Search Results (45)

The growing number of daylighting metrics—often overlapping in scope or terminology—combined with the need for prior familiarization to interpret and apply them effectively, has created a barrier to their adoption beyond academic settings. Consequently, this study analyzes a representative set of established and emerging daylighting metrics to evaluate applicability, synergies, and limitations. Particular attention is given to their implications for occupant health, well-being, performance, and energy use, especially within the context of sensorless smart control systems. A virtual room model was simulated using DaySim 3.1 in two contrasting climates—Seville and London—with varying window-to-wall ratios, orientations, and occupancy schedules. The results show that no single metric provides a comprehensive daylighting assessment, highlighting the need for combined approaches. Daylighting Autonomy (DA) proved useful for task illumination, while Useful Daylight Illuminance (UDI) helped identify areas prone to excessive solar exposure. Spatial metrics such as Spatial Daylight Autonomy (sDA) and Annual Sunlight Exposure (ASE) offer an overview but lack necessary granularity. Circadian Stimulus Autonomy (CSA) appears promising for evaluating circadian entrainment, though its underlying models remain under refinement. Continuous Overcast Daylight Autonomy (DAo.con) shows the potential for sensorless lighting control when adjusted for orientation. A nuanced, multi-metric approach is therefore recommended. Full article

With the rapid advancement of urbanization in China, the demand for community-based elderly care facilities (CECFs) has been increasing. One pressing challenge is the question of how to provide CECFs that not only meet the health needs of the elderly but also make efficient use of limited urban land resources. This study addresses this issue by adopting an integrated multi-method research framework that combines multi-objective optimization (MOO) algorithms, Spearman rank correlation analysis, ensemble learning methods (Random Forest combined with SHapley Additive exPlanations (SHAP), where SHAP enhances the interpretability of ensemble models), and Self-Organizing Map (SOM) neural networks. This framework is employed to identify optimal building configurations and to examine how different architectural parameters influence key daylight performance indicators—Useful Daylight Illuminance (UDI) and Daylight Factor (DF). Results indicate that when UDI and DF meet the comfort thresholds for elderly users, the minimum building area can be controlled to as little as 351 m² and can achieve a balance between natural lighting and spatial efficiency. This ensures sufficient indoor daylight while mitigating excessive glare that could impair elderly vision. Significant correlations are observed between spatial form and daylight performance, with factors such as window-to-wall ratio (WWR) and wall thickness (WT) playing crucial roles. Specifically, wall thickness affects indoor daylight distribution by altering window depth and shading. Moreover, the ensemble learning models combined with SHAP analysis uncover nonlinear relationships between various architectural parameters and daylight performance. In addition, a decision support method based on SOM is proposed to replace the subjective decision-making process commonly found in traditional optimization frameworks. This method enables the visualization of a large Pareto solution set in a two-dimensional space, facilitating more informed and rational design decisions. Finally, the findings are translated into a set of practical design strategies for application in real-world projects. Full article

Lecture halls are characterized by large spatial dimensions, deep floor plans, and high occupant densities. Lectures are typically conducted using multimedia and blackboard-based teaching, placing higher demands on the indoor light and thermal environment compared to standard classrooms. This study aims to simulate the interrelationships between multiple building envelope parameters and building performance, in order to improve visual and thermal comfort while reducing energy consumption in cold-region lecture halls. Based on seven key envelope parameters—including openable window area ratio, west-facing window-to-wall ratio, exterior insulation thickness, shading element spacing, angle and width, and window glass type—a multi-objective optimization framework was established. The optimization process targeted three key performance indicators—useful daylight illuminance (UDI), energy use intensity (EUI), and thermal comfort percentage (TCP)—in the context of a stepped classroom. The results show that increasing the thickness of exterior insulation and reducing the width of shading components contribute positively to photothermal comfort without compromising thermal and visual performance. Compared with the baseline design, optimized schemes that incorporate appropriate west-facing window-to-wall ratios, openable window areas, insulation thicknesses, and external shading designs can reduce annual energy consumption by up to 10.82%, and increase UDI and TCP by 12.79% and 36.41%, respectively. These improvements are also found to be economically viable. Full article

