and methodology are inherently adaptable. The framework’s modular design allows the 37 new indicators to be reweighted, substituted, or expanded according to different climatic zones, building typologies, and national regulations. Transferability can be achieved through three main actions: (1) recalibrating climatic and comfort thresholds using local meteorological data, (2) aligning regulatory indicators with regional energy codes and educational standards, and (3) contextualizing social and pedagogical dimensions according to cultural and institutional priorities. This flexibility enables the framework to serve as a reference model for Mediterranean, Latin American, or Global South contexts, promoting comparable assessments of environmental performance, social inclusion, and educational transformation across diverse educational building systems.

Q4. The framework includes 37 indicators structured across seven thematic clusters. Please elaborate on how the Spanish context—particularly the large proportion of older school buildings designed before modern energy-efficiency standards—shaped the selection and weighting of these indicators.

The Spanish school building stock strongly influenced both the selection and weighting of the 37 indicators. Over 80% of schools were built before the 2006 Technical Building Code (CTE), lacking adequate insulation, ventilation, and solar control. Consequently, priority was given to indicators addressing passive envelope performance, thermal inertia, and natural ventilation capacity. Additionally, the socio-climatic diversity of Spain—ranging from Mediterranean to continental and oceanic regions—required context-specific weighting based on climatic sensitivity. Regulatory obsolescence and social vulnerability were also key factors: indicators on indoor air quality, user comfort, and adaptive reuse were strengthened to reflect equity and resilience objectives. The resulting seven thematic clusters balance environmental performance with social and educational value, ensuring the framework responds to the distinctive physical, climatic, and regulatory conditions of the Spanish school stock while remaining compatible with the European Level(s) structure.

Q5. The six-phase methodology engaged 170 experts through Delphi surveys and AHP. How did the authors ensure diversity across technical, pedagogical, research, and administrative profiles to guarantee balanced consensus and robust indicator weighting?

Expert diversity was ensured through a structured, multi-sectoral selection process. Participants were identified from four complementary domains: (1) technical professionals in architecture, engineering, and energy retrofit (35%); (2) educational and pedagogical experts, including school principals and teachers (28%); (3) academic researchers in sustainability, environmental psychology, and building performance (25%); and (4) public administration and policy representatives involved in educational infrastructure planning (12%). Gender balance (54% women, 46% men) and regional representation across Spain’s five main climatic zones were also considered. This cross-disciplinary composition guaranteed plural perspectives in each Delphi round. Statistical validation using Kendall’s W coefficient (W = 0.71) confirmed strong inter-group agreement. The Analytic Hierarchy Process (AHP) then refined indicator weighting through pairwise comparison, ensuring proportional representation of environmental, social, and educational dimensions. Together, these measures strengthened the robustness, transparency, and replicability of the framework’s consensus-building process.

Q6. The article mentions pilot deployment in two Spanish schools and one Chilean school. Provide more details on the main results, challenges, and lessons from these pilots, and explain how they informed adjustments to the final version of the framework.

The pilot deployment in Spain and Chile served as an exploratory validation stage to confirm the operational feasibility and clarity of the Level(s)+37 indicators. Because the pilots were limited in duration and scale, the authors decided not to include detailed quantitative results in this paper. These case studies have instead informed a separate research line focused on the empirical evaluation and long-term monitoring of the framework under different climatic and institutional conditions, which will be reported in a subsequent publication.

Q7. Beyond functioning as an evaluation tool, what mechanisms will allow the framework to influence real design and renovation practices in schools?

The Level(s)+37 Framework is conceived not only as an assessment instrument but also as a decision-support tool to guide design and refurbishment processes in educational buildings. Its indicators have been structured to align with national and European policy instruments—such as the Spanish Long-Term Renovation Strategy (ERESEE), the National Energy and Climate Plan (PNIEC), and the EU Level(s) system—facilitating direct integration into public funding schemes and technical guidelines. Additionally, the framework promotes participatory assessment, engaging teachers, students, and local authorities in the design phase to strengthen the social and educational dimensions of renovation projects. Its modular structure enables use at different project stages, from preliminary diagnosis to post-occupancy evaluation, supporting continuous improvement cycles. In this way, the framework operates as a bridge between research, public policy, and professional practice, fostering tangible progress toward sustainable, inclusive, and climate-resilient school environments.

Q8. The study notes barriers such as limited technical training and the lack of clear metrics. How does the Level(s)+37 framework address these issues through its indicators, action lines, and implementation roadmap?

