Search Results (221)

This paper presents a computationally efficient two-stage analytical framework for predicting daylight performance in buildings. It is designed to support real-time applications in smart lighting and intelligent building management systems. This approach combines a facade lighting model—driven by solar geometry and atmospheric transmittance—with an interior light distribution module that represents the window as a discretized light source. This formulation provides a lightweight alternative to computationally intensive ray tracing methods. It allows rapid estimation of spatial lighting patterns with minimal input data. The framework is validated using a one-year measurement campaign with class A photometric sensors in three facade orientations. The facade module achieved an average relative error below 15%, while the interior lighting model yielded an RMSE of 83 lx (≈10% error). The integrated system demonstrated an overall average deviation of 18.6% under different sky and season conditions. Owing to its low computational complexity and physically transparent formulation, the proposed method is suitable for deployment in smart building platforms, including daylight-responsive lighting control, embedded energy management systems, and digital twins requiring fast and continuous simulation of daylight availability. Full article

Daylighting is essential in residential building design because it influences energy efficiency and visual comfort while also supporting occupants’ health and overall well-being. Adequate natural light exposure aids circadian regulation and psychological restoration and enhances indoor environmental quality. This study examines how the window-to-wall ratio, skylight-to-roof ratio, and building orientation in a selected low-rise residential building can be optimized to ensure sufficient daylight in warm-humid climates. Using on-site illuminance measurements and climate-based simulations, the daylight performance is evaluated using metrics such as useful daylight illuminance, spatial daylight autonomy, and annual sunlight exposure. Results indicated that a 5% skylight-to-roof ratio (such as a 1:2 skylight setup), combined with a 22% window-to-wall ratio and glazing with a visible transmittance of 0.45, provides a balanced improvement in daylight availability for the chosen case study. The selected configuration optimizes spatial daylight autonomy and useful daylight illuminance while keeping annual sunlight exposure within recommended levels based on the surrounding building landscape. The findings emphasize the importance of tailoring daylighting strategies to site-specific orientation, glazing options, and design constraints. The approach and insights from this case study can be beneficial for incorporating into similar low-rise residential buildings in warm-humid contexts. Incorporating daylight-responsive design into urban and architectural planning supports several United Nations Sustainable Development Goals (SDG 3, 11, and 13). Full article

The construction sector’s significant energy consumption poses a substantial challenge to achieving global “Carbon Peak and Carbon Neutrality” goals. This study addresses this challenge by proposing a sustainable design framework to optimize atrium spaces in commercial complexes within severe cold regions, where the conflict between high heating energy demands and the pursuit of high-quality spatial experiences is acute. Our climate-adaptive method integrates parametric modeling (Grasshopper) with building performance simulation (Ladybug Tools and Honeybee) to form a multi-objective optimization process using the NSGA-II algorithm. The goal is to simultaneously minimize operational energy (by reducing the seasonal solar heat gain difference, D-RAD) and enhance occupant well-being (by improving useful daylight illuminance, SUMUDI, and thermal discomfort, SUMPPD). Results demonstrate that our framework generated design solutions that significantly improve environmental performance compared to a baseline model: aggregate useful daylight illuminance (SUMUDI) increased by 90.2%, the solar heat gain difference (D-RAD) was reduced by 40.8%, and thermal discomfort (SUMPPD) decreased by 22.7%. This research provides a quantifiable and replicable methodology for sustainable architectural design, contributing directly to the measurement and monitoring of sustainability in the built environment by balancing energy conservation with human-centric design. Full article

