Hybrid Façades: A Systematic Review of Integrating Vertical Greenery Systems with Advanced Façade Technologies

Abstract

Intending to improve building performance and environmental sustainability, vertical greenery systems (VGSs) are employed as effective nature-based solutions (NbSs), yet they often struggle to meet modern building energy demands alone. This study investigates the integration of VGSs with advanced façade technologies (AFTs) to develop multifunctional hybrid façades. A systematic review was conducted following PRISMA 2020 guidelines, combining bibliometric and thematic analyses of 415 publications (2015 to early 2026) from Scopus and Web of Science. The study categorizes AFT into adaptive, energy-generating, and high-performance façades. The results indicate that VGS–photovoltaic (PV) systems and double-skin (DS) systems are the most studied integration scenarios, providing significant thermal regulation and energy efficiency. However, significant gaps remain for kinetic, modular, bioactive, and glazing systems, particularly regarding standardized workflows and long-term lifecycle assessments (LCAs). The study reveals a transition of VGSs from passive aesthetic elements to active building components. To address these identified gaps, a four-phase design strategy—conceptualization, hybridization, optimization, and development—is proposed to guide architects and engineers in decision-making regarding generating optimized hybrid façades. Integrating VGSs with AFTs is essential for urban resilience and an alignment with Sustainable Development Goals. Future research should prioritize standardized integration protocols and the application of smart technologies like artificial intelligence (AI).

1. Introduction

In recent years, the building sector accounts for approximately 40% of global energy consumption and 30% of greenhouse gas emissions, making sustainable building envelope design a critical priority for climate change mitigation [1,2,3]. As urbanization accelerates, the need for innovative and integrated façade systems that exceed simple barriers to become effective technologies embedded within the building envelope is increasing [3,4]. In this context, vertical greenery systems (VGSs) have emerged as vital nature-based solutions (NbSs) for urban cooling and biophilia; however, a VGS alone is insufficient to meet the complex energy demands and population density of modern cities [5,6,7].

To move beyond the limitations of standalone VGSs, an innovative strategy is required: the integration of VGSs with advanced facade technologies (AFTs) [5,6,7]. This synergy is essential because it evolves the building skin from a passive biological envelope into an active, multifunctional envelope for climate change mitigation and urban area regeneration [8,9]. By integrating VGSs with AFTs, such as kinetic, modular, photovoltaic (PV), bioactive, double-skin (DS), and glazing systems, designers can create “hybrid façades”, which are not merely a coexistence of two systems, but rather a unified building envelope system [1,10,11,12,13]. These hybrid façades integrate nature-inspired components with technological elements that function as a single unit to achieve synergistic performance that neither system can provide on its own, thus warranting further investigation into their potential to improve building performance indicators [1,10,11,12,13]. This integrated approach is also essential for aligning with the United Nations Sustainable Development Goals (SDGs), specifically those targeting healthy living (SDG 3), clean energy (SDG 7), resilient cities (SDG 11), climate change mitigation (SDG 13), and promoting biodiversity (SDG 15) [14,15,16].

While previous reviews have focused on the performance of VGSs or AFTs as independent functions with separate efficiencies, such as the study by Raji et al. [17], who analyzed greening systems for thermal regulation and energy efficiency, the study by Omrany et al. [18], who categorized types of VGSs to improve building performance, and the study by Zhou and Herr [19], which examined the efficiency of AFT as an additive façade element, the integration of these multifunctional systems (VGS-AFT) to form a unified hybrid façade remains largely unexplored. Based on a combination of bibliometric and thematic analysis, this systematic review goes beyond the descriptive literature to propose a design strategy to support decision-making regarding these synergies, addressing the structural and functional contradictions overlooked in the previous literature studies.

Consequently, this study is organized as follows (see Figure 1): Section 2 introduces the data collection process and the bibliometric analysis for the existing literature, and investigates the chosen studies related to the research topic. Then, Section 3 discusses the current state of knowledge from the previously analyzed literature, identifies gaps in the existing knowledge and emerging interdisciplinary trends, and offers insights for future research direction. Afterwards, Section 4 outlines the proposed design strategy for generating VGS-AFT hybrid façades through four phases, including conceptualization, hybridization, optimization, and development. Finally, Section 5 presents the challenges and limitations of the current study. Furthermore, the conclusions and recommendations for future studies are presented in Section 6.

2. Materials and Methods

To map, analyze, and synthesize existing research on VGS integration methodologies, this systematic review was conducted in accordance with the updated PRISMA 2020 guidelines [20]. The review protocol was not formally recorded in a public database but was developed internally to ensure a systematic approach to data collection and analysis.

Accordingly, this study adopted a mixed-method approach: (1) quantitative bibliometric analysis following PRISMA 2020 guidelines for data collection, employing the Bibliometrix package in RStudio software version 4.5.2 to identify and classify publication trends in the VGS integration methodologies; and (2) qualitative thematic analysis, referencing specific studies relevant to the research scope to conduct a more in-depth investigation of how they address the integration methodological trends through data synthesis from the most relevant studies. To achieve the main study objective of improving VGS performance through integration with systems of AFT, this study was conducted to identify: (a) key findings of the relevant literature and common practices; (b) gaps in the current research knowledge; and (c) future research directions. Based on these findings, a design strategy for generating VGS-AFT hybrid façades will be proposed, offering practical recommendations for architects and engineers. In accordance with the adopted methodological framework, shown in Figure 2, this study was implemented in three successive phases: (a) data collection: PRISMA flowchart; (b) data analysis: bibliometric analysis; and (c) data synthesis: investigation of relevant studies.

2.1. Data Collection: PRISMA Flowchart

A preliminary search was conducted in the Scopus and Web of Science databases, recognized as the most comprehensive databases for high-impact peer-reviewed literature in architectural technology and environmental science, for documents concerning “vertical greenery systems”, in addition to scoped keywords related to “advanced façade technologies”. The systematic search was conducted using the following Boolean string: ((“vertical green*” OR “living wall*” OR “green façade*” OR “green wall*” OR “vertical garden*” OR “façade-integrated vegetation*” OR “building-integrated vegetation*”) AND (“advanced façade*” OR “façade technology*” OR “smart façade*” OR “high performance façade*” OR “adaptive façade*” OR “energy generating façade*” OR “ventilated façade*” OR “bioactive façade*” OR “algae*” OR “parametric*” OR “double skin*” OR “kinetic*” OR “dynamic*” OR “intelligent envelope*” OR “photovoltaic*” OR “solar*” OR “biomimicry*” OR “phase change material*” OR “smart material*” OR “glaze*” OR “curtain wall*” OR “integrated*” OR “integration*”)).

This systematic search of titles, abstracts, and authors’ keywords yielded 1120 preliminary results as of 1 January 2026. To ensure accuracy despite the use of broad Boolean terms (such as “solar,” “parametric,” “dynamic,” or “integration”) to ensure a high recall rate, a five-step filtering process was applied, as summarized in

Table 1. The inclusion and exclusion criteria for the systematic review through a five-step filtering process.

