The path of the summer sun from northeast to northwest traces the cut of the slope. The slope angle offers the best sun exposure to both the slope and the courtyard from the south and west. Underneath the slope forms an unheated space where a forest of columns is used for swings and other forms of play, when the weather is cold or wet. Two other light wells cut into the roof plane ensure daylight and a variety of outdoor space in conjunction with the other rooms of the building.
The building design is the result of the authorities' planning regulations and the call for the greatest possible connection between the outdoor areas of the ground and roof plans, taking optimal advantage of site’s sun orientation. The building consists of two planes which extend to the boundaries of the site. One plane forms the ground terrain covering the contaminated ground, a second forms the roof. The ground terrain surface is folded upwards in such a way that it forms a hill or slope between the ground and roof.