The Nexus of Morphology and Sustainable Urban Form Parameters as a Common Basis for Evaluating Sustainability in Urban Forms

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The topic addressed by the authors is contemporary and important. The text itself is written in a clear and logical way.

The article is well organized – in the appropriate order, there is: abstract, introduction, methodology, results, discussion, conclusions. Unfortunately, there was no indication of Limitations of the study. The authors should add it after Conclusions.

The authors cited 60 references only. Although the references correspond with the topic, I feel that this number should be increased by about 15-20 items. This will give a stronger scientific basis and will help strengthen the discussion and conclusions.

The authors defined the aim of the study, the justification for undertaking the study and the research questions in a very precise and clear manner. 

I assess the research methods as appropriate for the research questions posed. The presentation of results is also appropriate, but sources should be indicated below tables and figures.

The authors used appropriate statistical tools and methods of analysis. The results were presented in a clear and accessible way for the average reader, while maintaining an appropriate scientific level, which is not always obvious in contemporary publications.

The conclusions follow directly from the presented results. However, the discussion can be enriched by expanding the number of References to include the 15-20 items I have proposed. Potential implications of the results are also indicated – recommendations for decision-makers.

This makes the study potentially useful in practice, which is a significant added value of the authors' efforts.

After taking into account the comments, I recommend the work for publication. 

Author Response

We are grateful to the reviewer for taking his/her time to review our work. Their comments have helped us to improve the paper. Changes to the original manuscript are given in Blue in the revised version. Detailed responses to the reviewer’ comments are provided in the following lines.

 

 

Comment 1: The topic addressed by the authors is contemporary and important. The text itself is written in a clear and logical way.

Thank you very much for your kind and encouraging comments.

Comment #2: The article is well organized – in the appropriate order, there is: abstract, introduction, methodology, results, discussion, conclusions. Unfortunately, there was no indication of Limitations of the study. The authors should add it after Conclusions ( ADDING limitations of the study in 4-5 lines).

Thank you for your comment. Accordingly, with respect to the insightful comment, the required revision has been made, and a concise paragraph outlining the limitations of the study has been added after the Conclusion section. This text is as follows and has been added to the updated version of the paper:

Limitations and Further Research

While the findings showed a broad consensus among the 32 participants whose responses were deemed complete and valid, the authors recognized that excluding three incomplete submissions could introduce a mild sample bias. It is possible that those incomplete questionnaires may have represented different viewpoints, potentially influencing the final assessment outcome. Furthermore, although the one-way ANOVA indicated that the existing 32 responses were sufficiently consistent for meaningful results, the authors acknowledge that a higher response rate or additional participants from a variety of professional backgrounds could strengthen the robustness of the conclusions. Future research should therefore consider recruiting a larger and more diverse sample, possibly expanding beyond local academic circles to include practitioners and stakeholders from multiple regions. Moreover, the city samples and expert panels in our study leaned strongly towards European and Mediterranean contexts. While the core concept of applying typo-morphological frameworks and sustainability indicators can be adapted to most urban settings, the specific weighting of indicators might vary in non-European or rapidly urbanizing regions, where climatic conditions, cultural factors, or policy frameworks differ considerably. To address this limitation, subsequent studies could include case studies from diverse geographic areas to ascertain how well the proposed methodology translates to different climates, cultural practices, and regulatory environments. Incorporating these contexts will help refine the weighting system further, ensuring that parameters such as social equity, liveliness, and local building materials reflect the conditions of each region. By expanding both the sample size and regional scope, the proposed framework can evolve into a more universally applicable tool for assessing and guiding sustainable urban design.

Comment #3: The authors cited 60 references only. Although the references correspond with the topic, I feel that this number should be increased by about 15-20 items. This will give a stronger scientific basis and will help strengthen the discussion and conclusions.

 

The authors agree with the comment of the Reviewer to add more references to enhance the scientific basis of the paper. To accomplish that, additional references have been incorporated throughout the manuscript in the relevant sections to enhance the discussion and scientific foundation. The references are as follows:

[47]   A. Kearns, R. Forrest, Social cohesion and multilevel urban governance, Urban Stud. 37 (2000) 995–1017. https://doi.org/10.1080/00420980050011208/ASSET/0F416221-7BDF-402A-B6F3-4F2FCB0DAF0A/ASSETS/00420980050011208.FP.PNG

[48]   D. McMillan, D. Chavis, Sense of community: A definition and theory, J. Community Psychol. 14 (1986) 6–23. https://doi.org/10.1002/1520-6629(198601)14:1<6::AID-JCOP2290140103>3.0.CO;2-I

[57]   Y.R. Jabareen, Sustainable urban forms: their typologies, models, and concepts, Journal of Planning Education and Research. 26 (2006) 38–52. https://doi.org/10.1177/0739456X05285119

[58]   P. Newman, Sustainability and cities: extending the metabolism model, Landscape and Urban Planning 44 (1999) 219–226. https://doi.org/10.1016/S0169-2046(99)00009-2

[59]   M. Nikoofam, A. Mobaraki, Assessment of quality of life in the urban environment; case study: Famagusta, N. Cyprus, Civil Engineering and Architecture. 8 (2020) 860–872. https://doi.org/10.13189/cea.2020.080513

[60]   N. Dempsey, G. Bramley, S. Power, C. Brown, The social dimension of sustainable development: defining urban social sustainability, Sustainable Development 19 (2011) 289–300. https://doi.org/10.1002/sd.417

[61]   S.M. Wheeler, Planning for metropolitan sustainability, Journal of Planning Education and Research. 20 (2000) 133–145. https://doi.org/10.1177/0739456X0002000201

[62]   K.C. Seto, B. Güneralp, L.R. Hutyra, Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools, Proceedings of the National Academy of Sciences 109 (2012) 16083–16088. https://doi.org/10.1073/pnas.1211658109

[63]   M. Pacione, Urban environmental quality and human wellbeing: a social geographical perspective, Landscape and Urban Planning 65 (2003) 19–30. https://doi.org/10.1016/S0169-2046(02)00234-7

[65]   J.M. Bhagwat; V.A.R.U.V.E.L. Devadas, Planning for a sustainable compact city: A way forward. WIT Trans. Ecol. Environ. (2020) Nov 25, 241,113–122

[66]   B. Hopwood; M. Mellor; G. O’Brien, Sustainable development: Mapping different approaches. Sustainable development, (2005), 13, 38–52. https://doi.org/10.1002/sd.244

[67]   R. Rahbarianyazd, Typo-morphological analysis as a method for physical revitalization: The case of Famagusta’s residential district, Proceedings of the International Conference of Contemporary Affairs in Architecture and Urbanism – ICCAUA 3 (2020) 264–276. https://doi.org/10.38027/N262020ICCAUA316381.