Numerous studies have demonstrated that appropriate use of daylight in educational spaces significantly enhances students’ health and academic performance. However, classrooms in Tehran still suffer from considerable daylighting challenges. In many cases, desks near windows are exposed to excessive brightness, while areas farther from the windows lack adequate illumination. This often leads to the use of curtains and artificial lighting, resulting in higher energy consumption and potential negative impacts on student learning. Light shelf systems have been proposed as effective daylighting solutions to improve light penetration and distribution. According to previous research, three key parameters—geometry, depth, and surface reflectance—play a critical role in the performance of light shelves. However, prior studies have typically focused on improving one or two of these parameters in isolation. There is a lack of research evaluating all three parameters simultaneously to determine season-specific configurations for optimal performance. Addressing this gap, the present study investigates the combined effects of light shelf geometry, depth, and reflectance across different seasons and proposes a system that dynamically adapts these parameters throughout the year. In winter, the system also integrates photovoltaic panels to reduce glare and generate electricity for its operation. Simulation results indicate that the proposed system leads to a 21% improvement in Useful Daylight Illuminance (UDI), a 65% increase in thermal comfort, and a 10% annual reduction in energy consumption. These findings highlight the potential of the proposed system as a practical and energy-efficient daylighting strategy for educational buildings in sunny regions such as Tehran. Full article

Centralized daylight control has been extensively studied for its ability to optimize useful daylight while mitigating glare in targeted areas. However, this approach lacks a comprehensive visual comfort framework, as it does not simultaneously address spatial glare distribution, uniform high useful daylight levels across all sensor points, and overheating prevention through regulated annual solar exposure. Nevertheless, decentralized control facilitates autonomous operation of the individual façade components, addressing all the objectives. This study integrates a biomimetic functional approach with building performance simulations by computational design to evaluate different kinetic façade configurations. Through the implementation of parametric modeling and daylight analysis, we have identified an optimal angular configuration (60° for the focal region, 50° for the non-focal region) that significantly increases building performance. The optimized design demonstrates substantial improvements, reducing excessive sunlight exposure by 45–55% and glare incidence by 65–72% compared to other dynamic solutions. The recommended steeper angles achieve superior performance, maintaining high useful daylight illuminance (UDI > 91.5%) while dramatically improving visual comfort. Sensitivity analysis indicates that even minor angular adjustments (5–10°) can induce a 10–15% variation in glare performance, emphasizing the necessity of precise control mechanisms in both focal and non-focal regions of the façade. These findings establish a framework for creating responsive building façades that balance daylight provision with occupant comfort in real-time operation. Full article

In southern Hunan province, a vital element of China’s architectural cultural legacy, the quality of the indoor lighting environment influences physical performance and the transmission of spatial culture. The province encounters minor environmental disparities and diminishing liveability attributed to evolving construction practices and cultural standards. The three varieties of traditional residences in Shanggantang Village are employed to assess the daylight factor (DF), illumination uniformity (U0), daylight autonomy (DA), and useful daylight illumination (UDI). We subsequently integrate field measurements with static and dynamic numerical simulations to create a multi-dimensional analytical framework termed “measured-static-dynamic”. This method enables the examination of the influence of floor plan layout on light, as well as the relationship between window size, building configuration, and natural illumination. The lighting factor (DF) of the core area of the central patio-type residence reaches 27.7% and the illumination uniformity (U0) is 0.62, but the DF of the transition area plummets to 1.6%; the composite patio type enhances the DF of the transition area to 1.2% through the alleyway-assisted lighting, which is a 24-fold improvement over the offset patio type. Parameter optimization showed that the percentage of all-natural daylighting time (DA) in the edge zone of the central patio type increased from 21.4% to 58.3% when the window height was adjusted to 90%. The results of the study provide a quantitative basis for the optimization of the light environment and low-carbon renewal of traditional residential buildings. Full article