Criterion	Inclusion Criteria	Exclusion Criteria	Documents Number
1. Search Period	Publications from the past decade (2015 to early 2026) will ensure subject-specific relevance.	Articles published before 2015.	This step reduced the dataset from 1120 to 979 documents.
2. Subject Area	Publications were limited to fields directly related to the study, including architecture, engineering, energy, building technology, and environmental sciences.	Fields unrelated to the building envelope or building greening.	This step narrows the dataset to 844 documents.
3. Document Type	Peer-reviewed scholarly output: articles, reviews, conference papers, and book chapters.	Non-scholarly, unindexed, or superficial content (editorials, errors, letters, notes).	This criterion assured academic reliability and resulted in 814 documents.
4. Language	Documents published in English, which is the universal scientific language.	Documents in any language other than English.	The number of recorded documents decreased to 799.
5. Keyword Relevance	A keyword-based filter was applied to identify relevant topics from titles and abstracts of terms like “green wall,” “green façade,” “green building,” “vegetation,” “green infrastructure,” “nature-based solution,” “vertical greening,” “built environment,” “vertical gardens,” “wall systems,” and “urban green”.	Documents that are missing from the core keywords related to both NbSs and AFTs. Documents using terms like “solar,” “parametric,” “dynamic,” and “integration” in contexts unrelated to the greenery elements’ synergies.	This final step retrieved an enhanced dataset of 583 documents.

and Figure 3, in accordance with the PRISMA 2020 flowchart. Generally, documents focusing on irrelevant keywords or standalone technologies without integration with VGS were excluded. This ensured that the extracted documents were directly related to “vertical greenery systems” and addressed the topics, issues, and challenges specific to this field, in line with this study’s objective.

After removing 168 duplicate documents from the 583 documents resulting from the screening process in Table 1, a total of 415 documents were identified and included in the bibliometric analysis (see Table S1 of the Supplementary Materials for the full list of the studies included). This final dataset is distributed as follows: 299 articles, 60 conference papers, 48 review articles, and 8 book chapters. From this dataset, the latest relevant studies will be deliberately selected for in-depth thematic analysis (in Section 2.3) based on their direct relevance to VGS-AFT hybrid façade performance.

2.2. Data Analysis: Bibliometric Analysis

Once the data collection process was completed, the selected documents were saved in a BibTeX file and then prepared for bibliometric analysis using the Biblioshiny 5.0 online tool, which utilizes the bibliometrix package in RStudio software. Bibliometrix, a package in RStudio, an open source software, provides a set of tools for conducting quantitative bibliometric research and science mapping analysis of scientific literature [21,22]. The collected data were analyzed in terms of (1) publication trends, (2) co-occurrence, and (3) co-citation as follows.

2.2.1. Publication Trends Analysis

The literature on VGS integration has grown substantially over the past decade. Figure 4 illustrates the analysis of annual scientific production from 2015 to 2026, revealing a significant expansion in research interest over the past decade. Between 2015 and 2020, the field maintained a modest output, characterized by slight fluctuations and a baseline of approximately 14 articles. A pivotal shift occurred in 2021, initiating a sustained acceleration phase known as the “peak of publications” period (2021–2025).

This acceleration reached its historical peak in 2025, with 68 articles, representing an almost fivefold increase compared to the first year of the study. This surge underscores the topic’s growing contemporary relevance and increasing academic interest. While the 2026 data show a sharp decline, this is attributed to a temporal artifact caused by incomplete data indexing for that year. This substantial growth in the recent literature necessitates this systematic review to synthesize the available evidence and identify emerging research frontiers.

2.2.2. Co-Occurrence Analysis

Keyword-based networks provide a comprehensive understanding of the search domain, offering insights into the interrelationships between search topics and subtopics within that domain. As a result, a bibliometric analysis of VGS integration as a trending topic was conducted using RStudio, based on a co-occurrence analysis type, where “all keywords” was used as the unit of analysis for searches originating from the database. Keywords were limited to the most common and relevant keywords.

The analysis reveals three main clusters, as shown in Figure 5, each of which represents a distinct thematic area that links VGSs to building performance. From Figure 5, it can be observed that the largest cluster in terms of word counts is the green cluster with 19 words, characterized by terms such as “green wall”, “vegetation”, “energy efficiency”, and “sustainability”, which represents a more ecologically driven research perspective. However, the relatively looser connections between this cluster and the performance-driven clusters indicate a partial disconnect between ecological considerations and AFT system integration. This highlights a potential research gap in exploring the methodology of integrating VGSs with AFT. This is followed by the red cluster, dominated by keywords such as buildings, systems, performance, and energy performance, reflecting a strong emphasis on building-scale performance evaluation. This cluster highlights that the majority of existing studies frame VGS integration primarily as a technical system aimed at improving energy efficiency and overall building performance. The dense interconnections within this cluster indicate a mature and well-established body of research focused on quantifiable performance metrics. In contrast, the blue cluster centers on thermal performance, façade temperature, walls, and living walls, emphasizing the thermal and environmental behavior of façade systems. This cluster illustrates that thermal regulation, heat mitigation, and façade surface temperature reduction constitute core research priorities, particularly in relation to climate-responsive design strategies. The strong links between thermal performance and façade-related keywords suggest that VGSs are predominantly investigated as passive environmental control mechanisms.

Furthermore, the word cloud, a visual version of keyword meta-analysis, is presented in Figure 6 to reflect the most relevant terms depending on the database collected and their keyword frequency. The thematic landscape of the literature centers on the intersection of building performance and environmental sustainability. Dominant terms such as “buildings,” “performance,” and “thermal performance” indicate a shift from qualitative ecological studies toward quantitative, performance-based assessments. The prominence of “green wall,” “facades,” and “vegetation” highlights VGS as the primary focal point for urban intervention. Furthermore, the frequent recurrence of “simulation,” “model,” and “energy savings” suggests that current research is heavily driven by computational modeling aimed at mitigating the “urban heat island” effect and optimizing the building envelope; on the other hand, keywords related to using AFT, such as integration, adaptive systems, energy-generating systems, or high-performance systems, are still less prominent in the thematic landscape of the literature.

2.2.3. Co-Citation Analysis

Co-citation analysis was identified based on the number of the most globally cited publications from the collected dataset, as shown in Figure 7. The top ten most cited articles related to the research topic have also been compiled in

Table 2. Summary of the top ten most cited publications related to the field of vertical greenery systems.

Rank	Document Title	Year	Source	Global Citation	Document Type	Ref.
1st	Vertical greenery systems for energy savings in buildings: A comparative study between green walls and green façades	2017	Building and Environment	343	Article	[24]
2nd	The impact of greening systems on building energy performance: A literature review	2015	Renewable and Sustainable Energy Reviews	321	Review	[17]
3rd	Application of passive wall systems for improving the energy efficiency in buildings: A comprehensive review	2016	Renewable and Sustainable Energy Reviews	249	Review	[18]
4th	Green facade for energy savings in buildings: The influence of leaf area index and facade orientation on the shadow effect	2017	Applied Energy	207	Article	[23]
5th	Green façades to control wall surface temperature in buildings	2018	Building and Environment	157	Article	[30]
6th	Thermal regulation impact of green walls: An experimental and numerical investigation	2017	Applied Energy	154	Article	[25]
7th	Thermal benefits of vertical greening in a high-density city: Case study of Hong Kong	2019	Urban Forestry & Urban Greening	150	Article	[26]
8th	Green Facades and Living Walls—A Review Establishing the Classification of Construction Types and Mapping the Benefits	2019	Sustainability	144	Review	[29]
9th	Thermal behavior of a vertical green facade and its impact on the indoor and outdoor thermal environment	2019	Energy and Buildings	129	Article	[27]
10th	Analysis of thermal effects of vegetated envelopes: Integration of a validated model in a building energy simulation program	2015	Energy and Buildings	110	Article	[28]

, where 70% of these cited publications cover experimental and numerical analysis. The first, second, third, and fourth most cited publications, with 343, 321, 249, and 207 citations, respectively, examined the impact of VGS on the energy efficiency indicator [17,18,23,24]. Meanwhile, the publications ranked in sixth, seventh, ninth, and tenth positions, with 154, 150, 129, and 110 citations, respectively, focused on studying the influence of thermal performance adaptation on VGS [25,26,27,28]. The second, third, and eighth position publications were based on offering a review of implementing VGSs [17,18,29]. On the other hand, the first, fourth, fifth, sixth, seventh, ninth, and tenth positions provided a thorough simulation analysis of the implementation effects of VGSs on environmental performance indicators to enhance surface temperatures, thermal performance, and energy performance [23,24,25,26,27,28,30].