The Level(s)+37 Framework directly addresses these barriers by operationalising sustainability concepts into measurable, easy-to-apply indicators and by including an implementation roadmap focused on capacity building. First, each indicator is supported by simplified calculation methods, reference values, and data sources adapted to school environments, ensuring usability by non-experts. Second, the framework introduces “action lines” linking technical indicators to educational and managerial practices, promoting collaborative decision-making among teachers, architects, and administrators. Finally, the roadmap includes training modules for local authorities and school facility managers, designed to strengthen technical literacy and ensure consistent data collection across regions. Together, these elements translate abstract sustainability goals into actionable guidance, facilitating the adoption of passive design and holistic refurbishment practices even in schools with limited technical resources.

Q9. The framework emphasizes educational value and stakeholder participation. What strategies are recommended for embedding these indicators into the curriculum and engaging students, teachers, and facility managers in the process?

The Level(s)+37 Framework integrates educational value through participatory and experiential learning strategies that connect environmental assessment with daily school activities. Three main mechanisms are proposed. First, indicators related to indoor environmental quality, energy use, and resource circularity are translated into didactic tools—such as classroom monitoring dashboards, environmental audits, and student-led observation projects—linking data collection to STEM and citizenship education. Second, teacher training and co-design workshops foster collaboration between educators, architects, and facility managers, ensuring that sustainability principles inform both the curriculum and the school’s physical transformation. Third, the framework promotes “learning-by-doing” governance models, where students and staff jointly interpret results and propose improvement actions. These strategies embed sustainability competencies into the educational process, turning school buildings into living laboratories that strengthen ecological awareness, collective responsibility, and community participation.

Q10. The framework is aligned with global agendas such as the SDGs and the New European Bauhaus. Which policy recommendations would the authors propose for national or regional governments to incentivize its adoption and integrate it into regulations or funding programs?

To accelerate adoption, the authors recommend that national and regional governments integrate the Level(s)+37 Framework into existing renovation strategies and educational infrastructure programs. First, the framework could serve as a reference for evaluating projects funded under ERESEE, PNIEC, and Next Generation EU, ensuring coherence with SDGs 4, 7, 11, and 13 and the New European Bauhaus principles of sustainability, beauty, and inclusion. Second, regulatory incentives—such as additional scoring in public tenders or priority access to renovation grants—could be established for projects applying the framework. Third, regional education departments could adopt the indicators as part of their environmental management systems and curricular innovation plans, linking school refurbishment with pedagogical transformation. These policy measures would enhance cross-sector coordination and help mainstream passive design, social inclusion, and educational value in the sustainable renovation of schools.

Q11. The paper states that the framework seeks to create sustainable, inclusive, and climate-resilient schools that also foster participatory governance. What long-term research plans are in place to assess the framework’s impact on these broader educational and social goals, beyond building performance metrics?

Future research will focus on evaluating the Level(s)+37 Framework’s broader educational and social impacts through longitudinal and participatory studies. A multi-phase research plan is being developed to monitor pilot schools over a 3–5-year period, combining quantitative performance indicators with qualitative tools such as surveys, focus groups, and participatory observation. These instruments will assess outcomes related to students’ environmental awareness, teachers’ pedagogical innovation, and community involvement in school governance. Additionally, partnerships with regional education departments will facilitate integration of the framework into school self-evaluation systems, linking physical renovation to curricular and social transformation. This long-term approach aims to generate a robust evidence base demonstrating how sustainable building design can enhance inclusion, resilience, and participatory culture within educational environments.

Q12. Please include a graphical representation of the research methods in Section 3 (Materials and Methods) to illustrate the six-phase protocol.

Reviewer 2 Report

Comments and Suggestions for Authors

This paper presents a comprehensive and well-structured study that successfully develops the Passive Design Framework, a novel indicator system for assessing and promoting passive design, climate justice, and sustainability in school buildings. The research is highly relevant, addressing a critical gap at the intersection of architectural engineering, educational policy, and social equity. However, certain methodological details require further elaboration.

