Beyond green buildings: how green certification systems contribute to the dual imperative of environmental/well-being outcomes through the lens of SDGs

Environmental degradation persists due to climate change, rapid urbanization, and health-related challenges. The built environment has a critical role in addressing these problems, particularly with respect to carbon dioxide generated during construction and its effects on human health. According to a recent report by the United Nations (UN) Environment Program, the physical environment accounts for 39% of worldwide energy-related carbon dioxide emissions and 34% of global fossil fuel consumption (Global Alliance for Buildings and Construction, 2025). Simultaneously, 3.8 million premature deaths per year are estimated by the World Health Organization (WHO) due to stroke, respiratory, and cardiovascular diseases, associated with inadequate indoor environmental qualities (IEQs). Poor ventilation, exposure to toxic pollutants, and poor thermal conditions are among the factors that significantly contribute to health problems (WHO, 2021).

Certification schemes for sustainable and green buildings have therefore emerged to become market-driven tools to address the negative impacts. The best known of all these are the Building Research Establishment Environmental Assessment Method (BREEAM), Leadership in Energy and Environmental Design (LEED), and the WELL Building Standard (WELL). These standards, initially focused on environmental performance, have evolved over time. The holistic life-cycle assessment (BRE, 2025), the global standard for energy and sustainable site development (USGBC, 2025), and an evidence-based health-first model (IWBI, 2025) were all first to market through BREEAM, LEED, and WELL, respectively. This progression reflects an increasing recognition of the “dual imperative,” which demands sustainability alongside the fulfillment of well-being needs.

The UN (2023) Sustainable Development Goals (SDGs) offer a valuable framework for operationalizing this dual imperative by explicitly connecting environmental targets (e.g. SDGs 7, 11, and 13) with health and well-being goals (SDG 3). While there is existing literature on different certifications (Leite Ribeiro et al., 2025; Olabi et al., 2025; Shuang et al., 2024; Ferreira et al., 2023; Ascione et al., 2022; Röck et al., 2020; Berardi, 2017; Doan et al., 2017; Cole, 1998), a systematic and quantifiable analysis of how these certifications put health and environmental targets in an integrative structure is rarely conducted. Many studies are descriptive or treat standards as homogeneous, neglecting to unpack the relative credit structures that drive their differences in environmental performance.

This study aims to fill the gap by providing a comprehensive comparative analysis of the BREEAM, WELL, and LEED standards in relation to SDGs. The study had three main objectives:

1. Measure the relative balance of attention between environmental sustainability and human health control.

2. Assess alignment with the SDGs using a new weighting of certification criteria to draw attention to priorities and gaps.

3. Design a new concept and method by introducing the Integration Index to assess the nexus of environmental and health aspects, thereby measuring sustainability performance.

By using a mixed-methods approach to explore primary certification documents, this study makes explicit evidence-based knowledge. The results are expected to provide guidance to government bodies, architects, and developers seeking to align building practice with the cohesive principles of the global sustainability agenda, and therefore, enabling them to deliver built environments that are green and healthy.

Green building certification standards can be seen as a revolution in the construction sector, making it more sustainable and transparent. The provisions include criteria for the certification and assessment of a building’s environmentally sensible and socially acceptable performance. Earlier studies on the sustainability and performance ratings of buildings, such as those by Levin (1997) and Cole (1998), focused mainly on engineering issues, including energy conservation and materials technology, without much consideration of occupant health. This early orientation reflects the industry’s primary concern to mitigate its substantial environmental footprint.

BREEAM, established in the UK in 1990, is the first scheme to introduce the concept of a holistic life-cycle assessment method (Ding, 2008). Started in the United States in 1998, LEED became a global market-based reference standard with criteria that are focused on energy and water savings (Leite Ribeiro et al., 2025; Kibert, 2012). Launched in 2014, the WELL Building Standard focused on human health and wellness as significant evidence for a “health-first” assessment method (IWBI, 2025).

Although there are other rigorous standards, which place greater emphasis on lifecycle costing and performance as well, namely the DGNB in Germany (DGNB, 2023; Ferreira et al., 2023), CASBEE in Japan, and Green Star in Australia, attention in this study is being given to three internationally recognized systems that are structurally rather distinct: BREEAM, LEED, and WELL. These systems were chosen because they are widely used globally, offer contrasting evolutionary paths (holistic building approach, market-friendly, and health-focused), and are growing in popularity in dual certification projects, making a comparative analysis necessary to better understand integrative sustainability (WGBC, 2023).

