Djurdjevic Architectes Djurdjevic Architectes
007 Maison de l’enfance, Yverdon-les-Bains
1. Mention, 3. Rank

Type of mandate: Open competition
Client: Etablissements Hospitaliers du Nord Vaudois (eHnv)
Study period: 2023
Budget: 15’000’000 CHF
Built surface: approx. 11’200 m2
Project perimeter: approx. 6’800 m2
Programmes: Daycare, Parking

Architecture: Djurdjevic Architectes, Lausanne
Muriz Djurdjevic
Structural engineer: co–struct, Aubonne
Fabrice Meylan, Sam Bouten
Mobility engineer: Team+, Lausanne
Pedro de Aragao, Stéphane Menoud
Images: Ferala, Basel

The heart of the block as a foyer

The plot is treated as an open block where the architectural rules aim to generate unity in diversity for the new neighbourhood. The project proposes two compact volumes articulated at the northern and southern ends of the plot in order to propose a generous and densely planted central space, the heart of the block. The unitary treatment of the courtyard makes it an identifying element for the block. The flowery meadow-type covering and the dense planting of large trees associate it with the vocabulary of Yverdon parks such as the Parc d'Entremonts or the Parc des Thermes. The canopy is composed of local deciduous species that filter the sunlight in summer and guarantee sunshine in winter. Generous public paths wind between the volumes and allow access to the buildings to be linked efficiently. This piece of town thus fits perfectly into the urban morphology of Yverdon, where green spaces wind their way between the buildings and play an essential role in the quality of life of the inhabitants.

Permeability of spaces and soil

The future green promenade of the hospital complex is called to become a major axis of soft mobility linking the thermal centre, the hospital and the future heart of the block in the way of a pearl necklace. By walking along this avenue along the plot, the passer-by is invited to the interior of the latter by openings between the volumes allowing a glimpse of the heart of the block and the plant fresco of the south façade of the car park. This permeability also allows for visual continuity across the plot as well as soft mobility through a weak structure connecting to the adjacent plots. This open area allows both wildlife and humans to move freely. In the block, particular attention is given to the floors and their surfaces. These are transformed to fulfil many roles. They mainly allow the infiltration of all rainwater. The permeability of the soil is favoured and the use of mineral surfaces is reduced to a minimum. The water thus infiltrated on site is stored in the soil all year round and directly benefits the flora, for which the abundance of water allows for better growth, better resistance to climatic hazards, and refreshes the air during the summer heat.

Compact and bright volumes

The project proposes two compact volumes with minimal façade spread to reduce heat loss and guarantee maximum sunlight within the interior spaces. The parking building is located at the corner of Rue de l'Hôpital and Rue de Gasparin. It follows their alignments and thus creates a strong front in the axis of Rue de Gasparin. The entrance to the car park is thus easily identifiable and guarantees clear access to the motorised flows from the depth of the future avenue. Two stairwells in the façade provide easy and rapid access to the hospital, the heart of the block and the Maison de l'enfance. These bright circulation spaces, open to the surrounding landscape, offer a sense of security to users and are easily identifiable from a distance, thus guaranteeing efficient pathways. The rounded corners of the car park volume accentuate the volume effect of the building while entering into dialogue with the architectural expression of the future hospital. The Maison de l'enfance is located to the south of the plot, following the orthogonal alignment of the buildings in its direct context, Le Lierre and Plaisance. The clearance thus provided allows for the creation of a drop-off area for parents as well as a large shaded bicycle parking area.

Durable and warm materials

The structural framework of the car park is simple and regular, both in plan and in elevation, working with a grid of precast prestressed concrete columns resting on precast pillars. The large span of these pillars allows for flexibility in the use of the space, for the car park or for any other future use. The floor is made up of a mixed wood-concrete modular slab: a prefabricated concrete slab rests on locally sourced squared timber joists. This system reduces the ecological impact by about 30% compared to a purely reinforced concrete or steel system for such structural spans and the factory preparation of the elements reduces the construction time. The spatial quality generated by the use of wood in the underside not only reduces noise pollution but also offers users a warm atmosphere rarely seen in a car park in Switzerland. In addition, all parking levels are naturally lit and ventilated. For the foundations, with the presence of the water table, a recycled RC-C concrete is used for the invert and the footings. In the Children's House, the principle is identical: a mixed wood-concrete floor resting on prefabricated concrete crossbeams. The pillars are also prefabricated and rest on in-situ concrete foundations.

