International Journal of

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It is accepted that the visual comfort in schools depends on the quality of the whole visual environment. This leads to the concern upon the quality and quantity of lighting. Currently in Iran, in order to calculate energy transfer for public buildings a coefficient is usually used. This coefficient considers the rate of sunlight energy absorption in these kinds of buildings. To increase the degree of accuracy in the calculation mentioned above, the authors suggest a simulation programme that can do the job precisely and accordingly. It seems that, in order to calculate the energy requirements of school buildings in Iran for heating, cooling and lighting, it is better to use a simulation programme, too. In fact, this paper considers details of lighting as part of a comprehensive programme and Iran schools design requirements for lighting. As we will see, this research describes the method of calculation of daylighting, which is used in the part of lighting simulation programme. Effective daylighting design requires consideration of different factors such as daylight factor, luminous efficacy of solar radiation, orientation factor, glass transmittance factor, average reflectance of material and etc. which are need for calculation of exterior and interior luminance. They are discussed in details in this paper.

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Day lighting is one of the important qualitative factors in housing, which is also effective on health and well-being of occupants. Extensive glass surfaces and Transparency in building facades provides good daylight quantity for interior spaces. However, this lighting system is not appropriate for climates faced with higher sunlight radiation (Such as hot-humid areas), due to overheating and disturbing the thermal comfort. There are efficient day lighting strategies in the traditional Iranian architecture as one of the valuable remaining heritages of Human experiences, which are useful for contemporary architecture. This article intends to investigate daylight quality in the houses of Bushehr from Qajar period by modeling and simulating in daylight calculation software (Dialux) and identify day lighting strategies utilized in these houses. As Bushehr city is located in the hot-humid region of Iran, is faced with high sunlight radiation, making balance between receiving light and heat gain through windows needs careful attention. The houses of Qajar period in Bushehr are evolved samples of traditional architecture in the city and Rashidy house (built in 1893) is one of them which its form and details can reveal many lessons on coping with climate by merely using renewable energies.

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Daylight in classrooms is a critical factor in school design, in terms of its impact on students’ health, learning and visual performance. Providing adequate amount of evenly distributed daylight and glare prevention are important challenges in classroom design. Window configuration significantly affects the intensity and uniformity of daylight. This paper aims to investigate the effect of window configuration on daylight performance through parametric analysis. Different window configurations such as window to wall ratio, incorporating light shelves and roof monitors have been analyzed on a typical south-east facing classroom in Kashan based on results from DesignBuilder Radiance simulation which has first been validated against field measurements. Daylighting credits of green building rating tools; Leed EQ 8.1 and BREEAM HEA1 have been used as indices for evaluating and comparing different window configurations. Results show that by increasing the window-wall-ratio to 35, 40 and 50% and by installing a roof monitor, the daylight credits of the BREEAM and LEED could be achieved respectively. According to the fact that none of these window configurations have reached the standards required by both rating tools, the authors believe that a combination of installing monitor roof and light shelves and increasing window-wall-ratio may result in enhanced daylight levels.

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Orientation of classrooms is an important challenge in architectural design of a school. However, there is a lack of appropriate knowledge about influence of orientation on students’ perception of daylighting in classrooms. This paper presents a questionnaire survey that was conducted to compare students’ perception and satisfaction with daylighting in classrooms of a high school in Tabriz, Iran. Statistical analysis of responses was done to identify daylight factor and their relationships with satisfaction with daylighting in northern and southern classrooms. In southern classrooms, satisfaction with daylighting had significantly negative and positive correlation with perception of reflected and direct glare, respectively. In northern classrooms, perception of unified daylight and control of sunlight overheating by operable windows had significantly strong and positive correlation with satisfaction with daylighting, respectively. The students’ seating location had significant influence on satisfaction with daylighting and perception of direct glare in southern classrooms. In northern classrooms, students’ seating location caused different perception of reflected glare. The results showed that orientation did not lead to significant difference between satisfactions with daylighting in northern and southern classrooms. Although, in southern classrooms, the mean votes of satisfaction with daylighting was higher than northern classrooms.