The central premise of this research is the “dual imperative” to simultaneously advance environmental sustainability and human well-being for the built environment. The idea is based on emerging thinking that views environment and health as interdependent; the health of human societies is inextricably intertwined with and dependent upon the health of their environments (Whitmee et al., 2015).

This dual need is addressed through the United Nations Sustainable Development Goals (UN SDGs), which include environmental goals (e.g. SDG 7: Affordable and Clean Energy, SDG 11: Sustainable Cities, and SDG 13: Climate Action) that are linked to health and well-being (SDG 3), as well as social equity aspirations. This integrated approach views the SDGs as a suitable filter for examining the comprehensiveness of green building certification systems. However, the challenge is moving from an intuitive sense of connectedness to a quantifiable measure. This requires a shift from assessments in siloes, where such environmental and health metrics tend to be considered separately, to joined-up evaluations that consider the synergies, trade-offs, and compromises across these domains (Berardi, 2011; Sachs, 2012).

The contributions of the certification system to sustainability will be assessed through two complementary axes. The first is Balance (Coverage), which represents criteria for environmental and health-related SDGs. The second is Synergy (Interconnection), which includes criteria representing advancements in environmental and health modules. Figure 1 presents the conceptual framework of the research, placing the “Integration Index” as a quantitative instrument to capture how certification systems express the integrated nature of the SDGs and environmental-health paradigm.

There is extensive research comparing green building certification systems, yet coverage often reveals methodological shortcomings that this article seeks to address. Preliminary comparisons, such as the meta-analysis conducted by Doan et al. (2017), identified performance discrepancies and found that the obligatory post-occupancy evaluations (POEs) of BREEAM consistently produced better energy performance than LEED. However, this research discussed a few environmental indicators. The health effects of certificates have also been studied; MacNaughton et al. (2017) and Ildiri et al. (2022) reported substantial improvements in cognition, decision-making, and occupant satisfaction between WELL- and LEED-certified spaces. Yet, these bodies of work largely move in parallel, while empirical research that directly investigates trade-offs or synergies between environmental and health goals is scarce within an integrated analytical framework.

Moreover, although the alignment of certifications with the SDGs has been identified (Röck et al., 2020; Berardi, 2017), methods have generally been qualitative or descriptive rather than systematic, weighted, and transparent in valuing the relative contributions of certification systems to specific SDGs. This gives rise to the first research gap: there is no systematic, objective way of assessing (quantitatively) how well green building certifications align with the SDGs.

The second research gap reflects the lack of in-depth study of health-environment trade-offs and linkages. Sometimes certifications create conflicts; for example, highly sealed buildings with minimal fresh-air exchange can be prone to poor indoor air quality and inadequate natural ventilation if site planning is not adequately addressed. However, when discussing these conflicts, few studies examine how much certification promotes the active use of synergistic credits to address them.

Thirdly, there is a lack of uniformity in the assessment of levels. Most research treats certifications as binary (certified/uncertified); however, information on whether the stricter demands correspond to more holistic sustainability contributions remains scarce and fragmented across high-level certifications, such as LEED Platinum production (Eichholtz et al., 2013).

Fourthly, scholars such as Abu Qadourah and Alnusairat (2025), Al-Jokhadar et al. (2023), Alnusairat et al. (2021), and Altomonte et al. (2020) highlighted limitations, including insufficient consideration of social equity in these frameworks. Despite the focus on SDG 1 (No Poverty), SDG 5 (Gender Equality), or SDG 10 (Reduced Inequalities), certification schemes are criticized for failing to explicitly address these social aspects, potentially reinforcing sustainability as a privilege.

To fill the research gaps noted above, this study employs a mixed-methods approach and performs weighted quantitative analysis, cutting with qualitative classification, and analysis of materials. The aim is to develop a transparent system that enables reproducible testing of the integration of environmental and health aspects into green building certification systems, as demonstrated through the SDG framework assessment. The three-stage flow of the research approach is shown in Figure 2: (1) Data Collection and SDG Mapping; (2) Quantitative Weighting and Index Development; and (3) Gap and Synergy Analysis.