While the paper correctly identifies and describes the three core pillars, the logical connections between them and how they specifically and interactively inform the development of the individual Level(s)+37 indicators could be made more explicit.
The description of the semi-structured interviews and the Delphi survey would benefit from greater transparency. Providing the interview protocol (key questions), the selection criteria for the 170 experts, their specific disciplinary backgrounds, and geographic distribution is crucial for assessing potential biases.
Although the Consistency Ratio is acceptable, the paper does not detail the composition of the expert panel that performed the pairwise comparisons for the AHP. The validity of the resulting weights is highly dependent on the expertise and diversity of this group, and this information is essential for evaluating the objectivity and generalizability of the priority factors identified.
Metrics like "Community climate resilience" and "Building as a teaching aid" are conceptually valuable but lack a standardized measurement methodology. Without clear guidelines on how to quantify or qualitatively assess these, their application could lead to inconsistent results. The framework needs annexes or supplementary materials providing detailed assessment protocols for these softer metrics.
The study is firmly grounded in the Spanish and European context. A discussion on how the framework might need to be adapted for different climatic zones, economic contexts, or regulatory environments would greatly enhance its value and appeal to an international audience.
A robust conclusion should explicitly state the limitations of the current work.

Minor issue, the presentation of results, particularly Table 5, is overly dense and difficult to parse

Author Response

1. While the paper correctly identifies and describes the three core pillars, the logical connections between them and how they specifically and interactively inform the development of the individual Level(s)+37 indicators could be made more explicit.

We appreciate this insightful observation. In response, we have expanded the explanation of the three core pillars—environmental performance, social inclusion and climate justice, and educational and cultural value—to clarify their interconnections and how they collectively inform the development of the 37 indicators. A new paragraph has been added in Section 3.1 (“Conceptual Framework of the Level(s)+37 Model”), immediately after introducing the three pillars and before the methodological description

2. The description of the semi-structured interviews and the Delphi survey would benefit from greater transparency. Providing the interview protocol (key questions), the selection criteria for the 170 experts, their specific disciplinary backgrounds, and geographic distribution is crucial for assessing potential biases.

We appreciate this valuable suggestion. To enhance methodological transparency, we have expanded Section 3.2 (“Data Collection and Expert Consultation”) to include details on (a) the interview protocol and key questions, and (b) the expert selection process for the Delphi survey, specifying disciplinary profiles, gender balance, and geographic distribution.

3. Although the Consistency Ratio is acceptable, the paper does not detail the composition of the expert panel that performed the pairwise comparisons for the AHP. The validity of the resulting weights is highly dependent on the expertise and diversity of this group, and this information is essential for evaluating the objectivity and generalizability of the priority factors identified.

We appreciate this valuable comment. To address the reviewer’s concern, we have expanded the description of the AHP weighting process in Section Phase 4: Prioritisation via Analytic Hierarchy Process) to provide full transparency on the composition and characteristics of the expert panel that performed the pairwise comparisons.

The revised text now specifies the number of experts (48) who participated in the AHP stage, their disciplinary backgrounds, gender balance, and geographic distribution across Spain’s five climatic regions. This information clarifies how representativeness and methodological robustness were ensured.

4. Metrics like "Community climate resilience" and "Building as a teaching aid" are conceptually valuable but lack a standardized measurement methodology. Without clear guidelines on how to quantify or qualitatively assess these, their application could lead to inconsistent results. The framework needs annexes or supplementary materials providing detailed assessment protocols for these softer metrics.

We appreciate this constructive comment. We agree that qualitative indicators such as “Community climate resilience” and “Building as a teaching aid” require explicit methodological guidelines to ensure consistency and replicability. In response, Section Phase 6: Detailed Design of the Indicator System) has been substantially expanded to include detailed assessment protocols directly within the main text, rather than in supplementary materials.

5. The study is firmly grounded in the Spanish and European context. A discussion on how the framework might need to be adapted for different climatic zones, economic contexts, or regulatory environments would greatly enhance its value and appeal to an international audience.

We thank the reviewer for this valuable suggestion. We fully agree that the discussion of transferability is crucial to broaden the relevance of the Level(s)+37 Framework beyond the Spanish and European context. To address this point, a new paragraph has been added to the Discussion section (Section 5), elaborating on the framework’s adaptability to different climatic, socioeconomic, and regulatory conditions.

6. A robust conclusion should explicitly state the limitations of the current work.

We fully agree with the reviewer that explicitly acknowledging the study’s limitations enhances the transparency and robustness of the conclusions. Accordingly, a new paragraph has been added at the end of the Conclusions section, discussing the main methodological and contextual limitations of the research, as well as directions for future work.