[68]   S. Marshall, An area structure approach to morphological representation and analysis, Urban Morphol. 19 (2015) 117–134. https://doi.org/10.51347/JUM.V19I2.4026

[69]   F. Dieleman, M. Wegener, Compact City and Urban Sprawl, Built environment. 30 (2004) 308–323. https://doi.org/10.2148/benv.30.4.308.57151

[70]   B. Mobaraki, H. Ma, J.A. Lozano Galant, J. Turmo, Structural Health Monitoring of 2D Plane Structures, Appl. Sci. 11 (2021) 2000. https://doi.org/10.3390/app11052000.

[71]   A. Delice, The Sampling Issues in Quantitative Research, Educ. Sci. THEORY Pract. (2002).

[72]   B. Mobaraki, M. Vaghefi, Effect of the soil type on the dynamic response of a tunnel under surface detonation, Combust. Explos. Shock Waves 52 (2016) 363–370. https://doi.org/10.1134/S0010508216030175.

[73]   Y. Ye, A. van Nes Nes, Quantitative Tools in Urban Morphology: Combining Space Syntax, Spacematrix and Mixed-Use Index in a GIS Framework, Urban Morphology 18 (2014) 97–118. https://doi.org/10.51347/jum.v18i2.3997

[74]   J.L. Dibble, Urban Morphometrics: Towards a Quantitative Science of Urban Form, PhD Thesis, University of Strathclyde, (2016). https://doi.org/10.48730/xjms-3j31

[77]   Aliyar, A.K., Major, M.D., Tannous, H.O., Al-Esmail, F.R.A., Urban form and real estate value in Msheireb Downtown Doha, Qatar, Journal of Contemporary Urban Affairs 7 (2023) 224–241. https://doi.org/10.25034/ijcua.2023.v7n1-15

[79]   E. Hosseinzadehfard, B. Mobaraki, Investigating concrete durability: The impact of natural pozzolan as a partial substitute for microsilica in concrete mixtures, Constr. Build. Mater. 419 (2024). https://doi.org/10.1016/j.conbuildmat.2024.135491.

 

Comment #4: The authors defined the aim of the study, the justification for undertaking the study and the research questions in a very precise and clear manner.

The authors appreciate the positive comment of the Reviewer.

Comment #5: I assess the research methods as appropriate for the research questions posed. The presentation of results is also appropriate, but sources should be indicated below tables and figures (Putting the missing references of linked to the tables and figures).

Thank you for your observation. The missing source references linked to the tables and figures have been added accordingly. The updated captions of the Tables and figures in the updated version of the paper are as follows:

Figure 1. Caniggia’s dual hierarchy of form, as applied at building and city scale [6].

Figure 2. Caniggia and Maffei’s schematic and urban morphology layers framework [10].

Figure 3. Parameters and the indicators of sustainable urban form (developed by the authors).

Figure 4. A Model of a morphological framework for sustainability assessment (developed by the authors).

Figure 5. Analysis of gathered dataset linked to the elements of material, structure, room, building, plot, street, and city (developed by the authors).

 

Table 1. Interpretation of Kropf’s taxonomy of built form (developed by the authors).

Table 2. A sample of the ‘Checklist’ for the evaluation of sustainability based on the relevance of the sustainable urban form parameters within typo-morphological hierarchical levels (developed by the authors). 

 

 

 

Comment #6: The authors used appropriate statistical tools and methods of analysis. The results were presented in a clear and accessible way for the average reader, while maintaining an appropriate scientific level, which is not always obvious in contemporary publications.

 

Thank you very much for your encouraging feedback. We really appreciate it.

 

Comment #7: The conclusions follow directly from the presented results. However, the discussion can be enriched by expanding the number of References to include the 15-20 items I have proposed. Potential implications of the results are also indicated – recommendations for decision-makers. This makes the study potentially useful in practice, which is a significant added value of the authors' efforts (add 10 references in each chapter 2, literature review and 3, analysis of data).

 

Regarding the comments coming from the respected Reviewer, the stated helpful comment has been considered by adding the related references to the mentioned text. Accordingly, we have addressed this by adding approximately 15 relevant references in both the Literature Review (Section 2) and the Representative instance section (Section 3), as suggested.

Reviewer 2 Report

Comments and Suggestions for Authors

Topic interesting. The study develops in satisfying ways. The sections related to research questions, hyphoteses, presentation of results and discussion could be better elucidated and clearly explained. Further developments are due and required with regards to social, corporate, organisational and managerial implications.

Comments on the Quality of English Language

Professional English proofreading is to realized to improve the quality of manuscript

Author Response

We are grateful to the reviewer for taking his/her time to review our work. Their comments have helped us to improve the paper. Changes to the original manuscript are given in Blue in the revised version. Detailed responses to the reviewer’ comments are provided in the following lines.

 

 

Comment 1: Topic interesting. The study develops in satisfying ways. The sections related to research questions, hyphoteses, presentation of results and discussion could be better elucidated and clearly explained. Further developments are due and required with regards to social, corporate, organisational and managerial implications.