To provide a contemporary and comparative analysis, three of the most current certification systems for new construction and major renovation projects were selected: BREEAM New Construction (NC) v7 (2025), LEED Building Design and Construction (BD + C) v4.1 (2025), and WELL v2 (2025). For comparison, the chosen systems demonstrate state-of-the-art technologies through their equivalent operational capabilities.

The evaluation followed the criteria set in official technical manuals and guidebooks, including BRE (2025), USGBC (2025), and IWBI (2025). Certification entities justified their aims through SDG crosswalks and mapping documents, which served as secondary sources.

The approach aimed at mapping each credit/prerequisite in each system to the most relevant UN SDG. The research team adopted a strict protocol to avoid bias and maintain objectivity.

• Primary SDG Assignment: Each credit was assigned to a primary SDG according to its basic intention and the main objectives it fulfills. This process was preferred to avoid double-scoring and to facilitate straightforward point assignment.

• Mapping Foundation: Credit standards corresponded directly to the official UN SDG indicators and targets available in 2023. For instance:

  • The LEED credit “Optimize Energy Performance” was related to SDG 7 (Affordable and Clean Energy).

  • The WELL concept “Air Quality Monitoring” was associated with SDG 3 (Good Health and Well-being).

  • The BREEAM credit “Green Roofs” was related to SDG 11 (Sustainable Cities and Communities) for its ability to reduce urban heat island effects.

• Management of a Multi-dimensional Credit System: SDGs were used to allocate credits with direct and desired results. For instance, “Natural Ventilation” was categorized under SDG 3 (Health) because it directly reduced indoor air pollution; however, its indirect reduction of Greenhouse Gases (GHGs) indicated that it contributed to SDG 7 (Energy) after the formal evaluation using the Synergy Score.

• Inter-Rater Reliability Analysis: Two researchers worked independently to produce the mapping and establish code consistency. Strength comparison yielded an inter-rater reliability of 0.88 (Cohen’s Kappa), indicating strong agreement between coders (Cohen, 1960). All discrepancies involving fewer than 5% of the credits were discussed and reconciled with a third senior investigator.

The credit points for all systems were normalized to a 100-point scale. Therefore, different total point scores of the various rating systems could be compared directly using Formula 1 (Normalized Credit Value (Authors)).

The contribution percentage for each SDG was obtained by summing the normalized points from all credits linked to that goal, as per Formula 2 (SDG Percentage Contribution (Authors)).

Environmental SDGs were defined as SDGs 6, 7, 11, 12, 13, 14, and 15, whereas the health SDGs were identified as SDG 3. This allowed easy computation of an aggregate environmental and health focus indicator for each system.

The Integration Index is designed as an integrative performance assessment tool to assess the system’s ability to reach environmental targets and health goals in balance. It comprises two components: Coverage Balance and Synergy Score.

1. Coverage balance

This metric shows the relative importance of environmental SDGs in comparison to health SDGs. A perfectly balanced system has a 50/50 split. This factor receives 50% weight, as the core concept of “the duality imperative” states that both environmental and health aspects are equally crucial for overall sustainability. A one-dimensional, highly specialized system, no matter how synergistic it might be with another dimension, is not a fully integrating system if the other dimension does not receive due consideration. The score was calculated as 100 minus the absolute deviation from perfect balance, as shown in Formula 3 (Coverage Balance (Authors)).

1. Synergy Score

This score is the fraction of system credits that directly support environmental and health benefits. The researchers took a qualitative approach to scoping “dual benefit” credits by examining credit requirements and their relation to the SDGs. Examples include:

• The WELL Standard allows Circadian Lighting Design to support user sleep quality and health efficiency (SDG 3) by integrating daylight harvesting systems that conserve energy and promote sustainability (SDG 7).

• LEED Standard encourages Low Emission Materials to promote indoor air quality (SDG 3) and sustainable production systems (SDG 12).

• BREEAM Green Roofs satisfy double functionality of fighting urban heat-island effects and stormwater runoff (SDGs 11 and 13) and constitute at the same time a natural access factor mitigating stress (SDG 3).

