Erected as an ecological pilot project in the midst of a residential area, the kindergarten accommodates three groups. The compact, semicircular layout ensures a balanced relationship between the area of the façade and the overall volume. The lightweight, transparent form of construction of the external walls facing the sun facilitates the passive use of solar energy and its storage in the interior: in the floor slab, which is thermally insulated on the underside, and in the partially solid internal walls. The solid north and west walls, 24 cm thick with a 10 cm layer of mineral wool and timber cladding on the outside, also reduce temperature losses.