Our client, “La communauté de communes du Pays Boulageois” launched an architectural competition in January 2010 in order to build simultaneously two childcare facilities: one of them in Boulay, for a gross floor area of 1000 m2 and the other one, fifteen kilometers further, in Piblange for a gross floor area of 350 m2. Despite the size difference between the two buildings, they both benefit from an open parcel and an urban context that imposes very few planning restrictions. We have thus chosen to explore this great contextual freedom and we have been therefore able to design these buildings by focusing on optimal functionality, safety and comfort, regardless of their size. CONCEPT Childcare facilities and nurseries are not intended for children but babies..., which conditions the behavior and the sensitivity of the parents and the staff. In our opinion, the infants’ fragility and need of protection and care should be taken into consideration and so integrated in the architecture. That is why we have chosen to develop a uterine concept, which has only been possible thanks to the unrestricted urban setting. FUNCTIONALITY The entrance is set back from the street and so from the traffic. In order to strenghten the visitors perception of feeling safe, it “submerges” into the building. We also have wanted to avoid dead-ends for the vehicle circulation, so the access is through a one-way lane that limits the parking maneuver and decreases the risks of accidents involving pedestrians, children or strollers. Moreover, the drop-off area is next to the sidewalk, so that the parents should never have to cross the street with children in their arms. We have organized the interior of the building around a highly protected circular central space. Children’s spaces gravitate and converge around this centre. Crossed views between each part of the building, are centrifugal and centripetal. The surveillance and the security are thus at the maximum level. At the very center of the building, the circus tent-like wooden structure ends with a 3 meters wide vaulted ceiling made of polycarbonate, which ensures that the daylight may be provided during the entire day. For the purpose of safety, the interior fittings have been designed in order to make all the right angles disappear and to offer smoothly curved walls. The sharp edges are also rounded off. The building is so characterized by this feature that even the external walls “undulate” around the internal spaces. Cardinal points are also taken into account during the design process of the buildings. As you can see on the axonometric views, we have indeed put together all technical and administrative spaces on the north side of the building, while saving the south side for children’s spaces. And the exterior spaces are, of course, south-facing. In order to provide children with a playground protected from sun or rain, which they can use regardless of weather conditions, the roof of building extends to cover these spaces. Another result of the centripetal organization is that, thanks to it, we do not need anymore hallways in these two buildings. Every children space is directly linked to central area. In addition to its aesthetic effect and ergonomic benefit, the real gain is related to space-saving. Thanks to this system, we have been able to save about 100 square meters, which gives a hallway ratio of 11 %. This benefit allowed us to design two buildings that respect BBC (Low Energy-Use Building) regulations without overrunning the provisional budget of our client. EXTERIOR SPACES Regarding the child-care facility in Boulay, it was the south-facing orientation and the natural incline of the site that gave us the idea of creating platforms with a cascade effect for a smooth integration with the environment. Each platform corresponds a function like gardens, playgrounds, educational gardens, etc ... The centrifugal shape of the facility reflects the situation of the site, which is literally surrounded by other educational facilities. Our building have neither a “main façade” nor a “back façade”, but as a circle that has only one edge, it has only one aesthetically homogenous façade, which can be seen from all around. Regarding the micro-nursery in Piblange, we have chosen to build on the flat part of the site, which is on the street side, so that the building would be south facing. Moreover, as the facility is at the entrance of the city, it plays a key role thanks to its dominant position and it requires particular attention for the façades’ design, like the child-care facility in Boulay. CONSTRUCTION MATERIALS Despite their atypical shapes, the both building have been designed to being built using traditional construction methods and materials. The facades are made of insulating clay bricks, covered by 20 cm thick re-enforced mineral wool external insulation. The external surface is covered with a classic coating and then painted according a pattern that we have determined. The internal surface is coated with plaster. The load bearing internal walls are made of reinforced concrete and they support the roof with glue laminated wooden beams that are curved shaped but mass-produced in order to decrease the manufacturing cost. A single layer damp-proof membrane covers the roof. The internal partition walls are made of double plasterboards, which are curved or straight. Perforated plasterboards cover the ceilings, improving overall acoustic comfort. The project also includes an under-floor heating system, covered by linoleum. Internal ecological paints are solvent-free. In order to reach BBC (Low Energy-Use Building) energy performances, the doors and windows are made of wood. TECHNICAL FEATURES AND ENERGY SAVING TECHNOLOGIES We propose natural gas-based heat production for the childcare facility in Boulay and a heat pump for the nursery in Piblange. HQE and BBC standards in France (HQE : High Environmental Quality ; BBC : Low Energy-Use Building) also require a high efficiency heat recovery ventilation system, which we have incorporated into the design and the estimation of the building’s cost from the outset of the project, as well as many other energy saving systems. We are aware that the calculations are pointless unless we actually deploy these systems, especially for the air-tightness of the building. That is why we have included to the construction process two blower door tests: the first one when the enclosure is completed, and the second one when the building is delivered to the client.