 

Thank you for Reviewer 3 insightful comments regarding our manuscript. Below is our response clarifying how we have addressed each of Reviewer 3 main points:

1. Clarification on Research Questions: (Reviewer 3 comment 1) We have expanded the explanation of our research questions to clarify why and how urban morphological scales (from material to city) influence sustainability parameters (efficiency, integrity, responsibility, acceptability, liveliness, and equity). This enriched description explicitly outlines our reasoning for examining both micro‐ and macro‐levels of urban form, thus providing a clearer framework for investigating the interplay between built elements and sustainability outcomes.
2. Clarification on Hypotheses: (Reviewer 3 comment 2) In the revised version, we detail the core hypothesis that each morphological layer exerts a distinct but interconnected effect on a set of sustainability indicators. By integrating more comprehensive statistical evidence (including ANOVA results and regression analyses), we demonstrate how particular parameters notably efficiency and acceptability tend to be consistently more influential across the varying scales of urban form. This elucidation makes our research design more transparent and strengthens the link between our research objectives and the findings.
3. Presentation of Results: (Reviewer 3 comment 3) We have sharpened our presentation of the results to make it clearer and more concise. Numerical findings and visual aids (e.g., score distributions, explanatory tables) have been refined to illustrate the significance and relevance of each sustainability parameter at different morphological scales. This approach enables readers to understand quickly how and why certain parameters, such as efficiency or integrity, receive higher ratings or demonstrate stronger correlations with specific layers of urban form.
4. Discussion: (Reviewer 3 comment 4) The revised discussion section now links our empirical findings more firmly to the underlying theoretical frameworks of urban morphology, as well as to broader sustainability principles. We elaborate on how the strongest correlations in our study can inform practical decision‐making, such as refining design strategies at the building or neighbourhood level. By embedding these findings within existing literature, we provide readers a coherent view of why these results matter for shaping sustainable urban environments.
5. Further Developments (Social, Corporate, Organisational, and Managerial Implications): (Reviewer 3 comment 5) Finally, we provide new content detailing how the model can be adapted for wider applications. In social terms, the analysis can guide community engagement efforts, highlighting ways to foster inclusivity and strong sense of place. For corporate, organisational, and managerial contexts, we clarify how developers, firms, and policymakers might use our morphological framework to optimise resource allocation, improve operational efficiency, and support equitable access to amenities. This reflection underscores the model’s versatility and its relevance to a diverse range of stakeholders.

Therefore, the final paragraph of the chapter 1 has been changed from:

To answer these questions, we have developed a coherent morphological framework for assessing sustainability, which synthesizes ideas from Conzen’s and Caniggia and Maffei’s taxonomies and integrates them with sustainable urban form parameters identified in the literature. We tested this framework through surveys and statistical analyses (see Section 3), then validated the consistency of the findings using ANOVA tests (see Section 4).

to:

To clarify these questions further, our aim is to examine the interplay between micro‐scale elements (e.g., construction materials, building layouts) and macro‐scale components (e.g., street networks, neighbourhood patterns) in determining overall sustainability. By aligning these morphology layers with well‐established sustainability parameters (including efficiency, integrity, responsibility, acceptability, liveliness, and equity), the research endeavours to reveal how each typological element of an urban area can either enhance or diminish its long‐term viability. This perspective ensures that researchers and practitioners can pinpoint precisely which urban‐form scale most strongly impacts sustainability goals, thereby answering the questions of ‘how’ and ‘to what extent.’

To answer these questions, we have developed a coherent morphological framework for assessing sustainability, which synthesises ideas from Conzen’s and Caniggia and Maffei’s taxonomies and integrates them with sustainable urban form parameters identified in the literature. We tested this framework through surveys and statistical analyses (see Section 3), then validated the consistency of the findings using ANOVA tests (see Section 4).

After collecting expert assessments across multiple scales, the study computed numerical scores to highlight which morphological elements (for example, plot, building, and city) scored highest in relevance to sustainability criteria. the study then presented subsequent statistical tests (such as ANOVA) in tables and figures to clarify the significance of these scores and verify that the panellists’ evaluations were broadly consistent. For further clarity, we also included visual representations such as plots showing the distribution of expert scores so that readers can discern how certain parameters (like acceptability and efficiency) consistently emerged as leading factors. By combining descriptive statistics with inferential testing, the results section underscores not simply the raw numerical findings but also the broader patterns that tie morphological characteristics to sustainability goals.

 

 

 

In addition, the following explanation has been added to the end of Chapter 3.1 “Methodology”:

The study’s hypotheses focus on the assumption that a strong correlation exists between hierarchical morphological units (e.g., from material to city scale) and measurable indicators of sustainability (e.g., resource efficiency, social interaction, equitable access). Specifically, our central hypothesis is that each morphological level exerts a distinct but interconnected influence on sustainability outcomes, such that higher‐level systems (like street networks or entire city districts) magnify or moderate the effects originating from lower levels (such as building materials or interior configurations). By statistically testing expert evaluations (through methods including descriptive analyses, ANOVA, and regression models), the study hypothesised that certain parameters particularly efficiency and acceptability would emerge as more impactful in shaping a robust, sustainable urban environment. The results confirmed and refined this initial assumption by demonstrating how morphological scales interact differentially with key sustainability parameters.

Moreover, the following paragraphs have been added to the end of Section 4, in the updated version of the paper:

Overall, the findings reveal that the parameters such as acceptability and efficiency hold particularly strong relationships with morphological layers across diverse scales, thereby suggesting targeted strategies ranging from improved building materials at the micro‐scale to enhanced public transport options at the macro‐scale. The discussion interprets these statistically significant results by connecting them to earlier scholarships on typological analysis and by highlighting the real‐world relevance for urban designers, planners, and policymakers. The intention is to demonstrate how the study’s approach can serve not merely as a diagnostic tool but as a roadmap for prioritizing sustainability interventions at the appropriate level of urban form

Looking ahead, the model’s integration of typo‐morphology with sustainability parameters can be broadened to encompass a range of social and organizational dimensions. For instance, at a social level, these findings can inform community‐engagement processes by identifying which physical elements best foster cohesion, safety, and a sense of place. In corporate and managerial contexts, firms could apply the model to gauge the long‐term operational viability of proposed developments, ensuring that efficiency measures, resource stewardship, and equitable access align with organizational goals. Similarly, public institutions could refine governance and policy frameworks, using the study’s evidence to draft planning guidelines that encourage morphological patterns conducive to sustainable growth. Ultimately, future research could expand the methodological toolkit (e.g., adding life‐cycle cost analyses or stakeholder surveys) to capture the financial and managerial implications of design decisions, thereby enhancing the model’s value for both private and public sector stakeholders.