This systematic review examined the use of building-integrated photovoltaics (BIPVs) in high-rise buildings, focusing on early-stage design strategies to enhance energy performance. With limited rooftop space in tall buildings, façades offer a promising alternative for solar energy generation. Using the PRISMA framework, 41 articles were synthesized to identify key parameters influencing the effectiveness of BIPV systems. This included environmental and urban contexts, building form and orientation, façade configuration, and typology-specific characteristics for residential, office, and mixed-use buildings. The findings highlight the importance of integrating BIPV from the earliest stages of the design process. Local climate and latitude guide optimal façade orientation and form, while module efficiency can be improved with ventilation, air gaps, and appropriate spacing. Urban density, site placement, and shading patterns also significantly affect overall energy output. Podiums and multifaceted building forms enhance solar exposure and reduce self-shading, while building height, orientation, and spacing further influence BIPV potential. Different building types require tailored strategies to balance energy generation, daylight, and architectural quality. Finally, the review identified research gaps and proposed future directions to support architects, designers, and urban planners in effectively incorporating photovoltaic systems into high-rise building design. Full article

The widespread use of transparent building envelope structures satisfies people’s needs for architectural esthetics and daylighting. However, they also feature notable drawbacks such as high energy consumption, poor thermal insulation performance of traditional glass curtain walls, significant solar heat gain in summer and heat loss in winter, which lead to “cold in winter and hot in summer” indoors, reliance on high-power air conditioning, and energy consumption far exceeding that of opaque walls. Even when coated or insulated glazing is adopted, improper design can still fail to effectively reduce the overall heat transfer coefficient, placing higher demands on the daylighting performance and solar radiation control of transparent envelopes in existing buildings. Through experiments and numerical simulations, this study systematically analyzes the performance of different types of glass used in transparent building envelope structures and their impacts on building energy consumption. Based on the climatic characteristics of central-southern Anhui, measured data were compared between a Low E-glass sunroom and a conventional tempered glass sunroom. The results show that the solar radiation transmittance of the Low-e glass is only 45.31% of that of ordinary glass, the peak indoor temperature is reduced by 6–7 °C, and nighttime temperature fluctuations are smaller, verifying its excellent thermal insulation performance and thermal stability. To further investigate, the Ecotect software 2011 was used to simulate the daylighting performance of 12 types of glazing and the radiation transmittance under 19 conditions. The results indicate: triple-glazed vacuum composite silver-coated glass exhibits excellent shading performance suitable for summer; single-silver-coated glass has the best daylighting performance, and Triple-Silver coatings combined with high-transmission substrates can improve the daylight factor by 10.55%; argon-filled insulated glazing reduces radiation by 6.5% compared with ordinary IGUs, making it more suitable for the climate of central-southern Anhui. The study shows that optimization of transparent envelopes must be predicated on regional climate, combining experimentally validated glazing thermal parameters with simulation-based design optimization to provide theoretical support and technical references for glass selection and transparent envelope design in near-zero energy buildings in central-southern Anhui. Full article

This article presents the accumulated technical and scientific knowledge from energy performance upgrade work in emblematic and essential municipal and public buildings in Crete and the Greek islands, such as the Venetian historical building Loggia, which is used as the Heraklion City Hall, the Natural History Museum of Crete, Pancretan Stadium, the municipal swimming pool of the municipality of Minoa Pediadas, the indoor sports hall in Leros, primary schools, high schools and a cultural center. Each one of the aforementioned buildings has a distinct use, thus covering almost all different categories of municipal or public buildings and facilities. The applied energy performance upgrade process in general terms is: (1) Mapping of the current situation, regarding the existing infrastructure and final energy consumption. (2) Formulation and sizing of the proposed passive measures and calculation of the new indoor heating and cooling loads. (3) Selection, sizing and siting of the proposed active measures and calculation of the new expecting energy sources consumption. (4) Sizing and siting of power and heat production systems from renewable energy sources (RES). Through the work accomplished and presented in this article, practically all the most technically and economically feasible passive and active measures were studied: insulation of opaque surfaces, opening overhangs, natural ventilation, replacement of openings, daylighting solar tubes, open-loop geo-exchange plants, refrigerant or water distribution networks, air-to-water heat pumps, solar thermal collectors, lighting systems, automation systems, photovoltaics etc. The main results of the research showed energy savings through passive and active systems that can exceed 70%, depending mainly on the existing energy performance of the facility. By introducing photovoltaic plants operating under the net-metering mode, energy performance upgrades up to zero-energy facilities can be achieved. The payback periods range from 12 to 45 years. The setup budgets of the presented projects range from a few hundred thousand euros to 7 million euros. Full article