The Synergy Score is the percentage of the overall normalized points that come from dual-benefit credits between systems. This score receives 50% weight because effective integration is not just a matter of financial balance; it requires an active credit design that creates good results while accommodating multiple competing demands. The overall Integration Index is obtained as a weighted sum of the two components, as shown in Formula 4 (Full Integration Index (Authors)).

The study used a 50/50 weighting system as a base assumption and conducted a sensitivity analysis to assess the final ranking outcomes. The Integration Index was rescaled according to two different weighting scenarios.

• Scenario A: 60% Coverage Balance and 40% Synergy Score.

• Scenario B: 40% Coverage Balance and 60% Synergy Score.

The third stage involved synthesis of the qualitative and quantitative findings from Phases 1 and 2. This included:

• Gap Analysis: Indicate the least SDGs covered in all three certification systems.

• Conflict Identification: Study credit policies to determine potential trade-offs between energy efficiency measures and opportunities for adaptive thermal comfort.

• Strategic Recommendations Development: The synthesis of quantitative and qualitative data analyses enables the development of evidence-based recommendations to improve integration between certification systems by adjusting current credits and providing for dual-benefit credits.

This section presents the results of the study. The analysis is structured to enable comparison of the certification systems, followed by a detailed evaluation of their SDG alignment and an assessment of their integration performance using the Coverage Balance, Synergy Score, and composite Integration Index.

A comparison of the credit structure reveals each system’s priorities. Figure 3 shows that BREEAM NC v7 distributes the scoring across nine categories and assigns emphasis on Energy (21%) and Health and Well-being (15%). This spread indicates an underlying intention to unify these two most fundamentally important areas. LEED BD + C v4.1 has a strong environmental emphasis, from which 33% of its points are derived in the Energy and Atmosphere category, to which Indoor Environmental Quality (IEQ) contributes 10%. Conversely, WELL v2 focuses on 10 human health concepts and allocates the highest points to Air (16%), Water (11%), and Mind (11%), institutionalizing its health-first paradigm. This variation in structure has implications for how each system aligns with the SDG framework, as shown in the mapping of the SDGs in Figure 4.

A statistical assessment of weighted SDG contributions revealed distinct strategic profiles across certification schemes and significant shortcomings in the holistic approach to sustainability.

The alignment of SDGs with LEED is dominated by environmental objectives, which are the most heavily weighted (79.1% of the total score), as illustrated in Table 1. SDG 7 (Affordable and Clean Energy) is the highest at 30%, followed by SDG 11 (Sustainable Cities) at 16.4%. Health-related goals, predominantly SDG 3 (Good Health and Well-being), represented a lower weight (12%). Notably, social equity goals (SDGs 1, 2, 4, and 5) showed zero contribution from LEED.

The WELL v2 standard aligns 72.5% of its weight with health-focused goals, with a dominant focus on SDG 3, as presented in Table 2. However, its environmental integration is weak, as only 12.5% of its contributions support SDG 13 (Climate Action) due to the available credits for reducing energy consumption. WELL’s coverage of social equity objectives is insignificant (<2%), indicating a broader void despite its focus on people.

BREEAM has the most even split between environmental and health imperatives. Its contributions are weighed most heavily in the environmental goal area (57%), with a strong focus on SDG 7 (16.5%) and SDG 15 (10.5%). It allocates 23% to the health targets, mostly to SDG 3 (15%), as shown in Table 3. Although this corresponds to the fairest coverage among the systems, BREEAM falls short of social equity SDGs (<2%), suggesting that a balanced focus on environmental and health-related concerns does not automatically lead to broad social sustainability.

Figure 5 presents the contributions of the three systems to the 17 SDGs, providing a proper visual representation of the divergent specialisms of LEED and WELL and a more balanced approach reflected in BREEAM. It should be noted that all three systems are universally poor at achieving social and aquatic objectives.

Coverage Balance considers the distributional fairness between environmental and health priorities. LEED had the highest imbalance (64.6) and the Coverage Balance score of 67.7, indicating an environmental focus. WELL, on the other hand, being primarily health-related, showed better relative balance (imbalance of 43.4) with a score of 78.3. This is because its health focus has an inherent environmental component (e.g. water use and waste), limiting a greater disproportionate impact. BREEAM had the lowest imbalance (34.0) and the highest Coverage Balance (83.0), indicating the most even distribution of credits between the two imperatives.