 

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

This paper focuses on morphology and sustainable urban form parameters. Although the authors made some experiments and obtained some results, it  lacks innovation. Meanwhile, the article is not well presented or organized.

1.Literature review is poorly organized and lacks clarity in its logical flow, which should be restructured.

2.The authors do not explain the Methodology in detail, especially Figure 4 "the morphological framework". No merits can be found.

3.Figure 5, the subgraphs' numbers are not well labeled. Besides, R-square equals to 0.1431, and 0.1283, which are not significant.

Author Response

We are grateful to the reviewer for taking his/her time to review our work. Their comments have helped us to improve the paper. Changes to the original manuscript are given in Red in the revised version. Detailed responses to the reviewer’ comments are provided in the following lines:

 

Comment #1 This paper focuses on morphology and sustainable urban form parameters. Although the authors made some experiments and obtained some results, it lacks innovation. Meanwhile, the article is not well presented or organized.

The authors agree that in the old version of the paper the innovation of the study was not well explained.

In fact, the novelty of this paper lies in its development of a comprehensive, theoretically grounded model that integrates typo-morphological classification with the parameters of sustainable urban form, thereby offering an innovative framework for evaluating urban sustainability. By synthesizing Conzen’s, Caniggia’s, and Maffei’s framework of typo-morphological layers with Kropf’s hierarchy of built form and aligning this structure with clearly defined sustainable urban form parameters, the study derives a methodologically rigorous approach that bridges theoretical urban design with practical assessment tools. Furthermore, the integration of hierarchical morphological layers, assessed through empirical analysis with input from academics and urban professionals using statistical techniques, ANOVA, adds further depth and validation to the model. This methodological framework represents a significant advancement in the field, offering a robust framework for assessing sustainability across multiple urban scales, from material to city level.

Moreover, this study lies in its structured three-stage approach, integrating urban morphology and sustainable urban form through a comprehensive methodological framework. In the first stage, the study introduces key urban morphology approaches, particularly the typo-morphological perspective and develops a classification framework grounded in scale hierarchy theory, serving as the input phase. The second stage addresses the concept of sustainable urban form parameters, contributing analytical tools to assess built environment from a sustainability perspective when considering the morphology of a city. Finally, the third stage synthesizes these findings through an integrated methodology, enabling the development and evaluation of a toolkit that reveals for the evaluation of sustainability based on the relevance of the sustainable urban form parameters within typo-morphological hierarchical levels, constituting the output phase of the research.

To address this issue, the following paragraph has been added to the end of section 1, in the updated version of the paper:

 

 

 

 

 

 

The novelty of this paper lies in its development of a comprehensive, theoretically grounded model that integrates typo-morphological classification with the parameters of sustainable urban form, thereby offering an innovative framework for evaluating urban sustainability. By synthesizing Conzen’s, Caniggia’s, and Maffei’s framework of typo-morphological layers with Kropf’s hierarchy of built form and aligning this structure with clearly defined sustainable urban form parameters, the study derives a methodologically rigorous approach that bridges theoretical urban design with practical assessment tools. Furthermore, the integration of hierarchical morphological layers, assessed through empirical analysis with input from academics and urban professionals using statistical techniques, ANOVA, adds further depth and validation to the model. This methodological framework represents a significant advancement in the field, offering a robust framework for assessing sustainability across multiple urban scales, from material to city level.

 

 

The second part of the comment, concerning the presentation of the paper, will be explained and addressed in the response to Comment 2.

 

Comment #2: Literature review is poorly organized and lacks clarity in its logical flow, which should be restructured.

 

The authors agree that the old version of the paper requires some modifications linked to the order of presentation and clarity in some parts. To address these problems, Chapter 2 “Literature review” has been rewritten and the associated sections “2.1. Urban morphology”, “2.3. Classification and basic units of typo-morphological description”, “2.4. Sustainable urban form and its parameters”, “2.4.1 Efficiency”, “2.4.5 Liveliness”, “2.4.6 Equity”, and “Analytical tools”. The modified versions of these sections are as follows:

 

2.3. Classification and basic units of typo-morphological description

The research presented [22] identified three key themes crucial to a robust research agenda in urban morphology: establishing connections between structure and process, defining the fundamental units of morphological characterization, and delineating spatial relationships consistent with the implicit geometry of the urban area. Consequently, the development of a classification framework for the fundamental units in morphological description stands out as a paramount factor in urban morphology. This involves an understanding of the physical scales at which the urban area can be assessed.

The work of the Italian school of urban morphology, particularly by Caniggia and Maffei, introduces two perspectives on urban morphology: temporal and spatial. This is also known as co-presence or derivation, wherein the urban area takes shape on multiple scales simultaneously while being subject to change over time, crystallizing its form based on past events [23]. Caniggia's conception of the city relies on the fitting of objects (materials, rooms, buildings) into each other at various scales, employing a modular principle where understanding any scale necessitates comprehension of the scales below and above [24]. Accordingly, he devised a hierarchical concept for the urban area comprising four levels: elements, structures, systems, and organisms [10,20]. These four scales are explained as buildings, groups of buildings, the city, and a region [6]. Caniggia's spatial arrangement is based on elements, element structures, structures systems, and systems organisms. As shown in the Figure 1, this hierarchy is independently applied to buildings and towns, and the object of the smallest scale depends on the scale of the study area.