Based on an investigation of the most cited publications, a strong correlation was observed between co-citation analysis and keyword co-occurrence patterns, confirming the thematic consistency of the field. Bibliometric analysis indicates that most studies on VGS primarily focus on simulating energy efficiency and thermal performance, viewing them as passive strategies for improving environmental performance and the resilience of the built environment. However, this focus on performance indicators reveals a relatively narrow research scope, as VGSs are mostly studied in isolation or as complementary elements, rather than as integrated components with AFT systems. Therefore, the bibliometric analysis highlights a gap between performance-oriented simulation studies and the comprehensive integration of VGSs within hybrid facade scenarios. This deficiency underscores the need for in-depth qualitative research to explore how VGSs can be integrated with AFTs in real-world applications, identifying emerging integration strategies, challenges, and design frameworks that go beyond quantitative performance metrics.

2.3. Data Synthesis: Investigation of Relevant Studies

While the bibliometric analysis of 415 studies identified a high-level shift toward systemic performance, it also revealed a deficiency in integrated VGS-AFT terminology. Consequently, the qualitative thematic synthesis was conducted to perform an in-depth manual analysis of the most relevant publications on integrating VGS with AFT to detect the specific technical integration gaps that quantitative software could not identify alone. This analysis summarizes the main findings, methodologies, trends, and research gaps in this field to inform the development of a proposed design strategy. To understand this data synthesis, the characteristics of VGS and classifications of AFT will be discussed below.

2.3.1. Characteristics of Vertical Greenery Systems (VGS)

VGSs are considered an NbS within green infrastructure strategies, since they play a crucial role in sustainability at the building and urban area level, offering multiple environmental and social benefits [31,32,33,34], as follows:

• Reduced Urban Heat Island Effect: VGSs can lower surface temperatures by about 0.5–2.0 °C during heat waves through evapotranspiration and shading, mitigating the urban heat island effect [35,36,37].
• Thermal Regulation: VGSs help regulate indoor and outdoor temperatures, offering thermal comfort. They provide insulation, reducing heat gain during hot weather and heat loss during cold weather [38,39,40].
• Air-Quality Improvement: Vegetation in VGSs filters pollutants from the air, enhancing the overall air quality [9,40]. This benefit is especially valuable in densely populated urban areas [8].
• Energy Efficiency: VGSs can provide thermal insulation, reducing the need for heating, cooling, or artificial lighting [38,39,40,41].
• Biodiversity Enhancement: VGSs provide habitats for various plant species, insects, and birds. They contribute to urban biodiversity and promote ecological balance [10,42].
• Sustainable Water Management: VGSs contribute to stormwater management by absorbing and retaining rainwater, which helps prevent flooding and enhance water quality [43,44].
• Noise Reduction: VGSs act as a sound barrier, absorbing and dampening noise from traffic, construction, and other sources [31,45].
• Enhanced Aesthetics: VGSs add visual appeal to urban environments, creating a sense of nature and well-being [46,47].
• Positive Psychological Effects: Exposure to greenery has been linked to enhanced mental health and reduced stress levels. VGSs can create a calming and soothing atmosphere for building occupants [46,47].

In addition, VGSs can be defined as vegetation forms that grow vertically on the surface of a building’s façade or structure, particularly in areas where traditional horizontal green spaces may be limited, thus contributing to the creation of more sustainable, resilient, and livable cities [5,6,7]. In this context, VGSs can be broadly classified into green façade systems and living wall systems [24,29,31,42,48].

Table 3. Characteristics of the different types of vertical greenery systems, the authors after [24,29,31,42,48].

Main Classification	Description	System Type	Façade Integration	Illustration
Green Façade Systems	Vegetations are rooted directly in the ground or in pots at the base of the wall without the need to add soil on the wall. Plants grow upwards on or around the façade. Supporting structure using stainless steel cables, wire nets, or rigid grids for dense foliage. Irrigation systems are often manual or based on basic drip irrigation at the base. The installation process involves attaching brackets and cables to the wall. The growth rate is slower (plants take time to climb).	Direct Green Façade	Plants are rooted at the ground level and grow directly on the wall surface.
		Indirect Green Façade	Plants climb up on trellises or wire net systems, creating an air gap between the plant layer and the wall.
		Hanging Green Façade	Plants cascade downward from elevated planters at the top of a wall to enhance visibility, ventilation, and air purification.
Living Wall Systems	Vegetations are rooted directly into panel-based systems located on the wall. Plants grow outwards from the surface of the system. A structure supported using welded steel wire panels coated with galvanized powder. The panels contain soil/growing medium integrated within them. Irrigation systems are integrated automated irrigation systems within panels. The installation process includes attaching a heavy-duty support frame to the panels. The growth rate is immediate (pre-planted panels provide immediate cover).	Continuous Living Wall	A continuous layer of growing medium is attached to the wall with a structural support frame. Plants can grow together more naturally.
		Paneled Living Wall	Prefabricated individual panels with built-in growing medium (organic or inorganic substrate) mounted onto a structural support system. Planters can be installed horizontally, vertically, or angled.
		Aeroponic & Hydroponic Living Wall	Plants grow in a nutrient-rich water system without soil, offering lightweight panels and efficient solutions.

summarizes the characteristics and types of these most common systems and their typical integration with façades.

2.3.2. Classification of Advanced Façade Technologies (AFTs)

Based on published research, this section classifies the primary systems of AFTs, indicates their types, and highlights how well they integrate with VGSs. Generally, AFTs can be defined as smart systems, multifunctional materials, or adaptive elements integrated into building façades to effectively respond to external conditions, aiming to enhance energy efficiency, thermal comfort, and sustainability [1,49,50,51]. In this context, the tripartite classification of AFTs, including adaptive, energy-generating, and high-performance façades, is derived from a synthesis of functional objectives identified in the current literature [1,19]. Theoretically, this typology aligns with the performance-based objective, where façades are categorized by their primary contribution to the building envelope: (a) adaptive façades address response to temporal environmental changes [52]; (b) energy-generating façades focus on active resource production [1]; and (c) high-performance façades prioritize passive optimization through advanced material properties [3]. This structure allows for a clear mapping of how VGSs can complement either the movement, the power generation, or the thermal resistance of the envelope. Accordingly, each category is described in

Table 4. Classification of possible advanced façade technologies for integration with vertical greenery systems.