The Synergy Score represents the extent to which each system is intended to generate co-benefits, from passive intersection to active integration. The integration flexibility varied among the three systems. LEED achieved the least integration; only 12% of its credits delivered combined benefits. Most of its credits, even those that cover only energy modeling or refrigerant management, are structured as standalone environmental interventions. BREEAM performed in the middle, with a score of 28% on the Synergy Score Credits that address thermal comfort and energy efficiency, such as “Heating and Cooling,” demonstrating a moderately intentional integration. On the other hand, WELL presented the highest Synergy Score of 38%, because health-oriented strategies are often intended to serve environmental co-benefits. For example, its “Natural Ventilation” credit directly supports healthy indoor air quality (health) by minimizing the reliance on mechanical systems while using less energy (environment).

The composite Full Integration for each system is a combined measurement of the performance, as supported by the results summarized in Table 4.

• LEED (Integration Index = 39.9): The Environmental Specialist. The low LEED score was driven by a low Synergy Score (12%), suggesting weak integration of environmental and health agendas. The strength of LEED comes from its environmentally friendly characteristics rather than its integrative resin balance.

• BREEAM (Integration Index = 55.5): The Balanced Integrator. Its score was based on a high Coverage Balance (83.0), which more than offset an average Synergy Score (28%). The claim is well balanced, but there remains a substantial area for further active integration.

• WELL (Integration Index = 58.2): The Health Innovator with Green Benefits. Its strong synergy mining played a role in posting the top integration score (38%), due to its health-first mode of operation. This indicates that a narrow specialization, if well-designed, can lead to integration at broad scales.

Sensitivity Analysis: To assess the stability of the above-mentioned ranks, the Integration Index was recalculated using alternative weights. At the 60/40 scale weighting split (towards Coverage Balance), BREEAM scores 61.0, which is slightly lower than WELL (62.09), reflecting that the coverage-based strength plays a role. When using a 40/60 weighting (towards Synergy), WELL widened its advantage to 54.12, against BREEAM’s score of 50.0. Notably, LEED consistently emerges as the least integrated system of all scenarios, and a WELL-BREEAM match rivalry suggests that which system is considered most integrated depends on whether synergistic design or balanced coverage is preferred. This confirms that the key results are robust and that, despite the ordinal ranking of WELL versus BREEAM, they are sensitive to the assumed weights.

Integration is achieved through a qualitative analysis of high-synergy credits. Representative examples of each system are summarized in Table 5. For instance, WELL’s “Circadian Lighting Design” and BREEAM’s “Green Roofs” feature credits intended to satisfy a “dual imperative.” In comparison, LEED’s high-synergy credits, such as “Low-Emitting Materials,” are fewer in number and are typically considered more of a side-effect than a design core.

In conclusion, LEED’s strength is the depth of its environmental credentials, but it lacks an integrated design at its core. WELL successfully capitalizes on a health focus to create strong synergies from a niche start, and BREEAM offers the most well-rounded coverage, though it has potential to strengthen the active interconnection of its criteria further. However, all three systems have high limitations in promoting social equity.

This study quantitatively evaluates the integration of health and environmental goals across three leading green building rating systems using a new Integration Index. The findings present a combined view in which each of the three systems has endeavored to contribute to sustainability. Yet, there are different, sometimes conflicting understandings and actions that yield varying “good results” in relation to the “dual imperative” arena. Interpretation of these findings is discussed in relation to the conceptual framework and research gaps; their implications are considered, and the study’s limitations are acknowledged.

The profiles identified by the Integration Index, represented by LEED, ranked as “Environmental Specialist,” WELL as “Health Innovator,” and BREEAM as the “Balanced Integrator”, constitute an engaging and differentiated typology beyond an overly simplified grouping. This helps explain the growing trend of dual certification in the marketplace (e.g. LEED + WELL) at the project scale, which aims to counterbalance and overcome the inherent single-system specialization within certifications (Röck et al., 2020). However, there is no single system that adequately captures the integrative concept underpinning the SDG framework.