Minor issue, the presentation of results, particularly Table 5, is overly dense and difficult to parse

We appreciate the reviewer’s observation regarding the density of Table 5. To improve readability and facilitate interpretation, Table 5 has been redesigned and reformatted. The updated version now:

Separates the seven thematic clusters of indicators into clearly defined sub-sections.
Highlights the indicator codes and key variables in bold, enabling faster reference.
Uses alternating shading and spacing between rows to visually differentiate indicator categories.
Includes a concise explanatory note below the table, summarizing the purpose of each cluster and guiding readers toward the corresponding discussion in Section 4.2.

These adjustments substantially improve the visual clarity and accessibility of the data, making the structure of the Level(s)+37 indicator system easier to follow.

Reviewer 3 Report

Comments and Suggestions for Authors

This study developed a passive design evaluation framework called "Level (s)+37", aimed at promoting the comprehensive performance improvement of primary and secondary school campus buildings in terms of environmental sustainability, climate adaptability, and social equity. The research question has significant practical significance and is highly aligned with international policy orientations such as the EU's Green Deal and Sustainable Development Goals. The paper adopts a mixed research method, with rigorous design, abundant data, in-depth analysis, and a scientific and systematic framework construction process. The research results have made significant contributions to fields such as building sustainability assessment and educational facility design. The main modification suggestions are as follows:
1) Please add a paragraph on 'research limitations' in the discussion section.
2) Although it was mentioned that pilot projects were conducted in two Spanish schools and one Chilean school, there is a lack of specific data support. Suggest displaying the pilot application results of some key indicators in the main text or supplementary materials.
3) There are a few long sentences and repetitive expressions (such as the abstract and Featured Application sections being almost identical). It is recommended to further streamline and differentiate to improve the conciseness of the writing.

Author Response

We sincerely thank the reviewer for the positive and encouraging evaluation of our work. We are pleased that the relevance, methodological rigor, and policy alignment of the study were recognized. In response to the constructive suggestions provided, we have revised the manuscript extensively to improve clarity, methodological transparency, and international applicability.
All reviewer comments have been carefully addressed, including the addition of new explanations in the Introduction, expanded methodological details in Section 3 (Materials and Methods), and clearer visual and structural improvements in Figures 3–4 and Table 5.
We believe these modifications further strengthen the scientific robustness and practical relevance of the Level(s)+37 Framework as a tool for sustainable, inclusive, and climate-resilient school design.

1) Please add a paragraph on 'research limitations' in the discussion section.

We appreciate the reviewer’s valuable suggestion. A new paragraph has been added at the end of the Discussion section to explicitly address the research limitations and outline future directions. This addition clarifies the scope of the study and reinforces its transparency and methodological rigor.

2) Although it was mentioned that pilot projects were conducted in two Spanish schools and one Chilean school, there is a lack of specific data support. Suggest displaying the pilot application results of some key indicators in the main text or supplementary materials.

We appreciate the reviewer’s insightful observation. The pilot applications of the Level(s)+37 Framework were conducted in two Andalusian schools (southern Spain) and one Chilean school (Santiago de Chile), selected to test the framework’s adaptability to different climatic, social, and regulatory contexts. These pilots primarily aimed to validate the clarity, feasibility, and cross-sector usability of the 37 indicators, rather than to generate statistically representative datasets.

As the quantitative monitoring and longitudinal data collection are still ongoing, detailed results are not yet included in this version of the paper. Instead, we have revised Section 4.3 (Pilot Application and Validation) to explicitly describe the scope, objectives, and methodological insights of the pilot studies, while clarifying that the full empirical results will be presented in a forthcoming publication focused on field validation and comparative analysis.

3) There are a few long sentences and repetitive expressions (such as the abstract and Featured Application sections being almost identical). It is recommended to further streamline and differentiate to improve the conciseness of the writing.

We appreciate the reviewer’s valuable observation regarding stylistic refinement. In the revised version, the Abstract and Featured Application sections have been restructured and differentiated to clarify their distinct purposes:

The Abstract now provides a concise overview of the research aim, methodology, and main outcomes.
The Featured Application section has been rewritten to highlight the practical implications of the Level(s)+37 Framework, particularly its capacity to guide decision-making and policy alignment in school retrofitting.

Additionally, the entire manuscript was carefully reviewed to reduce sentence length, eliminate redundancies, and enhance readability, ensuring greater clarity and conciseness while maintaining academic rigor.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

No further comments. All the reviewers’ questions and suggestions were well accepted by the authors, and the paper is now ready to be published.