Kinetic façades represent a climate-responsive design solution that improves building adaptability by responding to seasonal needs such as daylighting and shading. They offer an attractive retrofit strategy that improves both the esthetics and environmental performance of buildings. This study investigated the integration of an origami-inspired kinetic façade into a student dormitory building located in Dhahran, Saudi Arabia. Using numerical simulations, 35 façade configurations were analyzed under varying conditions of façade orientations, closure ratios (from 5% to 95%), and cavity depths (from 20 cm to 100 cm). The findings highlight the critical impact of kinetic façade design characteristics on daylight availability and solar exposure and the required trade-off between these two variables. In this context, this study observed that at higher façade closure ratios, increasing cavity depth could effectively mitigate daylight reduction by promoting reflected daylight penetration inside the cavity. As for heat gains and cooling load reduction, mid-range façade closure, 50 cm in this study, achieved balanced performance across the three examined orientations. However, the southern façade showed slightly higher efficiency compared to the eastern and western façades, which achieved lower cooling reductions and showed a similar UDI compromise. Thus, a dynamic façade operation is recommended, where higher closure ratios could be applied during peak solar hours on the east in the morning and the west in the afternoon to maximize cooling savings, while moderate closure ratios can be maintained on the south to preserve daylight. Future work should incorporate real-time climatic data and smart control technologies to further optimize kinetic façade performance. Full article

This study presents the Level(s)+37 Framework, a decision-support tool consisting of 37 indicators designed to evaluate and enhance passive design performance, social equity, and climate resilience in primary and secondary schools. Aligned with the six macro-objectives of the European Level(s) scheme, the indicators are organised into seven thematic clusters—thermal comfort, indoor air quality, solar control and daylighting, environmental ergonomics, ecological sustainability and circular economy, climate justice and social equity, and educational value with stakeholder participation—covering all life-cycle stages from design to retrofit. The framework was developed through a six-phase mixed-methods protocol, including a systematic review of 210 scientific and regulatory sources, 24 semi-structured interviews with school stakeholders, and a Delphi–AHP involving 170 experts. The resulting hierarchy of indicators (CI < 0.10; Kendall’s W = 0.78) ensures methodological robustness and contextual relevance for the Spanish school building stock. By integrating environmental, technical, and pedagogical dimensions, the Level(s)+37 Framework serves as both an evaluation tool and a catalyst for sustainable transformation, promoting participatory governance and climate-responsive learning environments. Full article

Biophilic design has traditionally evolved from temperate-zone contexts, where access to nature is more readily available, and has rarely addressed the challenges of extreme climatic conditions. The potential of biophilic design to enhance health and well-being in cold environments, where exposure to nature must adapt to low temperatures, limited solar radiation, and pronounced photoperiod variation, remains underexplored. This study conducts a systematic meta-synthesis of biophilic architectural design strategies in Arctic and Sub-Arctic regions, adopting the SALSA (Search, Appraisal, Synthesis, and Analysis) framework in alignment with PRISMA guidelines to ensure methodological transparency and reproducibility. Nine peer-reviewed studies published between 2019 and 2024 were analyzed using qualitative coding and synthesis in NVivo. The findings identify thermal comfort, daylight, and circadian regulation as the most influential biophilic parameters, while greenery and water features, common in temperate frameworks, were limited due to environmental constraints. Key interventions include adaptive envelopes, optimized window design, intermediate buffer zones, and materials that balance insulation with sensory enrichment. The study proposes an “Interventions–Parameters–Outcomes” framework that illustrates the interrelationships among biophilic strategies, health-related outcomes, and climatic adaptation. While all studies originated from northern Canada, the conceptual framework provides a transferable foundation for future empirical validation and comparative research across diverse cold-climate regions, contributing to the advancement of climate-responsive, human-centered design in extreme environments. Full article