 

 

 

2.4. Sustainable urban form and its parameters

A sustainable urban area is perceived as a region that achieves enduring physical, social, and economic development while maintaining continuous access to natural resources within sustainable limits and ensuring ongoing resilience against environmental threats [28]. Various theoretical models have been proposed to conceptualize sustainable urban areas: (1) compact, high-density urban form [29], (2) low-density decentralized urban areas [30], (3) decentralized concentration, and (4) models influenced by Howard’s Garden City [31]. In each approach, the core is a balance of environmental, social, and economic factors [32].

From a broader review, six fundamental parameters efficiency, integrity, responsibility, acceptability, liveliness, and equity are identified as primary contributors to a sustainable urban form [33-35]. Briefly:

-Efficiency: Optimizes energy consumption in buildings and transportation systems [33-36, 37-39].

-Integrity: Maintains compositional and historical coherence, preserving social and visual harmony [33,40-44].

-Responsibility: Safeguards resources, lowers pollution, and integrates advanced technologies to minimize environmental impact [45,46].

-Acceptability: Improves quality of life by ensuring social interaction, sense of place, safety, and overall satisfaction [47-54].

-Liveliness: Encompasses ecological diversity, social interaction, and vibrancy in the urban environment [55-60].

-Equity: Addresses access to resources, affordability, and job opportunities [7,57, 60-66].

Within this study, these parameters serve as the main criteria for evaluating sustainability via the typo-morphological framework described earlier. In the following sections (3 and 4), we illustrate how each parameter interacts with a particular morphological layer ranging from material to city and provide a statistical validation of the approach.

 

2.4.1 Efficiency

Efficiency involves optimizing energy consumption, whether through building retrofitting or transportation systems [36], [37]. It is a crucial parameter widely discussed by researchers, forming a significant aspect of the sustainable urban form discourse [35], [38]. Energy efficiency in various urban forms has been extensively examined in different research studies [39], [33], [35]. The building sector and transportation are identified as primary contributors to energy consumption. Energy consumption in the building sector occurs through two distinct paths: energy capital, involving energy used in constructing buildings and infrastructure in urban areas, and energy revenue, which refers to energy consumed during a building's lifespan [37]. Consequently, this study delves into the critical factors influencing the efficiency of urban form, including building materials and design, transportation systems, and maintenance of the built environment.

2.4.5 Liveliness

Lynch identifies liveliness as one of the seven pillars determining a city's quality. He posits that the fundamental elements of functional liveliness encompass survival, safety, and compatibility [55,57]. Liveliness establishes a connection between ecology and society by exploring the relationship between inhabitants and their environment, emphasizing diversity and interactions [56,59]. On the ecological level, liveliness relates to design variety, incorporating changes, a sense of place, architectural distinctions, street lighting quality, security levels, and the eco-friendliness of the urban environment. The social dimension involves the interaction of individuals within the community, contributing to the vitality of the surroundings through the activities of people in that environment [55,60].

 

2.4.6 Equity

Equity is understood as the fare distribution of resources, fair access to basic needs and services, and finally, inclusive participation [7,61-63]. Equity deals with the essential Local services such as supermarkets, schools and health centers; leisure opportunities, open spaces; public transport; employment opportunities; affordable residency [60-66]. Rapid urbanization has, however, exceeded the capacity of the countries to provide sufficient infrastructure, while increased job insecurity in cities leads to further rises in social and economic inequities [7,59,62,65,66]. The big burden of the recent global economic downturn has contributed to unemployment and work losses, contributing in turn to reduced healthcare and increased social problems. Figure 3, shows the parameters of sustainable urban form with their indicators as obtained based on the literature review. The parameters of sustainable urban form are categorized according to the environmental, social, and economic characteristics within the scope of this study. These parameters serve as the primary overarching objectives for assessing sustainability in the urban area, utilizing the typo-morphology classification for urban form. The structure of any classification system outlines the purpose of the classification, encompassing its fundamental elements of description. Various frameworks exist for describing and classifying urban forms [57,64]. The methodology employed in this study, as illustrated by a representative example in the subsequent section, is centered on the classification and correlation of parameters and rules of sustainable urban forms with the framework of morphological layers.

 

3.2 Analytical tools

A methodology was devised to evaluate the integration of various indicators pertinent to sustainable urban form parameters with typo-morphological elements, grounded in a classification framework spanning multiple scales including the city level [49,67-69]. In accordance with this framework, a checklist was prepared using the proposed indicators. To validate the coherence of the morphological framework for sustainability assessment and to bolster sustainable urban design, a group of academics and professionals was consulted.

The assessment process entailed examining the relevance of the sustainable urban form parameters within the typological classification elements via conventional mathematical methods. Each indicator’s relevance was categorized into three levels, each denoted by a specific numerical value. For instance, within the Typo-morphological classification framework, professionals judged the integration of the ‘material’ element with ‘building material’ one of the indicators of ‘Efficiency’ based on its perceived importance. The results were classified as (1) for very relevant, (0.5) for relevant, and (0) for not relevant (see Table 2).

Moreover, the weighting exercise (see Table 2) was performed by a panel of 35 experts comprising architects, urban planners, and engineers who contributed a diverse set of perspectives on what drives ‘Efficiency’ in urban form. The experts assigned numerical values (1 for ‘very relevant,’ 0.5 for ‘relevant,’ and 0 for ‘not relevant’) to each indicator across the different morphological layers. Once statistically processed, “building material” emerged as consistently high-ranking, due to its clear impact on operational and embodied energy costs at the city scale. Although transportation systems also received considerable weight, many experts noted that transport outcomes are often influenced by policy-level decisions (for example, enhancements to public transport) or large-scale infrastructure investments beyond the direct control of smaller-scale design interventions. Consequently, this multi-tiered scoring approach helped illustrate how each indicator’s relevance can vary depending on whether it is applied at the micro (material) scale or the macro (city) scale. This clarifies why “building material” can sometimes surpass “transportation system” in the aggregated ‘Efficiency’ scores.

