A design approach for daylight utilization in typical school classrooms

Good learning environment promotes better learning. A well designed school environment encourages students for learning, increase students' performances and shape their perception about the society they are in. Schools must satisfy physical and psychological needs and expectations of children. For all the reasons mentioned above, schools must be designed very carefully. The concept of typical project provides fast and easy production. However typical projects create outmoded and standardized projects. The application of typical project concept in primary school buildings where educational activities performed create spaces that can not fulfill needs and expectations of children. Visual activities like writing and reading are carried out in educational buildings and appropriate lighting conditions must be achieved in order to perform these activities accurately, precisely and quickly. Optimum use of daylight in classrooms has number of positive effects such as ensuring visual comfort, better health conditions, better learning environment, encouraging children to outperform in schools, also energy saving by reducing the demand for artificial lighting. The aim of this study is; • Daylighting analysis of primary school classroom designed by following the design guide criteria prepared by Ministery of Education of Turkey, • To demonstrate design alternatives for better utilization of daylight in typical elementary school classrooms, • To demonstrate the possibility of presenting simple but effective design solutions for improving daylight performance of classrooms that faces different directions. In this study, design criteria for effective utilization of daylight in classrooms are discussed and design alternatives are developed for classrooms in typical primary schools. Appropriate solutions are determined by comparison data obtained from the simulations following the criteria in standards. The study consist of six chapters. The purpose, scope and methods of the study is mentioned in Chapter 1. The concept of education and typical projects are discussed in Chapter 2. Historical process of primary education system in Turkey is reviewed. Information about the concept of typical project is discussed and disadvantages of using this concept in educational premises are stated. Historical process of typical project concept in Turkey is also reviewed in this chapter. The concept of lighting and visual comfort are discussed in Chapter 3. Parameters affecting visual comfort are described. Illuminance, uniformity, glare, luminance, color aspects are described and recommended values for these parameters are given according to the data gathered from the standard of EN 12464-1. Concept of daylighting is discussed in Chapter 4. Positive effects of daylight on health, performance and child psychology are argued. Studies conducted to demonstrate these positive effects are introduced in this chapter. Design parameters affecting the daylight performance of a building are explained. Each parameter was explained according to the issue of daylight utilization in elementary schools. These parameters are classified in 3 groups as it follows: • Parameters related to the environment of the building, • Parameters related to the building, • Parameters related to the indoor space. Methods for introducing daylight into a space are also discussed in this chapter. These methods are classified in 6 groups as it follows: • Sidelighting • Rooflighting • Atriums • Glazing • Light pipes • Light shelves • Shading devices In Chapter 5, a typical classroom is designed in accordance with the design guide criteria prepared by Ministery of Education of Turkey. In the scope of this study, daylight factor, illumination level and uniformity ratio are examined. For daylight factor, simulations are carried out for overcast sky conditions. For daylighting simulations, 21 st of March is selected as representative day, and 9.00 a.m., 12.00 a.m. and 3.00 p.m. are selected as representative hours. Daylighting simulations are carried out at average sky conditions on 21 st of March, at the time of 9.00 a.m., 12.00 a.m. and 3.00 p.m. respectively. All simulations are performed for İstanbul, representing the temperate climate region. Daylighting simulations are performed by using Dialux Evo 7 programme software. The simulation results showed that the required level of illumination for visual comfort and the daylight factor value for a daylit classroom can be achieved by following the design guide criteria prepared by the Ministery of Education of Turkey. Although the required values for illumination level and the daylight factor are provided, it's been determined that the illumination was not uniformly distributed since direct sunlight was not obstructed. For this purpose design alternatives are developed in order to ensure visual comfort in classrooms. To ensure facade integrity and the solar control, same type of adjustable shading devices in south, east and west orientation are proposed and using light shelves uniform distribution of illumination is aimed. Simulations are made for each scenarios and appropriate alternatives are identified by comparing. Findings are; • The direct sunlight is to be obstructed by using horizontal shading devices that provide 45 profile angle in south facing classrooms. Values for illumination level and the uniformity ratio is provided by using this scenario. • For the classrooms facing east and west directions, due to the changing angles of sun it is recommended to adjust the inner parts of the shading device. Also it is recommended to use manual devices inside the classrooms during morning hours in west facing classrooms and during afternoon hours in east facing classrooms. Conclusions of the study are discussed in Chapter 6. Recommended scenarios for each directions and for representative hours are given in table. The contribution of the study and topics that can be examined for future studies are also identified in this section.