The dwellings are organized by a flexible and multifunctional form about a central core of baths that allows natural crossed ventilation while transverse views of the house. A second skin of translucent white laminated glass in south facade works as a solar filter generating qualified intermediate, luminous, ethereal spaces... agreeable and comfortable. His first totally glazed skin slips from being a limit to become an extension from the interior towards the exterior.A communicative building with and unitary treatment but simultaneously neutral, superposes the successive skins generating multiple and changeable reflections of unexpected opaqueness creating atmospheric effect... frivolously and vaporous... reflections on the white glass of the sky, the clouds, the sun... extreme delicacy, formal austerity, rigor, eco efficiency, prefabrication, efficiency, exclusion of everything superfluous, purity, neutrality, absence, emptiness, silence, fluency, to non-be, absence of architecture, nothing , to develop imperceptibly.The building is organized by two communications center that serve two and three apartments per floor. To achieve the area there are two typologies, one oriented north-south with bathrooms in the centre and the other one faced to one facade with water area located inside. The first one has crossed ventilation through opposite fronts, while the second one also have transverse ventilation with perpendicular facades.The building is designed with a strong directionality and adjustment to the climatic demands of each facade. The east and west facades are smaller and are treated with small windows that allows crossed ventilation to living-rooms, bedrooms and also bathrooms. The north facade is provided with longitudinal balcony, to allow great views in each room. The south facade opens itself completely to the magnificent views while using a second skin of translucent white laminated glass that slides along the whole facade, can boost profits and reduce energy losses according to the requirements of the seasons and the users at a time that a free, dynamic, flexible and light composition, provides the mobility and adaptability.During the night the facades are transformed into a lamp providing of sifted light, porous and levity that generates and urban milestone.The main feature is the large amount of natural light thanks to the generous dimensions of the balconies as well as the provision of access to the terrace from any room.The bathroom, situated in the centre, have two entrances to connect to different bedrooms meanwhile allows constant movement and crossed views and ventilation from north to south.The kitchen is fully equipped with an area used for cooking distributed in a bar, dining area for functional and practical always located in a privileged space to the front facade and terrace with direct access to communicate directly with the dining room through a door sliding glass large that expands and enlarges the space under the living room. Finally, the area for cleaning, laundry and storage area complete the kitchen.Located in a continental climate is marked by contrasts in temperature between day and night and summer and winter, and conditioned by the orientation from west to east. We considered protecting and isolating the fronts north, east and west, while leverage and distribute strong gains energy from the south to the interior.Our main strategy was on one hand was achieved energy from the south facade and on the other side exploited and worked to spread the gains in all rooms. The south facade was provided by a gallery comprised of a fully double glazed sliding skin, the inner and outer transparent translucent facades system, adaptable, flexible and multifunctional.The dwellings are organized around a central core of baths zone that allow circular route around them, while allowing the natural crossed ventilation.CRITERIA OF SUSTAINABILITY AND ENERGETIC EFFICIENCYA second skin of 5+5mm laminated glass translucent in south facade works as thermal skin in winter and suncreen in summer.In winter daytime outdoor slides open to let in solar radiation heating the concrete mass with high thermal inertia, and closing at night by irradiating the mass, which in turn is enhanced by heating underfloor water. In summer the outdoor runners close and open the interior while at the same time the exterior windows of the north facade are open getting natural cross ventilation, no waiver to day light.A good insulation of solid parts, the thermal break in all woodwork including window frames, pillars, along with the generation of hot sanitary water with solar panels in the roof, minimizes energetic consumption.The insulation of the separating walls between entities and between the rooms in the same housing guarantees the rest and the conviviality.The functionality and space optimisation that allows sliding system applies throughout the building from the facades, up to the internal divisions that are integrated sliding partions. This allows a great spatial flexibility, freedom of movement and of distribution, providing a clean, fluid, flexible space and above all adapted and accessible overcoat to all.On the other hand the centralization of the water zone simplifies and minimizes the tour of the facility as well as it allows complete freedom for rearrange the rooms. The organization and optimization services produced by the stairwell where through the lobby ceiling plant community goes into every house and distributed through the ceiling into the water area and kitchen.