In order to further elucidate the rationale behind both the selection and weighting of indicators under each sustainable urban form parameter, we expanded our discussion of assessment methodology (see Section 3.2). The initial suite of indicators such as building material, transportation system, maintenance, and building design within the “Efficiency” category was derived from an extensive review of the literature addressing principal drivers of energy consumption and resource utilization. Building material, for example, received a higher score in the ‘Efficiency’ column because it exerts a direct and enduring influence on a building’s overall energy performance. Materials with superior insulation properties can dramatically reduce energy demand over the building’s entire lifespan, and the embodied energy from extraction or manufacture to installation can be notably high.

By contrast, although the “transportation system” indicator exerts a substantial effect on energy use, its efficiency often depends partly on broader infrastructural or policy factors that fall outside the immediate remit of a single urban project. This consideration explains why, during the expert weighting process, building material frequently attained a marginally higher and more direct impact within the ‘Efficiency’ dimension.

 

Comment #3: The authors do not explain the Methodology in detail, especially Figure 4 "the morphological framework". No merits can be found.

The authors agree that in the old version of the paper, the methodology has not been explained properly. As presented in Figure 4, this study lies in its structured three-stage approach, integrating urban morphology and sustainable urban form through a comprehensive methodological framework. In the first stage, the study introduces key urban morphology approaches, particularly the typo-morphological perspective and develops a classification framework grounded in scale hierarchy theory, serving as the input phase. The second stage addresses the concept of sustainable urban form parameters, contributing analytical tools to assess built environment from a sustainability perspective when considering the morphology of a city. Finally, the third stage synthesizes these findings through an integrated methodology, enabling the development and evaluation of a toolkit that reveals the evaluation of sustainability based on the relevance of the sustainable urban form parameters within typo-morphological hierarchical levels, constituting the output phase of the research.

To solve this issue, in the updated version of the paper, the final paragraph of the section 3.1 “Methodology”, has been changed from:

 

This study harmonizes these two essential components to propose a cohesive morphological framework for sustainability assessment (model), aiming to guide more sustainable urban design and development, as depicted in Figure 4.

to:

As presented in Figure 4, this study lies in its structured three-stage approach, integrating urban morphology and sustainable urban form through a comprehensive methodological framework. In the first stage, the study introduces key urban morphology approaches, particularly the typo-morphological perspective and develops a classification framework grounded in scale hierarchy theory, serving as the input phase. The second stage addresses the concept of sustainable urban form parameters, contributing analytical tools to assess built environment from a sustainability perspective when considering the morphology of a city. Finally, the third stage synthesizes these findings through an integrated methodology, enabling the development and evaluation of a toolkit that reveals the evaluation of sustainability based on the relevance of the sustainable urban form parameters within typo-morphological hierarchical levels, constituting the output phase of the research.

 

 

Comment #4: Figure 5, the subgraphs' numbers are not well labeled. Besides, R-square equals to 0.1431, and 0.1283, which are not significant.

 

The authors agree that in the old version of the paper the label of the Figure 5 was not well presented. To address this issue the updated version of Figure 5 is as follows:

 

 

(a)	(b)
(c)	(d)
(e)	(f)
(g)	(h)

Figure 5. Analysis of gathered dataset linked to the elements of material, structure, room, building, plot, street, and city (developed by the authors).

 

We appreciate the reviewer’s observation regarding the low R-squared values (0.1431 and 0.1283). The text has been revised to clarify that these values indicate weak correlations and are not statistically significant. However, we believe these preliminary results still highlight areas worth further exploration, potentially through nonlinear modeling or more targeted analysis in future work. To solve this problem, the following section in the updated version of the paper has been changed from:

 

The “Material”, “Plot”, and “Street” elements fall within the moderate correlation range, with R-squared values of 0.3432, 0.1431, and 0.1283, respectively, highlighting their significance while signaling a need for more comprehensive investigations into their nuanced dynamics.

to:

The “Material,” “Plot,” and “Street” elements exhibit varying levels of correlation, with R-squared values of 0.3432, 0.1431, and 0.1283, respectively. While the correlation for the “Material” element can be considered moderate, the relatively low R-squared values for “Plot” and “Street” suggest weak linear relationships. Although not statistically significant, these findings may still offer preliminary insights, indicating the need for deeper investigation into potential nonlinear patterns or contextual dependencies influencing these elements.

 

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

 This manuscript explored the relationship between key morphological layers and the degree of sustainability in urban form, and proposed an evaluation model that combined the type-morphology framework with the parameters of sustainable urban morphology，which was of great significance for evaluating the sustainability potential of urban design.

    However, there are several issues that need to be further improved and optimized.

   1) While the indicators of sustainable urban form parameters (e.g., efficiency, integrity) were listed, a brief explanation of how these indicators were selected or weighted would enhance understanding. For instance, why is "building material" scored higher than "transportation system" in the "Efficiency" column?  Please further explain or improve it.

  2) The authors acknowledge consensus among participants, but do not explicitly discuss potential limitations, such as sample bias (only 32 out of 35 responses were available) or regional specificity (e.g., applicability to non-European contexts). Suggestions for improvement and modification

 3) Some sections, like the description of typo-morphology and sustainable parameters, were repeated across the introduction and literature review. Streamlining these sections could improve readability.

Author Response

We are grateful to the reviewer for taking his/her time to review our work. Their comments have helped us to improve the paper. Changes to the original manuscript are given in Red in the revised version. Detailed responses to the reviewer’ comments are provided in the following lines:

 

Comment #1 While the indicators of sustainable urban form parameters (e.g., efficiency, integrity) were listed, a brief explanation of how these indicators were selected or weighted would enhance understanding. For instance, why is "building material" scored higher than "transportation system" in the "Efficiency" column?  Please further explain or improve it.