Given their dominant role in energy expenditure within China’s Hot Summer and Warm Winter (HSWW) zone, high-fidelity performance prediction and multi-objective optimization framework during the early design phase are critical for achieving sustainable energy efficiency. This study presents an innovative approach integrating machine learning (ML) algorithms and multi-objective genetic optimization to predict and optimize the performance of high-rise office buildings in China’s HSWW zone. By integrating Rhino/Grasshopper parametric modeling, Ladybug Tools performance simulation, and Python programming, this study developed a parametric high-rise office building model and validated five advanced and mature machine learning algorithms for predicting energy use intensity (EUI) and useful daylight illuminance (UDI) based on architectural form parameters under HSWW climatic conditions. The results demonstrate that the CatBoost algorithm outperforms other models with an R² of 0.94 and CVRMSE of 1.57%. The Pareto optimal solutions identify substantial shading dimensions, southeast orientations, high aspect ratios, appropriate spatial depths, and reduced window areas as critical determinants for optimizing EUI and UDI in high-rise office buildings of the HSWW zone. This research fills a gap in the existing literature by systematically investigating the application of ML algorithms to predict the complex relationships between architectural form parameters and performance metrics in high-rise building design. The proposed data-driven optimization framework provides architects and engineers with a scientific decision-making tool for early-stage design, offering methodological guidance for sustainable building design in similar climatic regions. Full article

According to the China Building Energy Consumption and Carbon Emissions Research Report (2023), the construction industry accounts for 36.3% of total societal energy consumption, with residential buildings contributing significantly due to their extensive coverage and high operational frequency. Addressing energy efficiency and carbon reduction in this sector is critical for achieving national sustainability goals. This study proposes an optimization methodology for rural dwellings in Inner Mongolia, focusing on reducing energy demand while enhancing indoor thermal comfort and daylight performance. A parametric model was developed using Grasshopper, with energy consumption, thermal comfort (PPD), and Useful Daylight Illuminance (UDI) simulated through Ladybug and Honeybee tools. Key parameters analyzed include building morphology, envelope structures, and indoor thermal environments, followed by systematic optimization of building components. To refine multi-objective inputs, a specialized wall database was established, enabling categorization and dynamic visualization of material properties and construction methods. Comparative analysis demonstrated a 22.56% reduction in energy consumption, 19.26% decrease in occupant thermal dissatisfaction (PPD), and 25.44% improvement in UDI values post-optimization. The proposed framework provides a scientifically validated approach for improving energy efficiency and environmental adaptability in cold-climate rural architecture. Full article

Direct sunlight causes glare and reduces indoor daylight quality, making shading systems essential. This study proposes and validates a perforated shading screen (PSS) to enhance daylighting and energy efficiency. A hybrid approach integrating parametric modeling, machine learning, multi-criteria decision-making (MCDM), and genetic algorithm (GA) is used to optimize the design incorporating architects’ preferences. The Analytic Network Process (ANP) is used to assign weights to performance metrics while accounting for interdependencies. The study evaluates PSS performance in three hot climate regions—Cairo, Riyadh, and Kuching—on both south and west elevations, comparing it to traditional fins. Results show that PSS consistently outperforms fins, significantly improving daylight and energy performance. The Useful Daylight Illuminance (UDI) increased by up to 105.32%, Continuous Daylight Autonomy (CDA) by up to 11.87%, while Annual Solar Exposure (ASE), Solar Gain (SG), and Energy Use Intensity (EUI) were reduced by up to 100%, 88.07%, and 45.2%, respectively. To validate the findings, the optimal PSS design from a selected case study was 3D-printed and experimentally tested. Results confirmed enhanced daylight distribution and reduced glare, improving occupant comfort. The proposed PSS offers an effective shading solution adaptable to various climates, balancing daylighting needs and energy efficiency. Full article