Main Category	Technology Type	Description	VGS Integration	Level of Integration	Illustration	Ref.
Adaptive Façades	Kinetic systems	Responsive or moveable shade elements such as louvers, screens, or blinds that can vary their size, shape, or position in response to environmental stimulation or user input, depending on solar radiation or wind conditions. They can be converted into translational movements like sliding or folding, rotational movements, or combined movements.	(VGS–Kinetic systems) VGS can be mounted on or adjacent to the kinetic elements.	Functional coexistence/structural interdependence		[53,54,55,56]
	Modular systems	A modular façade element designed to facilitate maintenance and improve adaptability through the appropriate integration of factory-manufactured prefabricated units, allowing for rapid and high-quality on-site installation.	(VGS–Modular systems) VGS can be installed within the prefabricated modular units.	Structural interdependence		[57,58,59,60]
Energy-Generating Façades	PV systems	PV panels can be integrated as shading devices into building components exposed to direct sunlight, such as roofs, façades, and windows, resulting in an active façade. These panels can be fixed or movable and equipped with sensors, motors, and control systems.	(VGS–PV systems) VGSs are always placed separately under PV panels on the same layer or on separate layers for reasons of accessibility and operational safety.	Technological synergy		[61,62,63,64,65,66,67]
	Bioactive systems	Incorporating living creatures, such as algae, between two vertical or horizontal panels for CO2 absorption and biofuel production to enhance cooling effects while producing biomass.	(VGS–Bioactive systems) VGS can be installed outside or adjacent to a microalgae-filled façade.	Functional coexistence		[55,68,69]
High-Performance Façades	DS systems	These systems depend on the idea of integrating an air cavity to enhance ventilation and indoor climate control between an internal layer, usually an opaque or glazing layer, and an external layer, usually a perforated panel or glazing layer.	(VGS–DS systems) VGS can be installed on the inner layer, placed in the middle as a buffer zone, or on the outer layer of the building.	Structural interdependence		[70,71,72,73]
	Glazing systems	Integrating VGSs as shading elements on glass panels provides aesthetics, natural lighting, and critical energy efficiency through heat and light control, as well as thermal insulation for comfort and sustainability. These systems include types such as curtain walls, structural glazing, and operable windows.	(VGS–Glazing systems) VGS can be positioned adjacent to or outside the glazing system.	Functional coexistence		[74,75,76,77]

regarding its types, possible integration scenarios with VGSs, stating the thematic code for this integration, and hybridization integration levels, classified as follows: (a) functional coexistence: where systems are physically adjacent but lack operational links; (b) technological synergy: where systems are operationally linked to increase their efficiency; or (c) structural interdependence: where systems share a common framework, as an integral part of the mechanical or structural composition of the façade [1,49,50,51].

2.3.3. Investigations of Relevant Studies Related to Research Scope

After reviewing the collected document abstracts, the selected documents focused on clearly addressing VGS-AFT hybrid façade scenarios and demonstrating integration, even if the integration was not complete or technically successful. Any shortcomings in integration will be discussed in more detail later in the Results and Discussion (Section 3). Accordingly,

Table 5. The latest top ten relevant studies addressed the integration of VGS-AFT hybrid façades.

Ref.	Year	Study Objectives	Integration Scenario	Integration Class.	Performance Indicators	Study Methods	Key Findings	Quality Checklist
[67]	2026	Exploring the effects of PV shading on the photosynthetically active radiation on the vegetation surfaces of a green wall.	PV panels parallel to an indirect green façade	VGS–PV systems	Solar radiation Photosynthetically active radiation	Experimental and simulation study	The wall should not be covered with PV panels and plants; rather, it should be tailored to the plants’ light needs with the specific shade patterns created by the PV array.	High: combines real-world experiments and simulations for validation.
[61]	2026	Discussing key influencing factors such as the distance between PV and greenery, plant species, and climate zones.	Façade-integrated PV with indirect green façade as vertical greenery (FIPV-VG)	VGS–PV systems	Surface temperature Energy efficiency	Review study	Integrating PV with greenery improves solar efficiency by cooling the panels through evapotranspiration, with FIPV-VG achieving temperature drops up to 4 °C and green roofs up to 11 °C.	Moderate: comprehensive synthesis of factors but lacks primary experimental data or new experimental tests.
[76]	2025	Investigating the impact of VGSs on building energy efficiency through glazed façade opening under various window-to-wall ratios (WWRs).	Indirect green façades on glazed windows	VGS–Glazing systems	Energy efficiency Cooling and heating loads	Numerical simulation study	VGSs can reduce annual building energy consumption by up to 25.87%, with deciduous plants outperforming evergreen varieties, especially in buildings with high WWR.	Moderate: strong predictive modeling, but it oversimplifies greenery as a static shade coefficient without considering biological growth variables.
[78]	2025	Combining PV technology with VGSs for bifacial PV green façade (BPVGF), investigating thermal environment regulation, and its effect on energy production.	Bifacial PV panels perpendicular to an indirect green façade	VGS–PV systems	Thermal performance Energy efficiency	Experimental study	BPVGF improves building thermal comfort by reducing indoor temperatures by up to 3.33 °C and cooling the PV modules due to the presence of greenery.	High: provides direct experimental evidence of biological and mechanical synergies.
[79]	2025	Presenting an innovative environmental air purification system using renewable energy to achieve energy self-sufficiency.	Double-skin façade (DSF) with internal paneled living wall and external moving PV trackers	VGS–PV–DS systems	Energy efficiency Air purification	Experimental study	The system’s integrated solar trackers generated enough power to cover 76.3% of its operational needs during winter testing.	High: focuses on practical applications and air purification metrics.
[64]	2025	Combining an adjustable PV blind system with a green façade (APVGF) provides building energy savings.	An adjustable PV panel parallel to an indirect green façade	VGS–PV systems	Daytime temperature Interior air temperature Interior light intensity Daily power generation	Experimental study	The APVGF system adjusts the PV angle based on the sun’s position to enhance PV efficiency and the building’s aesthetic value.	High: includes a comparative analysis of fixed and adjustable systems.
[80]	2025	Reporting the annual performance of a green DSF in a university building in Shanghai, based on long-term site monitoring.	DSF with external indirect green façade	VGS–DS systems	Thermal performance Energy efficiency	Experimental and simulation study	The impact of VGS heating/cooling adds to a better understanding of the VGS’s annual thermal performance.	Advanced: incorporates long-term site monitoring (one year) and simulation for seasonal validation.
[81]	2025	Developing a computational fluid dynamics (CFD) model of the BPVGF to evaluate its thermal performance.	Bifacial PV panels perpendicular to an indirect green façade	VGS–PV systems	Thermal performance	Numerical simulation study	Highlighting the dual potential of vertical greening in optimizing thermal performance and improving PV conversion, a 2.5% efficiency increase is achieved.	Moderate: utilizes CFD modeling but lacks practical validation of the projected efficiency increase.
[63]	2025	Integrating thin-film PV and hydroponic urban farming systems to evaluate a modular agrivoltaics building envelope	Modular PV panels with horizontal paneled living walls arranged in a checkerboard pattern	VGS–PV systemsVGS–Modular systems	Energy efficiency Light Water Structure	3D simulation study	Providing a practical framework for future applications in urban sustainability by addressing space optimization and multifunctionality.	Moderate: strong theoretical framework for improving space utilization, but it does not include long-term maintenance or monitoring of structural loads.
[53]	2024	Proposing an optimization scheme for dynamic living plant walls (DLWS)	Paneled living walls on dynamic shading devices	VGS–Kinetic systems	Indoor thermal temperature	Experimental study	Verifying the performance advantages and feasibility of integrating DLWS into practice, reducing the average indoor temperature by 3.6 °C during the daytime.	High: validated the feasibility and performance advantages of kinetic integration through practical testing.

provides an overview of the top ten recent studies on these topics, listed in descending order of publication year. The studies included were analyzed based on their objectives, the integration scenario used for the hybrid façade, the thematic code for the integration classification, the performance indicators targeted for evaluation, the study methodology type, and the key findings, in addition to the study evaluation based on the quality checklist rating “of low, moderate, high, or advanced”, assessed based on three pillars: (1) methodology accuracy (use of validated software or real-world sensors), (2) validation techniques (comparison of simulation vs. experimental data), and (3) comprehensiveness of performance indicators that were addressed.

In general, the studies in Table 5 highlighted the advantages of integrating VGSs with AFTs, particularly in VGS–PV systems, to generate hybrid façades that contribute to improving the overall performance of the building, with an emphasis on enhancing thermal performance and energy efficiency.