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Good daylighting design in buildings not only provides a comfortable luminous environment, but also delivers energy savings and comfortable and healthy environments for building occupants. The importance of using daylight in educational buildings is because of the synchrony of operating hours of the school and daylight plenitude the sky. Daylight improves environmental quality and saves energy efficiency by minimizing artificial lighting requirements and thus reducing the cooling load. Window design is a primary sustainable approach in achieving environmental goals and contributes to comfort and satisfaction. This study analyzes the variations of annual thermal energy demand and useful daylight illuminance to determine the optimal Window-to-Wall Ratio (WWR) of a simulated primary school classroom in Tehran in two directions of south and north. Twelve different window sizes in two types of horizontal expanded windows (Height of the window remains constant, the width is varied) and vertical expanded windows (Width of the window remains constant, the height is varied) were compared in two parts, Useful Daylight Illuminance (UDI) and thermal and electricity energy, using Honeybee plugin of Grasshopper. Finding of this research reveals that vertical expanded windows are more energy-efficient in classroom while they give almost the same UDI as horizontal expanded window in both south and north facades. Generally WWR in the range of 25% to 35% in south façade has the best performance in daylight and thermal loads.

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Atrium is a popular architectural feature utilized widely by building designers and owners to bring various benefits such as adequate daylight, circulation spaces and surfaces for landscape applications. But atrium problems in tropical climates such as excessive daylight, glare and high temperature, which lead to increase building energy demand, have been reported. Atrium has been used with various shapes and purposes in many different climates and buildings especially public ones. It is mainly used to take advantage of daylight in buildings. Therefore, achieving the optimal atrium dimensions is of great importance. This research employed computer simulation using Ecotect and Radiance for daylighting. The collected database is created using simulations for different atrium proportions in IRAN-Qazvin climate zone, where using atria could improve building performance based on the clear sky condition. This research aimed to investigate various atrium models with the purpose of achieving optimal daylight. Note that a combination of factors contributes to calculation and reception of the optimal model including climate, use, and optimal daylight reception. Qazvin climatic conditions were simulated in Ecotect and Radiance. Ten 5-story administrative buildings with atrium ranging from 5%-50% area and one without atrium were modeled. The results showed that optimal samples were buildings with 10% and 15% atrium area in terms of daylight utilization. 
 

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For years, research on daylight in work environments with different climates has been important for researchers to distribute light evenly in the indoor space in order to create a healthy work environment and visual comfort. This study examines the effect of horizontal and vertical shading devices, the depth and distance of louvres on daylight with the aim of increasing DLA (daylight autonomy) for Abrisham tower in Tabriz, Iran. As input parameters the depth of louvres was considered 5 and 15 cm and their distance were considered 150 and 200 cm. Modeling was performed in Rhinoceros software and the Simulation was done in Grasshopper plugin to control the geometric parameters and with the help of ladybug and honeybee plugins. The multi-objective simulation tool, octopus was used to optimizing. Results show that vertical louvers caused more light reduction. Furthermore, the simulation effects of shaders parameter's include depth and distance being examined and analyzed, it seemed that the distance between louvers in this case and in Tabriz is more important variable and moreover, using reflective material or coating on louver’s surface as there are many weeks are overcasting theirs in Tabriz can help and improve internal light autonomy. The optimal cases that were obtained for north façade windows are horizontal louvres with a depth of 5 and a distance of 190 cm and vertical louvres with a depth of 15 cm and a distance 200 cm. In south facade are horizontal louvres with a depth of 13 and a distance of 161 cm and vertical louvres with a depth of 14 cm and a distance of 153 cm.

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The incorporation of various openings that permit daylight into interior spaces significantly influences thermal comfort. In the central region of Iran, Orosi windows are a prevalent architectural feature in courtyard buildings. These latticed door-windows are embellished with colorful glass pieces arranged in geometric patterns. This study aims to evaluate the impact of glass color in Orosi windows on their thermal and daylight performance. The primary objective is to determine the thermal comfort and daylight performance of a typical Qajarian Orosi with different glass colors (colorful, red, blue, yellow, green, colorless) and to identify the optimal glass color for Orosi windows. The findings reveal that the glass color of Orosi windows not only affects thermal comfort but also has a significant impact on daylight performance. Yellow glass offers the most favorable thermal conditions, irrespective of the season. In terms of daylight performance, all glass colors perform adequately; however, the Orosi with yellow glass achieves the highest values for spatial Daylight Autonomy (sDA) and Annual Sunlight Exposure (ASE). The next preferred options, in descending order, are colorless, green, and blue glass. Considering both daylight and thermal performance, it is recommended to use Orosi windows with yellow glass due to the 22% improvement in annual thermal comfort and satisfactory daylight performance.