Open atrium spaces in university libraries have emerged as a prevalent architectural trend. While increasing daylighting through enlarged glazing areas enhances the indoor environment, it simultaneously introduces significant thermal challenges in cold regions where environmental comfort demands lead to higher energy loads. This study investigates the optimization of daylighting–thermal performance balance through a multi-objective parametric approach to address the inherent conflicts between environmental quality and energy efficiency in atrium design. In this paper, we take the library project in the cold region as a practical case, use the measured data to support the simulation experiment, combine the parametric platform and multi-objective coupling optimization algorithm to carry out digital modeling, and explore the dynamic relationship between the atrium light, heat environment, and the value of energy consumption under the influence of a variety of parameters. The experimental results show that the quality and energy efficiency of the atrium light environment are improved after parameter optimization. The energy consumption per unit area (EUI) is reduced by 84.84 kwh/m²–106.83 kwh/m² while the adequate natural illuminance (UDI) is increased by 5.06–27.64%, which confirms the feasibility of the research and development of the building light–heat coupling optimization technology route and program module. This paper aims to explore the quantitative law of design elements on light–heat balance at the early stage of architectural design and to provide a theoretical basis and reference blueprint for improving the comprehensive decision-making ability of architects in sustainable design and realizing integrated and efficient program decision-making. Full article

This study examines the quality and availability of daylight in childcare facilities, focusing on compliance with Polish Technical Conditions (TCs) and comparing them with international certification systems such as BREEAM, LEED, and WELL. Polish regulations regarding sunlight exposure require revisions to support the sustainable development of buildings, impacting children’s well-being, their health, and the building’s energy efficiency. Daylight’s significance for children’s health and development underpins the investigation, highlighting its impact on the circadian rhythm, cognitive abilities, and well-being. The research utilized computational simulations with Rhinoceros 7 and Ladybug and Honeybee plugins to model a preschool room’s daylight performance under various window configurations and orientations. Quantitative and qualitative analyses were conducted, focusing on parameters such as Daylight Factor (DF), Daylight Autonomy (DA), and Useful Daylight Illuminance (UDI). The findings revealed that while the TCs’ requirements ensure minimum daylight access, they result in nonoptimal lighting quality as defined by international standards. Almost half of the surveyed rooms in the case with a WFR of one-eighth did not meet the condition for having acceptable daylight levels, as defined in the study. In the same study, only about one-third of the analyzed variants achieved the threshold for good daylight quality. At a WFR of one-eighth, no room variant reached the level considered to indicate excellent daylight quality. The results show the need for revised regulations incorporating comprehensive metrics like Climate-Based Daylight Modeling (CBDM). This study suggests that integrating advanced methods of assessing daylight quality could significantly improve daylight conditions in childcare environments. This research is a starting point for discussing the need to modernize the Polish Technical Conditions (TC) to support the sustainable development of childcare facilities in Poland. Full article

An innovative center-mounted louver ventilation window suitable for seasonal ventilation strategies was proposed, combining the regional climate of Qingdao. The sustainable development concept is embodied, which can not only reduce building energy consumption but also consider the quality of daylighting. This research constructed a comprehensive evaluation framework, taking an office building in Qingdao as an example. The framework utilized the parametric design platform Grasshopper and its environmental design plug-in Ladybugtools. It considered the daylighting performance and energy consumption of the building. This study included six different ventilation strategies, with energy use intensity and useful daylight illuminance as evaluation indicators. The results indicated that the seasonal ventilation strategies and parameters of blinds were optimized to significantly improve the energy efficiency of the building without compromising daylighting quality. The optimized solution reduces energy consumption from 83.81 kWh/m² to 55.0 kWh/m², achieving a 34.4% reduction while maintaining a high UDI. This energy-saving effect reveals the influence of different ventilation strategies on energy and daylighting. And it provides an important reference for sustainable design in similar climate contexts. Full article