Despite these findings, further research is needed to investigate alternative VGS-AFT integration scenarios and their effects on energy efficiency and thermal performance. Furthermore, the optimization of design parameters under various micro-climatic conditions for different building configurations, as well as their environmental performance influence on daylighting, visual comfort, air quality, and acoustic comfort, has not yet been investigated. Moreover, this investigation highlighted that, although many studies provide reliable thermal data, there is a lack of standardized integration procedures and long-term lifecycle assessments (LCAs) in this field. Such research gaps can be addressed by experimental investigations or simulation-based analysis, which will provide significant direction to engineers and architects looking for better hybrid façade solutions.

3. Results and Discussion

This section presents and discusses the results of the adopted methodology, highlighting (1) the key findings and common practices of bibliometric analysis and research on VGS-AFT integration; (2) identified gaps in the current research knowledge; and (3) research directions for future studies. Based on this, a design strategy will be proposed for the fundamental principles of generating these hybrid façades. Finally, the challenges and limitations encountered in this study will be outlined.

3.1. Key Findings Based on Current Research Knowledge

This study conducted a systematic analysis of 415 publications and reveals that adopting VGS represents a sustainable building technique for enhancing overall building performance and environmental sustainability.

3.1.1. Thematic Evolution and Global Trends

Figure 8 presents a thematic map resulting from bibliometric analysis, grouping clusters associated with distinct research sub-topics. This map facilitates the assessment of each topic in terms of centrality and maturity, identifying established, emerging, and declining areas. The four quadrants of the thematic map (niche themes, emerging or declining themes, motor themes, and basic themes) can easily plot and group the keywords to identify research themes. The keywords “green wall”, “structural wall, and “energy efficiency” were presented as niche themes, which offer potential topics in need of future study. Nevertheless, the keywords “green building” and “residential building” were presented as emerging, despite their importance. In contrast, the keywords “vegetation”, “green wall”, “urban heat island”, and “thermal comfort” were considered motor themes, which reflect developed and important themes. In contrast, the keywords “buildings”, “performance”, and “systems” reflected basic themes.

Accordingly, the thematic analysis indicates that, while the impact of vegetation remains a mature motor theme, the core of the research, “building performance systems,” remains a basic theme with significant space for technological development. Furthermore, the classification of energy efficiency as a niche theme highlights a critical gap: the industry possesses technical data but lacks the necessary integration to make it a standard motor for all architectural projects. Similarly, the absence of specific bubbles for AFT systems confirms that these integrative systems are currently in the “frontier” of the field, given their novelty and lack of centrality, although they are essential for future trends.

Thematic evolution (Figure 9) illustrates a chronological roadmap of how the intellectual focus in the field of VGS has shifted from broad, fundamental concepts to a specialized integration approach. By analyzing the shifts across three time periods (2015–2020, 2021–2023, and 2024–2026), a clear trajectory toward “systemic performance” is observed. While “buildings” was the overarching theme in the first period (2015–2020), the “vegetation” and “green wall” clusters show consistent flows across the three periods.

Surprisingly, the period 2024–2026 indicates a decisive shift toward “performance,” “systems,” and “façades.” The integration of previous general themes into these technical clusters underscores a radical shift toward integrated building envelopes. This evolution directly necessitates the development of a design strategy (proposed in Section 4) to manage the increasing complexity of the VGS-AFT hybrid façades.

Furthermore, a thematic and bibliometric analysis, illustrated by a three-field diagram (see Figure 10), shows that keyword analysis identifies “buildings,” “performance,” and “vegetation” as key conceptual pillars, reflecting a shift toward quantitative assessments of the building envelope. This engineering focus is mirrored in the publishing environment, where high-impact journals such as Building and Environment, Energy and Buildings, and Sustainability are the primary outlets for studies on energy performance and facade systems.

Geographically, this field is dominated by Chinese research output, although significant contributions from Italy, Spain, and Australia highlight a global consensus on the importance of vegetation in mitigating urban heat island effects in humid subtropical and Mediterranean climates. The low frequency of use of terms like “simulation” and “model” suggests that this discipline requires the application of predictive computational tools to optimize energy efficiency. In this context, these data demonstrate a highly active global research field that prioritizes integrating NbSs into the built environment to enhance sustainable development and climate change resilience. Despite these findings, research remains scarce regarding hot–arid climates where heat is extreme and humidity is low, as well as the temperate and cold climates. To fully evaluate the adaptability of these systems, future investigations must prioritize these specific environmental conditions.

In this context, it is clear that broad performance metrics dominate the current global discourse. Energy performance and thermal performance were among the most extensively studied indicators, with a focus on how technologies integrated with VGSs affect temperature, cooling, and heating loads [24,25,26,27,30]. However, the lack of direct links between VGSs and specific AFT systems indicates that the currently published studies are fragmented, regardless of the significant benefits of such an integration approach [56,82]. Thus, this study fills a crucial gap by integrating this disparate performance data into a unified hybrid framework.

3.1.2. Performance of Hybrid Façade Scenarios

One of the most promising areas of research is the synergistic integration of VGS–PV systems, which represents a significant integration of VGSs with energy-generating façades. This is followed by the utilization of VGS–DS systems as a promising integration of high-performance façades. In this context, studies conducted on the integrated hybrid façades of VGS–PV systems show that carefully designed systems can provide multiple services simultaneously, such as power generation, food production, thermal regulation, and environmental benefits, while managing trade-offs through optimization [65,72,83]. In this context, the investigated key innovative hybrid façade scenarios and their implications will be discussed below:

A.

Adaptive Façade Integration:

• VGS–Kinetic Systems: These systems utilize movable shading devices, such as DLWS, which have been primarily studied for their role in regulating summer heat, and have a better cooling effect compared to dynamic shading sails without VGSs. Experimental studies by Wang et al. and Bao et al. have demonstrated that adjusting the angle of the plant wall according to the sun’s position can reduce the internal temperature by approximately 2.7 °C in a humid subtropical climate in China [53,60]. On the other hand, Seyrek et al. discussed the parameters related to sustainability in the preliminary design phase for generating VGS–kinetic systems and the evaluation of decision support tools [56]. While these studies confirm the effectiveness of these systems in reducing heat, they also highlight a significant technical gap. Given the limited research on the impact of continuous mechanical movement on plant physiology and root stability, as well as the challenges of maintaining irrigation lines across movable joints, further research is required.
• VGS–Modular Systems: Adaptive VGS–modular systems represent an advanced category designed to respond to changing environmental conditions and building needs for construction efficiency, quality control, and easy replaceability [84]. These cases involve 3D-printed or prefabricated units designed for rapid on-site installation, based on experiment-driven optimization, often tested for their ability to reduce solar heat gain [85]. An analytical evaluation conducted by Azkorra-Larrinaga, Romero-Anton et al. in temperate climates has shown that modular living walls can reduce solar heat loads by 46% to 67% compared to regular untreated walls [58]. However, a major shortcoming of the current research is the underestimation of structural load challenges for modular systems. Most studies focus on the efficiency of the modular unit but ignore the high capital costs and extensive structural reinforcement required when implementing these systems as retrofits to existing building envelopes, which requires further investigations [59,86,87].

B.

