Order´s origin is the design of an economic housing for a family of middle class placed in the bland environment of the Cintruenigo's semi-urban periphery, a small nucleus of population in the interior of the Iberian peninsula where one of the major indexes of sun hours by year is registered. In spite of treating itself like usual and standard case concerning type, program and dimensions, we have tried to avoid the habitual topics and, on the opposite, thinking, from sustainable construction criteria, about different functional, typological and technological possibilities that offers actual days. investigation goes on optimizing the interchange that takes place across the skin of the building, fundamentally focused in energetic criteria. According to that, we propose to assign this skin a dynamical quality that allows it to modify its configuration in order to adapt the changeable thermal and reological exterior conditions. The constructive reference will be the Mediterranean window based on its optimal functioning and versatility. The traditional window establishes several parallel filters to modify its relation with the exterior, and combine them to regulate lighting, thermal, acoustic conditions and safety control. Nevertheless it supposes a discontinuity in the wall, which hits front to the modern movement: the wall has turned into window. We try to establish an intermediate position: inspired by the master classes of the tradition, but working into the technical and ideological progress. The exterior aspect that the housing presents is a consequence of the rigorous modulation of the industrialized elements that form it. Opaque, translucent, or transparent, there are generated big modules by this way, that create a material, colour and texture mosaic skin, inside a very defined family. This versatility offers different and varied forms of utilization and enjoyment of the housing depending on the movement and the sheen of the sun, the moment of the day, the station of the year and of any phenomenon and circumstance that affects the building.