Building optimisation techniques provide a rigorous framework for exploring new optimal design solutions. In this study, a genetic algorithm (GA) was used to investigate the energy efficiency of a vernacular architectural element (Rawshan) in Saudi Arabia. Two objectives were optimised using a GA simulation enhanced: energy consumption optimisation and useful daylight illuminance (UDI) optimisation. A calibrated simulation model of a typical house in Saudi Arabia was used in the study. Several metrics, such as light interference from shadows or other windows, were considered to indicate the importance of the Rawshan. Computational studies were performed using different climatic conditions, and the results were compared with and without a Rawshan element using the weather data of Mecca, Jeddah, Riyadh, and Al-Baha. In this study, the blind thicknesses on the front and sides of the Rawshan were used as optimisation variables. The results showed that using a GA with energy consumption as an objective can reduce energy consumption. One of the methods proposed in the paper can reduce energy consumption by 3.6%, 3.6%, and 16.6% for Mecca, Riyadh, and Al-Baha, respectively. The single-objective optimisation method demonstrated that Rawshan provided sufficient UDI in four cities: Mecca, Jeddah, Riyadh, and Al-Baha. The research provided optimised values for Rawshan blind thicknesses on the front and lateral sides under different optimisation constraints. The results showed that using Rawshans in modern building architecture can reduce energy consumption and improve useful daylight illuminance. Full article

University classrooms have an urgent need for energy saving and environmental optimization due to the energy consumption characteristics and the demand for a daylight environment. Classrooms in hot summer and cold winter (HSCW) areas in China are typically designed with a south-facing layout, but the indoor environment of the classrooms in actual use is not as satisfactory as it should be. This research examines the impacts of side-lit window design parameters and shading forms on the energy and daylight performance by using measurements and simulation. It is found that there is significant seasonal variation in the energy consumption of teaching buildings in HSCW areas, with cooling energy consumption being the primary focus of energy conservation. Additionally, appropriate shading measures can not only compensate for the energy deficiencies of the orientation and window-to-wall ratio (WWR), but also considerably enhance the indoor daylight conditions. The results indicate that the most effective way to optimize energy and daylight performance in classrooms is to adopt a north-facing layout with 400 mm shading louvers. The illuminance level of the working plane can be made more uniform and the useful daylight illuminance (UDI) can be increased to over 60%. Therefore, classroom designs in HSCW areas can be more flexible in terms of optimizing energy efficiency and daylight conditions by integrating various design parameters and shading measures. Full article

European non-residential buildings constructed before building energy codes consume more energy and resources than new buildings. Existing educational buildings comprise 17% of this outdated stock. These buildings can be retrofitted to create a conducive learning environment that can improve students’ comfort. The refurbishment of facades is a common solution to improve the energy performance of schools when the aim is to improve the daylighting comfort. This study develops a methodology to optimize facade renovation solutions including (1) preparation, (2) simulations of the simplified model using local shading, and (3) modeling a realistic optimized facade design. This study evaluates visual comfort by considering multiple-dimensional metrics such as useful daylight illuminance (UDI), annual sunlight exposure (ASE), illuminance uniformity, and the daylighting factor. The three parameters of the louvres on which this study focuses are the distance from the new facade to the exterior wall, the blade degrees, and slat spacing. The methodology was first applied to improve the facade proposal with reused roof tiles from the project Waste-based Intelligent Solar-control-devices for Envelope Refurbishment (WiSeR). The results illustrate that implementing these solutions efficiently improves the indoor visual comfort in the classroom while avoiding overheating issues. For a constant-gaps surface, a shading distribution with alternated gaps gives better results for the aforementioned light metrics. Specifically, the most suitable values are a 7 cm distance from the new shading system to the existing wall, slat degrees at 0, and louvre spacing at 21 cm. Full article