Within the framework of the Healthy China strategy, daylighting in primary and secondary schools is crucial for students’ health and learning efficiency. Most schools in China still face insufficient and uneven daylighting, along with limited outdoor solar exposure, underscoring the need for systematic optimization. Guided by the “Daylighting School” concept, this study proposes a campus design model that integrates indoor daylighting with outdoor activity opportunities and explores a generative optimization approach. The research reviews daylighting and thermal performance metrics, summarizes European and American “Daylighting School” experiences, and develops three classroom prototypes—Standard Side-Lit, High Side-Lit, and Skylight-Lit—together with corresponding campus layout models. A two-stage optimization experiment was conducted on a high school site in Guangzhou. Stage 1 optimized block location and functional layout using solar radiation illuminance and activity accessibility distance. Stage 2 refined classroom configurations based on four key performance indicators: sDA, sGA, UOD, and APMV-mean. Results show that optimized layouts improved activity path efficiency and daylight availability. High Side-Lit and Skylight-Lit classrooms outperformed traditional Side-Lit in illuminance, uniformity, and glare control. To improve efficiency, an ANN-based prediction model was introduced to replace conventional simulation engines, enabling rapid large-scale assessment of complex classroom clusters and providing architects with real-time decision support for daylight-oriented educational building design. Full article

This study numerically investigates and designs, through electromagnetic and ray-tracing simulations, two types of double-sided metasurface thermal insulation glazing to maintain visible light (VIS) transmittance while effectively suppressing near-infrared (NIR) transmission, with a partial reduction in deep-blue (DB) transmission, thus reducing air-conditioning load and lighting energy consumption and contributing to overall building energy efficiency. Both designs were optimized and analyzed entirely through simulations, using structural parameter sweeps and AM 1.5 solar spectrum weighting. Design I is composed of two all-dielectric metasurfaces, aiming to maximize VIS transmittance while partially suppressing DB and reducing NIR transmission. Design II integrates a metallic layer with dielectric structures on the front side and employs an all-dielectric metasurface on the back side to enhance NIR blocking and maintain low transmittance under oblique incidence. Simulation results show that Design II outperforms Design I in NIR suppression, exhibiting lower and more stable transmittance across incident angles, while Design I achieves higher VIS transmittance. These findings present a promising pathway for developing high-performance, lightweight glazing for sustainable buildings, improving energy efficiency by balancing solar heat control and daylight utilization. Full article

In South Korea, sunlight rights and daylight rights are legally distinguished, yet no standardized methodology exists for their quantitative assessment. Current evaluations of sunlight rights are narrowly defined, relying on the duration of direct solar penetration at the window center during the winter solstice, while excluding reflected and diffuse light. This restrictive approach has led to confusion among both researchers and legal practitioners, as it diverges from daylighting evaluations that account for indoor brightness and energy performance. The recent enactment of regulations to secure solar access in schools has further intensified disputes between educational institutions striving to protect students’ visual comfort and developers seeking to maximize building potential. To address this gap, this study proposes an evaluation framework tailored to the Korean context. A reference classroom model representative of standard Korean schools was developed, and simulations were conducted by introducing obstructing building masses to block direct sunlight. The methodology evaluated key variables, including time of day and solar altitude, and analyzed daylighting performance and lighting-related energy consumption under obstructed conditions. The results show that blocking sunlight through south-facing windows reduces daylighting performance by 89% to 98%, leading to additional reliance on artificial lighting, with energy use increasing between 128 Wh and 768 Wh. These findings underscore the limitations of current legal interpretations based solely on sunlight duration and highlight the necessity of adopting performance-based evaluation methods. Protecting school sunlight rights through such approaches is essential to enhancing classroom visual environments and reducing energy demand. Full article