Energy-Generating Façade Integration:

• VGS–PV Systems: This hybrid scenario is the most researched and is typically studied in subtropical and hot, humid climates, such as those found in China and Spain, to mitigate cooling loads. Studies on multifunctional agrivoltaics building envelope (ABE) systems and APVGF have found that vegetation placed as a green buffer space between a standard interior façade and an external PV system can cool these panels by 1 °C to 4 °C, with peak performance occurring when outdoor temperatures exceed 20 °C [88]. In the hot summer conditions of humid subtropical climates, these systems reduce wall temperatures by an average of 21.4 °C, with peaks of up to 30 °C, while providing a warming effect of about 3 °C during the winter when outside temperatures drop below 0 °C [78,89]. Additionally, when APVGF was placed on window glass in the same climate, it significantly improved building efficiency and comfort by reducing indoor temperatures by up to 18.6 °C and increasing daily power generation, outperforming fixed 30° and 90° angles by 17.2% and 22.5%, respectively, through an automated sun-tracking PV blind system integrated with natural greenery [64]. However, this recent research highlights a critical design challenge in the same humid subtropical climate: PV panels on facades create a “spatial heterogeneity” in light distribution, significantly reducing the light available to plants underneath them to as low as 225.6 W/m² compared to 371.9 W/m² in unshaded areas [67]. On the other hand, CFD modeling of the BPVGF, conducted in Shenzhen, indicates that an 80 mm vegetation thickness provides optimal double benefits by reducing outer wall temperatures by 5.29 °C and bifacial PV panel temperatures by 4.72 °C, which in turn increases solar-to-electricity conversion efficiency by 2.5% [81]. Furthermore, a study introduces a smart, zero-energy green DSF that utilizes solar-tracking PV panels to achieve energy self-sufficiency while significantly purifying indoor air, with specific plants like the Spider Plant, reducing pollutants by up to 60% within 80 min [79]. Such a case study is suited for buildings that do not require structural adjustments and can be widely implemented in metropolitan areas to increase urban green space [79]. Additionally, a review study by Tao and Xiang recommended that the optimal distance between PV panels and VGS requires further in-depth research, as it significantly affects both convection heat transfer and latent heat transfer [61]. Despite the data on increased efficiency, there is a notable lack of long-term LCAs. The current research prioritizes immediate thermal optimization but neglects the space requirement for such systems on the facade, as these two systems often compete for space on vertical façades where foliage may eventually shade the PV panels, reducing the energy gains the system is designed to achieve [79].
• VGS–Bioactive Systems: A review study was carried out by Oncel and Senyay Oncel about integrating microalgae with VGS for CO² capture and biomass production [68]. However, research in this area remains largely theoretical or limited to review studies. There is a notable lack of experimental data on the biological symbiosis between higher green plants and algae, leaving the actual environmental performance of these biological hybrid façades unverified in real-world urban contexts [55,69].

C.

High-Performance Façade Integration:

• VGS–DS systems: Integrating vegetation of a green façade within or in front of a DSF to provide a VGS–DS system has demonstrated energy savings of up to 16% for cooling energy consumption, with additional reductions in internal temperature by 3.7 °C compared to a regular DSF in an office building of a university campus in Shanghai, offering improved thermal performance [70]. Furthermore, a long-term field measurement carried out by Jiang and colleagues contributed to a more comprehensive understanding of the annual thermal performance of the VGS–DS system conducted in Shanghai’s humid subtropical climate [80]. This study’s findings indicate that, while the VGS–DS system provides cooling for about two-thirds of the year with an average exterior wall cooling of 1.6 °C, the south-facing orientation achieved higher annual energy savings of 10.2 kWh/m² compared to 4.5 kWh/m² for the north-facing orientation. On the other hand, an investigation conducted on the VGS–DS system, also in Shanghai, revealed that the system significantly improves thermal performance, resulting in a refinement in average internal operating temperature of 1.1 °C (maximum 2.7 °C) for south-facing offices and 0.6 °C (maximum 1.9 °C) for north-facing offices [73]. While thermal performance is well documented, there is a gap highlighted in evaluating how the dense vegetation within a buffer zone affects humidity levels, moisture-related decay in the cavity, and acoustic performance, which requires further experimentation.
• VGS–Glazing Systems: These integrated systems can provide enhanced daylight control through combined plant and glass modulation, improved acoustic insulation, reduced glare while maintaining views, and synergistic thermal performance [90,91,92]. Using EnergyPlus 9.4 software, a dynamic simulation study combined with real-world experimental data in Guangzhou demonstrated that placing a VGS in front of glass windows significantly reduces cooling loads during the summer months, with energy savings ranging from 15.49% to 33.32%, depending on the type of vegetation and the WWR [76]. These results confirm that the VGS is an effective strategy for improving energy efficiency, particularly in buildings with high WWRs, which should be considered as a fundamental VGS–glazing system solution in sustainable building design [75,76,92]. A major gap in these studies is the oversimplification of the biological shade criteria of greenery. Most of the literature treats greenery as a static shade coefficient, ignoring the dynamic, unpredictable nature of plant growth, which can lead to issues with flickering, glare, and obstructed views that significantly impact occupant visual comfort. Future research should use high-dynamic-range (HDR) imagery to assess the subjective occupant experience in VGS–glazing system scenarios.

Overall, the performance of hybrid façade scenarios demonstrates a significant shift from treating VGSs as mere aesthetic additions to integrating them as effective and sustainable building components. This study concluded that, while thermal benefits have been proven across various climates, the industry lacks the standardized integration strategy necessary to transition these hybrid scenarios from experimental models to established architectural standards. In this context, Figure 11 provides a primary visual bridge between the key findings of the bibliometric and thematic analysis in terms of common practices, key gaps, and future directions that will guide the proposed design strategy.

3.2. Identified Research Gaps

This study revealed important findings, indicating a focus on a growing architectural interest in improving building performance in conjunction with developing hybrid façade scenarios; however, a significant gap remains in methodological development, as there is a lack of standardized integration workflows between VGSs and AFT systems. Accordingly, based on a systematic analysis of previous research, the resulting gaps in the quality of current research can be assessed through five main points:

• Studies validation gaps: High-quality studies are characterized by their use of simulation for prediction and experimentation for validation. However, many studies rely solely on numerical simulations, which may not account for the unpredictable nature of plant development, leading to potential discrepancies in visual comfort and glare results.
• Limited examination of hybrid façade scenarios: This analysis identifies a significant gap in the research of integrating VGSs with other AFT systems, rather than VGS–PV and VGS–DS systems, such as VGS–kinetic systems, VGS–modular systems, VGS–bioactive systems, and VGS–glazing systems. Thus, keyword frequency analysis and clustering analysis confirm this deficiency, as terminology related to AFT, such as integration, adaptive façades, energy-generating façades, or high-performance façades, is still rare and less discussed in the research. Furthermore, the heavy emphasis on “building performance”, as evidenced by the high-frequency terminology, neglects examining diverse building configurations and climatic context.
• Narrow scope of measurements: Most studies focus almost exclusively on measuring thermal performance and energy efficiency. Consequently, a significant qualitative gap can be identified regarding the measurement of other environmental indicators, such as daylighting, visual comfort, air quality, and acoustic comfort, as well as the challenges of identifying the suitable irrigation system characteristics, structural loads, capital costs, and maintenance requirements, which are rarely quantified in the current studies [3,51,91]. Current research lacks a standardized “Climatic Sensitivity Index” to quantify these variations across different Köppen climate classifications. In addition, most measurements in the studies conducted were taken in humid subtropical climates; there is a significant lack of measurements in other climatic contexts, such as hot, dry, temperate, or cold climates.
• Monitoring constraints: While a few studies utilize long-term monitoring, a significant portion of the research relies on short-term summer snapshots [80]. However, without long-term monitoring and LCAs, the true sustainability of these hybrid façades remains unclear, particularly concerning moisture-related damage or mechanical corrosion, as is the case with VGS–kinetic systems and VGS–bioactive systems [53,60,93].
• Lack of involvement of smart technologies: The findings reveal a need for parametric optimization, artificial intelligence (AI), and machine learning to simulate, optimize, and re-evaluate the performance of VGS-AFT hybrid façades, indicating a new research frontier that still lacks a solid foundation [31,51,72,91].

Thus, while the study partially fills previous disciplinary gaps, it highlights a new set of areas that have not been adequately explored in scientific research and applied studies.