Systematic and repetitive support system

The two structures are designed on the same principle of joists that support a mixed floor. A slab rests on joists and the connection is guaranteed by notches that will be filled, once the elements are in place, with a sealing mortar embedding the connecting reinforcements. This system makes it possible to separate the wood and the concrete during assembly, thus reducing the loads at the end of the crane. In the Children's House, the beams are only transverse and rest on 4 pillars spaced at regular intervals. In the car park, the beams form a grid that allows the floors to be cantilevered along the building's facades and reduces the number of pillars to a minimum. This balances the loads and optimises the structure. The large spans also allow the number of floating piles to be reduced to limit the impact on the protected geological layers and the water table. The mixed floor is designed to horizontally brace the plane and the structure is then stabilised by the vertical circulations, which are connected directly to the windchests, and the loads are thus brought back into the ground.

A safe and quiet place

The Children's Centre programme has particular needs in terms of safety and well-being for the children, which are difficult to imagine in too close proximity to the car park; a programme which, despite all the attention that can be paid to it, involves certain noise pollution and a risk linked to cars. The decision to separate these two programmes into two separate buildings allows the children to spend their days in safety and confidence, while offering the professionals ergonomic and favourable working conditions and the parents the feeling of leaving their children in a safe place for the day. Flexibility, simplicity and mobility are the watchwords for the design of the Children's Centre, which is built around a central common space, the foyer/refectory, which is generous and luminous thanks to its double height, and around which the separate spaces dedicated to the different groups of children are built.

Shaded outdoor spaces

The Children's House is presented as a pavilion in the green park. It has a large outdoor space protected all around by a barrier making it inaccessible and not allowing children to leave. These outdoor spaces are shaded in summer by the canopy of the surrounding trees and by the eaves/courtyard, giving the children the opportunity to play outside while being protected from heat stroke. This arrangement allows them to run, jump and climb on the garden facilities while being easily supervised by the Maison de l'enfance staff. As the children in the nursery group (4-30 months) are the most vulnerable in hot weather, an outdoor space to the north allows them to go out and play while benefiting from the additional shade provided by the pavilion itself.

A generous and welcoming foyer

Ideally located in the centre of the building, the entrance sequence allows access on the Rue de Gasparin side and on the heart of the block. Children and employees of the Maison de l'enfance will easily find their way through the foyer, which serves the entire space and has a real unifying function. The foyer acts as a generous covered public square with its double height facing west and open to the green outdoor spaces. As the youngest children in the nursery group (4-30 months) and the trotters (2.5-4 years) are the least autonomous and mobile, their living spaces are located on the ground floor with full access to the outside where they have generous shaded play areas. The older children (4-6 years old) are located on the first floor. They have two gently sloping staircases allowing the children and staff to access the outdoor play areas in complete safety. The 3 children's living areas are thus clearly separated and have their own entrance from the foyer. The spaces dedicated to the staff are mainly located on the first floor and have a large break room that can be subdivided for events such as conferences or internal training. A clear separation between spaces accessible to children and spaces dedicated to staff is thus offered in this plan.

Ergonomics and flexible organisation of spaces

The plan is characterised by its rationality and efficiency. It is based on an optimal structural grid for educational space allocation while minimising the number of load-bearing elements. The children's living spaces are dimensioned according to an open plan without fixed partitions in order to allow the spaces to be reorganised with the help of sound curtains according to the activities carried out there and the age of the children. In such a place, children play, learn, sleep, eat and experiment with each other. It is therefore a constantly changing environment, which is transformed to adapt to the activities, some of which take place in the same place but at different times of the day. The facilities are therefore designed to support the children in revealing and structuring their potential, and to enable the educational staff to accompany them with flexibility and kindness. The choice of natural and bio-sourced materials, beyond the sustainable construction considerations already mentioned, offers a natural and healthy living environment for the children and the educational staff.

The eaves/roofs are sized to allow maximum natural light and solar gain in winter. The sun fully penetrates at midday on 21 December, allowing the energy from the sun's rays to be absorbed and transformed into heat inside the building. This reduces the energy used for heating. In addition, thanks to the mass of the mixed slabs, the building retains a good inertia which dampens the day/night temperature variations. In summer, the eaves act as a sunshade, preventing the rays from penetrating the building. Canvas sunshades fixed to the outside of the glazing allow a finer adjustment of the natural light in the work spaces. The greening of the building and exterior spaces further reduces surface temperatures by reflection of solar radiation and evapotranspiration of the water contained in the plant substrate. Green roofs allow rainwater to be collected and promote biodiversity.