Thank you for your comment. According to the comments of the Reviewers, major changes were applied in the Analytical tools part to represent all the importance of the study more concise. We have now added a clear explanation of the criteria and rationale used by experts during the weighting process, including justification for the higher relevance of building material in certain contexts. Therefore, the modified version of the Chapters 2.4 “Sustainable urban form and its parameter” and 3.2 “Analytical tools”, in the updated version of the paper are as follows:

3.2 Analytical tools

A methodology was devised to evaluate the integration of various indicators pertinent to sustainable urban form parameters with typo-morphological elements, grounded in a classification framework spanning multiple scalesincluding the city level [49,67-69]. In accordance with this framework, a checklist was prepared using the proposed indicators. To validate the coherence of the morphological framework for sustainability assessment and to bolster sustainable urban design, a group of academics and professionals was consulted.

The assessment process entailed examining the relevance of the sustainable urban form parameters within the typological classification elements via conventional mathematical methods. Each indicator’s relevance was categorized into three levels, each denoted by a specific numerical value. For instance, within the Typo-morphological classification framework, professionals judged the integration of the ‘material’ element with ‘building material’ one of the indicators of ‘Efficiency’ based on its perceived importance. The results were classified as (1) for very relevant, (0.5) for relevant, and (0) for not relevant (see Table 2).

Moreover, the weighting exercise (see Table 2) was performed by a panel of 35 experts comprising architects, urban planners, and engineers who contributed a diverse set of perspectives on what drives ‘Efficiency’ in urban form. The experts assigned numerical values (1 for ‘very relevant,’ 0.5 for ‘relevant,’ and 0 for ‘not relevant’) to each indicator across the different morphological layers. Once statistically processed, “building material” emerged as consistently high-ranking, due to its clear impact on operational and embodied energy costs at the city scale. Although transportation systems also received considerable weight, many experts noted that transport outcomes are often influenced by policy-level decisions (for example, enhancements to public transport) or large-scale infrastructure investments beyond the direct control of smaller-scale design interventions. Consequently, this multi-tiered scoring approach helped illustrate how each indicator’s relevance can vary depending on whether it is applied at the micro (material) scale or the macro (city) scale. This clarifies why “building material” can sometimes surpass “transportation system” in the aggregated ‘Efficiency’ scores.

In order to further elucidate the rationale behind both the selection and weighting of indicators under each sustainable urban form parameter, we expanded our discussion of the assessment methodology (see Section 3.2). The initial suite of indicators such as building material, transportation system, maintenance, and building design within the “Efficiency” category was derived from an extensive review of the literature addressing principal drivers of energy consumption and resource utilization. Building material, for example, received a higher score in the ‘Efficiency’ column because it exerts a direct and enduring influence on a building’s overall energy performance. Materials with superior insulation properties can dramatically reduce energy demand over the building’s entire lifespan, and the embodied energy from extraction or manufacture to installation can be notably high.

By contrast, although the “transportation system” indicator exerts a substantial effect on energy use, its efficiency often depends partly on broader infrastructural or policy factors that fall outside the immediate remit of a single urban project. This consideration explains why, during the expert weighting process, building material frequently attained a marginally higher and more direct impact within the ‘Efficiency’ dimension.

 

Comment #2: The authors acknowledge consensus among participants, but do not explicitly discuss potential limitations, such as sample bias (only 32 out of 35 responses were available) or regional specificity (e.g., applicability to non-European contexts). Suggestions for improvement and modification.

 

Thank you for your comment. The required revision has been done. A paragraph discussing the limitations, particularly sample size and regional applicability has been added to the final part of the paper. The said paragraph is as follows:

 

Limitations and Further Research

While the findings showed a broad consensus among the 32 participants whose responses were deemed complete and valid, the authors recognized that excluding three incomplete submissions could introduce a mild sample bias. It is possible that those incomplete questionnaires may have represented different viewpoints, potentially influencing the final assessment outcome. Furthermore, although the one-way ANOVA indicated that the existing 32 responses were sufficiently consistent for meaningful results, the authors acknowledge that a higher response rate or additional participants from a variety of professional backgrounds could strengthen the robustness of the conclusions. Future research should therefore consider recruiting a larger and more diverse sample, possibly expanding beyond local academic circles to include practitioners and stakeholders from multiple regions. Moreover, the city samples and expert panels in our study leaned strongly towards European and Mediterranean contexts. While the core concept of applying typo-morphological frameworks and sustainability indicators can be adapted to most urban settings, the specific weighting of indicators might vary in non-European or rapidly urbanizing regions, where climatic conditions, cultural factors, or policy frameworks differ considerably. To address this limitation, subsequent studies could include case studies from diverse geographic areas to ascertain how well the proposed methodology translates to different climates, cultural practices, and regulatory environments. Incorporating these contexts will help refine the weighting system further, ensuring that parameters such as social equity, liveliness, and local building materials reflect the conditions of each region. By expanding both the sample size and regional scope, the proposed framework can evolve into a more universally applicable tool for assessing and guiding sustainable urban design.

Comment #3: Some sections, like the description of typo-morphology and sustainable parameters, were repeated across the introduction and literature review. Streamlining these sections could improve readability.

 

Thank you for your comment. The required revision has been done. We carefully reviewed and removed redundancies, ensuring that detailed definitions appear only once in the Literature Review while keeping the Introduction concise and focused. The changes in the updated version of the paper are as follows (Chapters 2.1 and 2.4):

2.1 Urban Morphology

Morphologists and urban designers concentrate on the tangible or material aspect of urban spaces, with urban elements serving as their shared connection or framework [8]. Urban morphologists analyze and categorize urban elements based on their characteristics, while urban designers typically employ a range of urban elements to craft three-dimensional urban environments. Additionally, the literature review delves into the concept of tools for classifying urban morphology. Through this tool, an attempt is made to explore an approach suitable for assessing sustainability in urban form using the parameters associated with sustainable urban development.

