DAYLIGHT IN GENERIC CLASSROOMS OF SECONDARY SCHOOLS - COMPUTATION VERSUS USER Jaroslav VYCHYTIL **, Martin VYCHYTIL ** CTU in Prague, Faculty of Civil Engineering, Department of Building Structures

INTRODUCTION People spend most of their lives in buildings. Designer must therefore take into account all the factors which are made on the spaces. Satisfactory daylight has a positive effect on the psychological and physiological state of our organism. Daylight must be used in interiors with permanent residence of people as much as possible. Conditions for healthy visual comfort, good vision of the observed objects, prevention of premature and excessive visual fatigue and prevent the possibility of injury due to impaired eye sight must be created daylight.

What is Generic Classrooms? classrooms with permanent residence of people (pupils) more than 4 hour per day and together (at the same time) more than 1 day a week

Restrictions of the Research Only tipped secondary schools were selected for the purpose of this research. Why did we restrict to secondary schools? pupils aged 15 and older pupils who already have some opinions This is a prerequisite for under standing the questions referred and their correct answers Do you know what is the Highlands? Sausage … ?

Restrictions of the Research Which secondary school was chosen in the end? - from different locations and different-sized towns and cities - 2 classrooms were selected in every school - different conditions shielding (the first classroom shielded if possible, the second classrooms unshielded), - different orientation to cardinal points (because of the potential glare) etc.

Computation Evaluation We numerically evaluated a total of 10 classrooms in 5 different secondary schools (for now). All the selected schools were located in old buildings. This is related to some problems: The requirement for minimum daylight factor has not been met in most classrooms. This is not surprising, because it was a large room depth (up to 7 meters) and the high window head jamb. The uniformity ratio of illuminance was satisfactory in mid-evaluated classrooms.

Illustration of Evaluated Classrooms the high window head jamb

Illustration of Evaluated Classrooms ground plan: a large room depth (up to 7 m) and the high window head jamb.

ground plan: dividing line 1.5% for permanent residence: plastic window with large area of window frame

Questionnaires Problem: Teachers are limited educational documents. They must explain particular curriculum. They did not want to lose time.

Questionnaires For now, 232 of pupils expressed in questionnaires to the level and the quality of daylighting of their classrooms. 4 hypothesis verified. The form of the questionnaire was chosen because of the relative simplicity of processing the data received. Questionnaires were distributed in printed form with the direct participation of the authors. The pupils declare on 20 questions in total. We have obtained many opinions, depending on the age, sex, condition of sight etc.

Hypothesis 1 The pupils are convince of the need and important of daylighting in classrooms. However, their informing about the importance of daylighting is lower than for other disciplines of building physics. - CONFIRMED More than 93% of pupils are convinced about the importance of daylight. Almost 75% of pupils think that the insufficient the quantity and quality of daylight have an effect on their health. Almost 54% of pupils think that they are informed about daylighting the least. 41.83% of pupils think that they are informed insufficiently about the importance of daylight.

Hypothesis 2a The pupils preferring cold shades of colours, evaluate the quantity and quality of daylighting more favourably than pupils who prefer warm shades of colours. - DISPROVE It depended on whether they could decide on the colours. Almost 90% of pupils like colours. 63.27% of pupils prefer warm shade of colours. Less than 30% of respondents had no objection to the shades of colour in their classroom. Almost 82% of pupils considered their classroom as colour neutral. Most pupils with a preference for warm colours stated that they are dissatisfied with the colours in all evaluated classrooms.

Hypothesis 2b The pupils preferring cold shades of colours, evaluate the quantity and quality of daylighting more favourably than pupils who prefer warm shades of colours. - DISPROVE The pupils, who prefer the cold shades of colours, expressed their views on placement of furniture almost evenly in all scales of assessment. Most of them stated that their place of visual activity is illuminated sufficiently. Pupils who prefer cold colours are more benevolent only in the evaluation of the performance of distributing light effects.

Hypothesis 3a The pupils writing with their left hand, evaluate the level and quality of daylighting worse than pupils writing with their right hand. - DISPROVE They are used to it since from the first class. These pupils can shade their hands while writing notes. The usual direction of incidence of light on the work surface is from the left side.

Hypothesis 3b Around 56% of all pupils (53.85% of pupils writing their left hand) are satisfied with the suitable positioning of furniture, at least a bit. 12.24% of all pupils (7.7% of pupils writing their left hand) are dissatisfied with illuminance of place of their visual activity. 15.31% of pupils are at least partially dissatisfied with the direction of light incidence. If we restrict to pupils who write with their left hand, a third of them are dissatisfied.

Hypothesis 4a The pupils sitting further away from windows evaluate the level of daylighting worse than pupils sitting by the windows. - CONFIRMED Classrooms are often profound. Light intensity decreases with distance from the window. necessary to restrict depth of room, height window head jamb

Hypothesis 4b The pupils, who are sitting in the row by the wall, are satisfied with the placement of furniture in two thirds of cases, at least partially. Over 56% of pupils are satisfied when we take into account pupils in all places. What do pupils think about adequate lighting place their visual activity? 12.24% of all pupils are dissatisfied. If we restrict on pupils, who are sitting in the row away from windows, 17.86% of them are unsatisfied. We reach similar result when we asked the questions on directivity of light.

Thanks for Your Attention You write for more information on e-mail jaroslav.vychytil@fsv.cvut.cz