3.3. Future Research Directions

Based on identified gaps and emerging trends, the following research directions are prioritized:

• Improving decision-making in VGS-AFT applications: Future research should prioritize the transition from “feasibility simulations” to experimental investigations of the proposed strategy (in Section 4). Specifically, creating full-scale physical prototypes is necessary to test the technical detailing in Phase 3, such as the structural load management and irrigation integrity of moving parts in kinetic hybrid façades. Developing standardized monitoring metrics through IoT sensors will allow researchers to validate conceptual performance outcomes against real-world data over the long term.
• Examining different hybrid façades scenarios: Evaluating multiple hybrid façades resulting from the integration of VGSs with different AFTs (VGS–kinetic systems, VGS–modular systems, VGS–bioactive systems, and VGS–glazing systems) through simulation-based analysis and experimental investigations for validation.
• Testing other renewable energy systems: Besides PV systems, other renewable energy systems can be tested, such as building-integrated wind power and thermoelectric power.
• Measuring other performance indicators: Investigating environmental indicators, especially for VGS–PV and VGS–DS systems, such as daylighting, visual comfort, air quality, and acoustic comfort, using multi-criteria evaluations, in addition to testing different irrigation system characteristics and measuring the requirements for the structural loads, capital costs, and maintenance. To manage these competing variables, future research must transition from “feasibility” to “dynamic control”.
• Developing standardized monitoring metrics: Defining methodologies for testing the performance of hybrid façades and creating long-term monitoring programs and LCAs that have been tested for different types of buildings and across multiple climatic zones, such as hot–arid, temperate, or cold climates.
• Utilizing emerging smart technologies: IoT sensors, AI-driven irrigation, wastewater management, and digital fabrication and construction automation.
• Using advanced optimization algorithms: Genetic algorithms, multi-objective evolutionary algorithms, and machine learning-based optimization to generate these hybrid façades and identify optimal alternatives.

4. Design Strategy: Possibilities of Generating Hybrid Façades

Integrating VGSs with AFTs yields VGS-AFT hybrid façades, a solution that necessitates studying the configuration parameters influencing the performance of these systems to emphasize the synergy between biological and mechanical systems. Accordingly, to address the lack of standardized procedures identified in keyword co-occurrence and thematic evolution maps, this study proposes a four-phase design strategy to identify and classify the potential for creating these hybrid façades applicable to various building types. This roadmap translates the fragmented evidence found in bibliometric clusters and the combined results of thematic analysis into a structured decision-making tool, enabling engineers to identify areas requiring further practical applications.

4.1. A Four-Phase Design Strategy for Hybrid Façades

To operationalize the findings of this study, Figure 12 provides a visual synthesis of the proposed design strategy. The following subsections detail the generation logic required to navigate the four phases, conceptualization, hybridization, optimization, and development, concerning integrated VGS and AFT frameworks [9,56,82,83].

• Phase 1: Conceptualization—Pre-designing the VGS-AFT synergy through contextual analysis and the identification of complementary goals

This initial phase focuses on identifying the basic requirements that will control the design process for a hybrid façade approach, ensuring an alignment with the environmental constraints and sustainability goals.

• Climate and Urban Feasibility Analysis: Designers must evaluate site-specific factors such as solar radiation, wind patterns, and temperature extremes to determine which system of VGS and AFT best complements the local climate.
• Building Typology Analysis: Designers must estimate the morphology of the investigated building in terms of function (residential, commercial, etc.), form (shape, structure, layout), size, height, capacity, and style to help in defining the targeted performance.
• Performance Objective Definition: This step defines multi-criteria targets, whether it is environment-based, including thermal regulation, energy generation, or acoustic comfort, functional-based, including user comfort and utility such as providing shading or acting as a buffer zone, and/or aesthetic-based, for visual impact, ensuring that the biological (VGS) and mechanical (AFT) systems work toward shared sustainability goals.
• Bio-Mechanical VGS Selection: Selecting the appropriate VGS type (direct, indirect, or hanging green façade, or continuous, paneled, or hydroponic living wall) is based on its structural and functional compatibility with the intended AFT system.

2.

Phase 2: Hybridization—Simulation of VGS-AFT hybrid configurations using parametric design and generative modeling

This phase uses computational tools to explore how VGSs and AFTs can be functionally combined into a singular, active unit.

• Conceptual AFT-VGS Integration: Based on the researched scenarios, designers select a primary system, such as a kinetic, modular, PV, bioactive, DS, or glazing system, to integrate with the greenery, according to the targeted levels of hybrid integration, including functional coexistence, technological synergy, or structural interdependence.
• Generative Modeling of Hybrid Façades Alternatives: Designers create numerous design iterations that explore the physical relationship between plants and the integrated system, such as the distance between PV panels and foliage to manage heat transfer to achieve Phase 1 objectives.
• Performance Simulation Analysis: Computational analysis predicts the combined efficiency of the hybrid façade scenario, evaluating how the vegetation’s shading and transpiration affect the operating efficiency of the modeled AFT system components.

3.

Phase 3: Optimization—multi-objective optimization of VGS-AFT scenarios through iterative performance refinement and technical detailing

This phase refines the most promising hybrid façade alternative through an iterative process, balancing the physiological needs of the plants with the mechanical performance of the AFT systems.

• Multi-Criteria Optimization (MCO) of Hybrid Façade Metrics: Using iterative simulation, designers find the optimal scenario where the efficiency of the conducted AFT system and plant health from the conducted VGS are both maximized without trade-offs.
• Bio-Technical Prototyping and Feasibility: Prototyping is used to test real-life structural loads and the physical integration of biological and mechanical elements.
• VGS-AFT Technical Detailing: This step focuses on the co-location of technical systems, including integrated irrigation, smart sensors, and anchoring mechanisms that support both the greenery and the AFT hardware.

4.

Phase 4: Development—Operational management through monitoring and controlling the implementation of the VGS-AFT hybrid façade lifecycle and adaptive maintenance

The final phase focuses on the long-term performance and physical deployment of the optimal hybrid façade scenario across its lifecycle, shifting from static installation to adaptive management.

• Lifecycle-Responsive Integration: Decision-making here determines if the hybrid façade system is a lightweight retrofit for an existing building or a structural integration for a new building, accounting for additional structural loads.
• Coordinated Hybrid Implementation: The installation process requires multidisciplinary coordination between traditional façade engineers and horticultural specialists to ensure that both VGS-AFT systems are commissioned correctly.
• Post-Occupancy Evaluation (POE): Using IoT sensors, the façade’s performance is monitored for energy consumption, indoor comfort, and plant vitality simultaneously.
• Adaptive Bio-Mechanical Maintenance: Long-term sustainability is managed through data-driven adjustments, where irrigation and AFT settings are adapted based on real-time plant growth and climatic shifts.

Lastly, if the desired objectives are not achieved, the process can be repeated to choose a different path or add another AFT system that improves the outcomes.

4.2. Decision-Making Tool for Hybrid Façades

To operate the proposed design strategy,

Table 6. Operational decision-making matrix for VGS-AFT strategic integration.