The examination of the structures and arrangements of the constructed environment in human settlements is referred to as urban morphology [9]. It serves as a method for comprehending the intricate and diverse settings of human settlements. Urban morphology involves scrutinizing the physical built form of urban areas, identifying key individual elements, and understanding their spatial arrangement [10]. Simply put, “urban morphology” can be defined as the study of spatial form [11]. Urban morphology recognizes that the physical form of a city undergoes changes over time and views the city as a dynamic process rather than a static object [6]. This approach is particularly applicable to research and practices focused on the environmental, economic, and social aspects of urban form [12].

 

2.4. Sustainable urban form and its parameters

 

A sustainable urban area is perceived as a region that achieves enduring physical, social, and economic development while maintaining continuous access to natural resources within sustainable limits and ensuring ongoing resilience against environmental threats [28]. Various theoretical models have been proposed to conceptualize sustainable urban areas: (1) compact, high-density urban form [29], (2) low-density decentralized urban areas [30], (3) decentralized concentration, and (4) models influenced by Howard’s Garden City [31]. In each approach, the core is a balance of environmental, social, and economic factors [32].

From a broader review, six fundamental parameters—efficiency, integrity, responsibility, acceptability, liveliness, and equity—are identified as primary contributors to a sustainable urban form [33-35]. Briefly:

-Efficiency: Optimizes energy consumption in buildings and transportation systems [33-36, 37-39].

-Integrity: Maintains compositional and historical coherence, preserving social and visual harmony [33,40-44].

-Responsibility: Safeguards resources, lowers pollution, and integrates advanced technologies to minimize environmental impact [45,46].

-Acceptability: Improves quality of life by ensuring social interaction, sense of place, safety, and overall satisfaction [47-54].

-Liveliness: Encompasses ecological diversity, social interaction, and vibrancy in the urban environment [55-60].

-Equity: Addresses access to resources, affordability, and job opportunities [7,57, 60-66].

Within this study, these parameters serve as the main criteria for evaluating sustainability via the typo-morphological framework described earlier. In the following sections (3 and 4), we illustrate how each parameter interacts with a particular morphological layer—ranging from material to city—and provide a statistical validation of the approach.

Author Response File: Author Response.docx

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The authors made significant modifications about this paper which is more clearly. Hereby, I have some minor revisions:

1. In 3.1. Methodology, the first and second paragraphs present the authors develop a toolkit. The authors explain the basic idea of the method, but it is not detailed. A well-designed methodological schematic (not like figure 4) is necessary.  

2. More literatures about urban sustainability and form should be cited in this paper, like "Topological analysis of urban street networks. Environment and Planning B, 31(1), 151–162.", "Street-based topological representations and analyses for predicting traffic flow in GIS. International Journal of Geographical Information Science, 23(9), 1119–1137", "Agglomeration centrality to examine spatial scaling law in cities, Computers, Environment and Urban Systems 77 (2019) 101357", "Cities as organisms: Allometric scaling of urban road networks. Journal of Transport and Land Use, 1(1), 21–39.", "Agglomeration centrality examination of cities: an urban transport perspective, Sustainable Cities and Society 61 (2020) 102273", "Centrality measures in spatial networks of urban streets. Physical Review E, 73(3), 036125".

Author Response

Authors response to Reviewer Comments

Manuscript title:

The nexus of morphology and sustainable urban form parameters as a common basis for evaluating sustainability in urban form

 

We are grateful to the reviewer for taking his/her time to review our work. Their comments have helped us to improve the paper. Changes to the original manuscript are given in Red in the revised version. Detailed responses to the reviewer’ comments are provided in the following lines:

 

Comment #1 In 3.1. Methodology, the first and second paragraphs present the authors develop a toolkit. The authors explain the basic idea of the method, but it is not detailed. A well-designed methodological schematic (not like figure 4) is necessary.

The authors agree that in the old version of the paper a detailed explanation of the method was not presented. To solve this problem, the following paragraph has been added to the Section 3.1 in the updated version of the paper:

Therefore, this research develops a methodological toolkit to evaluate the built environment while providing a framework to facilitate the complex relationships between the physical form of the urban environment and its performance to inform the design and development of more sustainable urban form. Through a typo-morphological approach rooted in the theories of Conzen, Caniggia, Maffei, and Kropf, the study links hierarchical layers of urban form from materials to the city scale with six key sustainability parameters. Expert evaluations were collected and analyzed using statistical methods, including ANOVA and regression, to validate the structure and identify the morphological elements most influential in shaping urban sustainability.

 

 

In addition, the following explanation has been added to the section 2.4.5 in the updated version of the paper:

 

As it is mentioned, urban networks encapsulate key characteristics of urban planning and socio-economic activity, fostering social dimension, connectivity, and social interaction core elements that improve liveliness within a sustainable urban form [61-63].

 

Comment #2: More literatures about urban sustainability and form should be cited in this paper, like "Topological analysis of urban street networks. Environment and Planning B, 31(1), 151–162.", "Street-based topological representations and analyses for predicting traffic flow in GIS. International Journal of Geographical Information Science, 23(9), 1119–1137", "Agglomeration centrality to examine spatial scaling law in cities, Computers, Environment and Urban Systems 77 (2019) 101357", "Cities as organisms: Allometric scaling of urban road networks. Journal of Transport and Land Use, 1(1), 21–39.", "Agglomeration centrality examination of cities: an urban transport perspective, Sustainable Cities and Society 61 (2020) 102273", "Centrality measures in spatial networks of urban streets. Physical Review E, 73(3), 036125".

 

Thank you for your comment. All the proposed papers have been added to the updated version of the paper, as they are related to the associated sections.

 

Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

 The revised version of the paper has met the publication requirements and is agreed to be published.

Author Response

Authors response to Reviewer Comments

Manuscript title:

The nexus of morphology and sustainable urban form parameters as a common basis for evaluating sustainability in urban form

 

The authors appreciate the reviewer for acceptance of the paper.