Achieving optimal daylighting in buildings necessitates complex and expensive control systems. This research addresses this challenge by proposing a simple and more practical solution: a parametric louver system based on rotating slats controlled by stepper motors, powered by an Integrated Circuit platform (Arduino board), which can translate the digital figures (the rotation angles) to a physical action. The system automatically adjusts the slats in accordance with solar altitudes and reflects them to specific targets over the ceiling. This ensures a uniform and comfortable distribution of daylight throughout a room. This system was developed using Grasshopper as the parametric software, with future control planned via a user-friendly mobile app through a preliminary prototype. This daylighting system prioritises human visual comfort while targeting a significant 53% reduction in electrical lighting energy consumption. The system aims to enhance occupant well-being to significantly increase energy savings, making it a compelling solution for sustainable building design. Full article

This research investigates the integration of green cores as central biophilic elements in residential architecture, proposing a climate-responsive design methodology grounded in architectural optimization. The study begins with the full-scale refurbishment of a compact urban apartment, wherein interior partitions, fenestration and material systems were reconfigured to embed vegetated zones within the architectural core. Light exposure, ventilation potential and spatial coherence were maximized through data-driven design strategies and structural modifications. Integrated planting modules equipped with PAR-specific LED systems ensure sustained vegetation growth, while embedded environmental infrastructure supports automated irrigation and continuous microclimate monitoring. This plant-centered spatial model is evaluated using quantifiable performance metrics, establishing a replicable framework for optimized indoor ecosystems. Photosynthetically active radiation (PAR)-specific LED systems and embedded environmental infrastructure were incorporated to maintain vegetation viability and enable microclimate regulation. A programmable irrigation system linked to environmental sensors allows automated resource management, ensuring efficient plant sustenance. The configuration is assessed using measurable indicators such as daylight factor, solar exposure, passive thermal behavior and similar elements. Additionally, a post-occupancy expert assessment was conducted with several architects evaluating different aspects confirming the architectural and spatial improvements achieved through the refurbishment. This study not only demonstrates a viable architectural prototype but also opens future avenues for the development of metabolically active buildings, integration with decentralized energy and water systems, and the computational optimization of living infrastructure across varying climatic zones. Full article

This study presents a comprehensive assessment of lighting conditions in the Intensive Care Units (ICUs) of two major hospitals in the Democratic Republic of Congo (DRC): Hospital du Cinquantenaire in Kinshasa and Jason Sendwe Hospital in Lubumbashi. A mixed-methods approach was employed, integrating continuous illuminance monitoring with structured staff surveys to evaluate visual comfort in accordance with the EN 12464-1 standard for indoor workplaces. Objective measurements revealed that more than 52.2% of the evaluated ICU workspaces failed to meet the recommended minimum illuminance level of 300 lux. Subjective responses from healthcare professionals indicated that poor lighting significantly reduced job satisfaction by 40%, lowered self-rated task performance by 30%, decreased visual comfort scores from 4.1 to 2.6 (on a 1–5 scale), and increased the prevalence of well-being symptoms (eye fatigue, headaches) by 25–35%. Frequent complaints included eye strain, glare, and discomfort with posture, with these issues often exacerbated during the rainy season due to reduced natural daylight. The study highlights critical deficiencies in current lighting infrastructure and emphasizes the need for urgent improvements in clinical environments. Moreover, inconsistent energy supply to these healthcare settings also impacts the assurance of visual comfort. To address these shortcomings, the study recommends transitioning to energy-efficient LED lighting, enhancing access to natural light, incorporating circadian rhythm-based lighting systems, enabling individual lighting control at workstations, and ensuring a consistent power supply via the integration of solar inverters to the grid supply. These interventions are essential not only for improving healthcare staff performance and safety but also for supporting better patient outcomes. The findings offer actionable insights for hospital administrators and policymakers in the DRC and similar low-resource settings seeking to enhance environmental quality in critical care facilities. Full article