AFT System	Recommended VGS Type	Compatibility & Research Maturity	Primary Integration Objective (Phase 1)	Modeling & Simulation (Phase 2)	Key Optimization Variable (Phase 3)	Lifecycle & Maintenance Focus (Phase 4)
Kinetic Systems	Indirect green façades (mounted on) Paneled living wall (mounted on, adjacent) General VGS (internal)	Moderate/Emerging	Dynamic shading; indoor temp/humidity regulation.	The physical relationship between movable shading devices and plant root stability.	Movable joints; mechanical movement vs. plant stability.	AI-driven solar tracking; real-time plant health and solar angle adjustments.
Modular Systems	Paneled living walls (prefabricated)	Moderate/Challenging	High construction efficiency; factory-controlled quality.	Parametric exploration of factory-manufactured units.	Structural load assessment; reinforcement detailing.	LCA to manage the cost-complexity of unit replacement.
PV Systems	Paneled living walls (adjacent) General VGS (internal)	High/Synergistic	Dual energy generation, thermal regulation, and management of space competition.	The efficiency of the placement of PV panels and foliage.	Distance between PV and plants to maximize heat transfer and energy efficiency.	Smart sensors for real-time energy production and adaptive irrigation.
Bioactive Systems	Paneled living walls (adjacent) Indirect green façades (external)	Niche/Theoretical	Synergistic CO2 capture; potential biofuel production.	The physical integration between green plants and microalgae panels.	Biological symbiosis; microalgae/plant calibration.	Biomass production monitoring; wastewater/nutrient management.
Double Skin Systems	General VGS (internal) Indirect green façades (in cavity, external) Paneled living walls (external horizontal planter boxes)	High/Emerging	Natural shading; evaporative cooling within the cavity.	Vegetation shading and transpiration, as well as the microclimate within the buffer zone cavity.	Cavity ventilation and a south-facing orientation for high annual savings.	Long-term monitoring of seasonal performance; buffer zone microclimate.
Glazing Systems	Paneled living wall (adjacent) Indirect green facades (external)	Moderate/Challenging	Practical for high WWR buildings; cooling load reduction.	Combined efficiency of plant and glass modulation.	HDR imagery analysis; visual comfort; glare mitigation.	Dynamic management of plant growth to ensure optimal natural lighting.

provides a VGS-AFT compatibility matrix that serves as a technical roadmap. This matrix translates the results of the systematic analysis into a guide for selecting the most effective hybrid façade scenario. Furthermore, it evaluates each VGS-AFT pairing using categories directly derived from the quadrants of the thematic map (Figure 8), including complementarity (niche, moderate, high) and research maturity (theoretical, indicating the “research frontier”, emerging in its early growth phase, challenging hitting a technical border, or synergistic, indicating the ability to work together more effectively). This framework measures how effectively the targeted VGS enhances the host AFT system and the current level of scientific validation of this specific synergy, aligning each hybrid scenario with the four phases of the design strategy. This roadmap ensures that greenery is treated as an active element in sustainable building envelopes, guiding architects and engineers from experimental “frontiers” to optimized, high-performance applications, as follows:

• Phase 1 (Conceptualization): A designer begins by identifying the primary performance objective (e.g., power generation versus cooling load reduction) and selects a scenario from the matrix that aligns with the climate analysis, urban context, and building configurations, considering the maturity of the research.
• Phase 2 (Hybridization): The primary integration objective of Phase 1 should be used to guide generative modeling and the simulation of how biological and mechanical layers interact in the hybrid scenario.
• Phase 3 (Optimization): Apply critical technical detail observations to address the frontier challenges identified in this study through an iterative optimization process, such as structural loads or heat transfer distances.
• Phase 4 (Development): Apply the defined development axis to move beyond static installation, using IoT and POE to manage adaptive performance over the long term.

This step-by-step application demonstrates how the proposed design strategy becomes a practical operational tool, noting that this tool represents only the many possible paths this strategy offers and does not show any implemented or experimentally proven applications; rather, it serves as a roadmap for further interdisciplinary research by architects and engineers.

5. Challenges and Limitations of the Current Study

This research was conducted on 1 January 2026, using a limited set of keywords and restricted to specific subject categories to ensure a focused dataset that aligned with the study objectives. Thus, the following are the challenges and limitations encountered in this study:

• Scope of research indicators: The study examined previous studies in terms of their impact on the environmental performance indicators of the building; however, the characteristics of irrigation systems, maintenance requirements, costs, and LCA for each integration case remain outside the scope of this study.
• Implementation of the proposed strategy: The proposed four-phase design strategy is currently a theoretical synthesis derived from fragmented research data; its practical deployment remains a “research frontier”. A primary limitation is the lack of empirical validation for the complete four-phase cycle in a singular real-world project. Therefore, the strategy should be viewed as a flexible roadmap rather than a rigid protocol, requiring further refinement through multi-year pilot studies to account for the unpredictable nature of biological growth and mechanical wear.
• Database Bias: While Scopus and Web of Science databases were utilized to minimize bias, the dominance of certain geographic hubs may prioritize specific terminologies over others, potentially masking smaller but highly specialized research nodes on hybrid façade scenarios.
• Time interval: The latest innovations and applications (from 2024 to 2026) may not be reflected in the published literature due to publication schedules. Also, some specific datasets may have access restrictions or require institutional affiliations, limiting their practical usefulness to all researchers.
• Language and keyword selection: This study focused on English-language publications, which may have overlooked relevant research published in other languages. Additionally, the absence of specific keywords related to VGSs, as well as AFTs, in the global flowchart indicates that the field still lacks standardized and universal terminology for hybrid façades scenarios. However, by using these broader terminologies, the strategy allows for the inclusion of multidimensional studies. This enables this study to offer a more comprehensive perspective that addresses studies related to energy, building technology, and environmental sciences.
• Qualitative analysis methodology: This study moved beyond automated analysis and performed a qualitative, manual “in-depth analysis” of the 415 papers. This allowed for the identification of integrating AFT system gaps that quantitative software has not yet detected. Thus, the proposed four-phase design strategy was specifically designed to bridge this gap between the general building performance and the specific technical integration.

Recognizing these limitations allows for a balanced interpretation of the results and paves the way for a conclusion. Based on this understanding, the following conclusions section highlights the main contributions and overall significance of the study.

6. Conclusions

This systematic review synthesized evidence from 415 peer-reviewed publications (2015 to early 2026) to evaluate the evolution of hybrid façades through the integration of vertical greenery systems (VGSs) and advanced façade technologies (AFTs). The findings demonstrate a significant global shift in building envelope design, transitioning from passive aesthetic barriers into active, multifunctional systems essential for urban resilience.

The bibliometric and thematic analyses indicate that, while VGSs are established nature-based solutions (NbSs) for providing sustainable building envelopes, their efficacy is maximized when integrated with technological systems. The research indicates that VGS–photovoltaic (PV) and double-skin (DS) systems currently represent the most mature integration scenarios, offering superior thermal regulation and energy efficiency through synergistic effects like transpiration cooling and thermal buffering.

However, significant research gaps remain at the “research frontier” for kinetic, modular, bioactive, and glazing systems integrations. These areas face persistent challenges regarding biological growth unpredictability, structural load management, and a lack of standardized technical workflows. Furthermore, the study identifies a critical need for long-term lifecycle assessments (LCAs) and the implementation of smart technologies, such as artificial intelligence (AI), to optimize real-time maintenance and irrigation management.

To address the identified lack of standardized procedures, this study proposed a structured four-phase design strategy: conceptualization, hybridization, optimization, and development. This roadmap provides architects and engineers with a systematic methodology for decision-making regarding harmonizing biological elements and mechanical systems, ensuring that hybrid façades function as truly integrated, high-performance components rather than merely additive elements.

In summary, the transition toward VGS-AFT hybrid façades is essential for aligning the building sector with Sustainable Development Goals (SDGs), specifically targeting clean energy (SDG 7), resilient cities (SDG 11), and climate action (SDG 13). By bridging the gap between ecological benefits and technological innovation, this research provides a viable pathway for creating biophilic, high-performance urban environments capable of meeting 21st-century energy demands. The immediate next step is to experimentally test this four-stage strategy through diverse case studies. This validation is essential for transforming hybrid facades from experimental models into established, data-driven architectural standards. The immediate next step is to empirically test this four-phase strategy through diverse case studies. Such validation is essential to transition hybrid facades from experimental models to established, data-driven architectural standards.