Remarkably, WELL scored highest in the level of integration index amongst our findings. This calls into question the notion that a balanced scorecard is necessarily the only route to integration. Instead, it illustrates how the weight of resources can naturally lead to significant environmental co-benefits through design logic when put on health over time. This is empirical support for the hypothesis “health as a sustainability driver,” as presented in the work of Altomonte et al. (2020). In contrast, LEED’s low synergy score (12%) supports prior criticisms of its fragmented strategy, in which energy productivity is often pursued independently of occupant health outcomes (Newsham et al., 2009).

Furthermore, the persistent underrepresentation of social equity SDGs (<2% of all systems) is a key result. This suggests that despite their transformation, contemporary certifications remain embedded in a techno-environmental discourse and have not completely assimilated the social and distributive justice aspects at the heart of the SDGs’ pledge to “leave no one behind”, a gap increasingly underscored by researchers (Abu Qadourah and Alnusairat, 2025; Ascione et al., 2022; Yeganeh et al., 2019).

This research was conducted to address previously identified methodological limitations, and several notable contributions can be attributed to the methods.

In response to the systemic SDG alignment gap, the study contributes to existing literature by leveraging an explicit, weighted, and normalized protocol for mapping SDGs, demonstrating cross-coder consistency compared to the qualitative approximations that have characterized prior work (e.g. Berardi, 2017). Our approach permits straightforward quantitative comparison of SDG priorities and provides a replicable methodology for future research.

The study quantified health–environment trade-offs and synergies by introducing the Synergy Score and Coverage Balance, which deliver a direct response to the under-analyzed question around trade-offs. The study moved from observing that trade-offs exist to measuring how systems are specifically designed to overcome them. The Integration Index provides a tangible tool for measuring “integratedness.”

Furthermore, the research offered nuanced insight into certification tiers. Whereas it focused on systems at the credit structure scale, the method described can serve as a foundation for future research to unpack differences across certification tiers (e.g. Certified versus Platinum). The normalized scoring system can be used to test whether more advanced certifications lead to better integration, helping to avoid the criticism made by Eichholtz et al. (2013).

Finally, it highlighted the equity gap in certifications by quantifying the least weight given to social SDGs, revealing a systemic blind spot and creating a benchmark for future developments.

The findings have concrete implications for various stakeholders in the built environment. For certification bodies (USGBC, IWBI, and BRE), the study’s output is a diagnostic tool that supports strategic evolution. Rather than general calls for “improvement,” our investigation lays out concrete, evidence-based paths to reform. The following pathways are proposed as strategic, research-based steps for each system, with consideration of its strengths and weaknesses.

• Elevating LEED’s Integration: To tackle its integration problem, LEED might add “Health Co-Benefit” options to existing environmental credits. For example, the “Optimize Energy Performance” credit statement could include an exemplary performance point for projects that demonstrate a correlated improvement in indoor air quality metrics and encourage HVAC designs that address energy efficiency and health considerations.

• Amplifying WELL’s Environmental Reach: While retaining its focus on health, WELL can more overtly increase its environmental relevance through updating its credits that link health resilience with renewable energy. A potential “Health Resilience Power” credit could require an on-site renewable energy system that supports essential health services, consistent with SDGs 3 and 7.

• Advancing BREEAM’s Synergy: BREEAM offers a strong backbone for evidence-based integration. It could enhance credits like “Thermal Comfort” by requiring post-occupancy validation of energy-efficient retrofits to verify that any measurable gains in occupant comfort and well-being have been achieved. This strategy could convert passive overhits into active, confirmed dual outcomes.

For policymakers and planners, cities and countries can use the findings to guide green building requirements and incentives. Policies can encourage projects that receive dual certification or high scores based on integrative metrics, thereby shifting the conversation from checklists to performance-based outcomes and aligning with the aims of the SDGs.

For developers and designers, the Integration Index provides a decision-making tool for selecting a certification system that aligns with the project-specific goals. For instance, a developer prioritizing carbon reduction might find LEED more complementary, whereas one focused on occupant comfort and brand differentiation in the corporate wellness space might lean towards WELL, and a public project looking for a balanced approach might choose BREEAM. Moreover, the application of dual-benefit credits would require further integration of architects, engineers, and health professionals to collaborate at a project’s early stage (Alnusairat et al., 2025; Elnagar et al., 2024; Ikudayisi et al., 2022).

Although this study represents a new analytical framework, several limitations and potential areas for further research are identified.

• Methodological Scoping: While promoting clarity, the focus on a single primary SDG per credit uncovers the multidimensional impact of some credits. Prospective studies should investigate other mapping-assignment details.

• System Selection: The attention towards BREEAM, LEED, and WELL means that other relevant systems (e.g. DGNB and Green Star). Generalizing this interpretation into a larger ensemble of global and regional systems would certainly provide a more unified perspective.

• Theoretical Weighting: Although the 50/50 weighting in the Integration Index was justified based on evidence and sensitivity tested, it is still a construct. Stakeholder surveys (e.g. policymakers, developers, and occupants) might be used in future research to obtain empirically derived weights.

• Lack of Performance Validation: The analysis only assessed impact potential as enshrined in the credit framework, not the actual performance of certified buildings. An important next stage is to conduct long-term post-occupancy studies of buildings across different certification levels and types to determine whether higher integration scores are associated with superior real-world environmental and health performance.

• Climatic and Regional Applicability: Future studies should examine how the effectiveness of integrative credits is sensitive to climate and culture, for example, in terms of natural ventilation in tropical vs. temperate climates, as well as regional adaptation of certification systems.

In conclusion, this paper classified existing systems and presented a new approach and tools for quantifying, evaluating, and improving the integrative performance of green building standards, by pivoting the discussion away from the “what” these systems do to process, toward the “how well” they link critical sustainability concerns.

This research systematically compares the environmental and health integration in three leading green building certification systems: LEED, BREEAM, and WELL, using the UN Sustainable Development Goals (SDGs) as a unified framework. Utilizing a novel methodological approach that combines weighted SDG mapping with a composite Integration Index, this paper provides quantitative, transparent, and comparable empirical evidence on how these systems balance and interconnect the “dual imperative” for environmental sustainability alongside human health.

The results support the idea that the three systems fill different specific niches. The LEED continues to specialize in the environment, performing relatively well on environmental SDGs (79.1%), with minimal health integration (12%) and synergy. WELL, by confirming its role as a health innovator with a strong health focus (72.5%) and, through intentional design, achieving the highest level of health-environment synergy (38%). BREEAM is the fairest integrator, with a more balanced coverage split between environmental (57%) and health (23%), and a medium level of synergy. Notably, the analysis identifies the complete absence of social equity focus (<2%) across all systems. This reveals a substantial detraction from the holistic, equity-based aspirations of the 2030 Sustainable Development Goals.

The key contribution of this work is the methodology used. The resulting framework (including the Coverage Balance, Synergy Score, and complete Integration Index) offers a reproducible method for diagnosing the integrative potential of sustainability standards. This empirical analysis fills an important gap in previous studies. It provides certifying organizations, policymakers, and researchers with a tool to move away from fragmented assessment toward an integrated understanding of how building standards can simultaneously promote different sustainability goals.

The study’s practical implications are two-fold. For industry professionals, the results suggest that dual certification (e.g. LEED + WELL) should be considered to ensure holistic sustainable impacts. For certification agencies, the findings provide a tangible, evidence-based road map for strategic change. The potential pathways —strengthening health co-benefits in LEED, broadening environmental metrics in WELL, and intensifying active synergies in BREEAM—are rational steps forward, grounded directly in where a performance deficiency is identified.

The study provides a foundation for numerous important lines of future inquiry. First, there is a call for performance validation studies that correlate structural facts with concrete, physical realities through longitudinal post-occupancy evaluations using IoT sensors to monitor energy consumption and indoor environmental quality (IEQ). Second, it is a question of regional adaptation and the development of certification schemes that fit tropical, arid, or developing regions to achieve global equity in sustainable building. Third, integrating social equity requires further development of how to directly embed affordable access, community benefits, and inclusivity into the design of certification credits. Finally, the potential impact of emerging technologies, such as real-time building optimization using artificial intelligence and transparent auditing and performance analysis incorporating blockchain, in addressing some of the identified gaps, needs further exploration.

Finally, moving towards a sustainable built environment requires shifting away from fragmented solutions. While the study’s findings indicate that current green building certifications are effective, they are not fully aligned with the holistic, integrated character of the SDGs. In measuring their strengths and weaknesses, the study points the way forward, requiring envisioning future standards and practices that do not simply reduce carbon emissions or enhance health in isolation, but cleverly and equitably bind environmental sustainability with well-being.