ZPF Ingenieure

After 130 years without any noteworthy structural interventions, the St Leonhard schoolhouse in the St Gallen neighbourhood Davidsbleiche had to be renovated and spatially adapted to the changed school concept. To retain the structure of the historical schoolhouse, all its uses that required a lot of space were transferred to the new building. A sophisticated interplay between the St Leonhard schoolhouse and the new building was achieved by means of the latter's clinker facade, positioning and form, thus strengthening the complex as a whole, with the schoolyard as the centrepiece.

In the historical schoolhouse, which is listed by the city of St Gallen, all surfaces and installations were renovated in keeping with environmental guidelines, except for the wooden panels, the rooms' doors and the radiators. The schoolhouse facade was repaired and now radiates its former glory anew.

The new building accommodates the day-care facility, with a professional kitchen and multipurpose hall on the ground floor, west and east of the central stairwell. The two-storey single gymnasium and changing rooms are situated on the first floor. On the second floor, above the changing rooms, there is a bright walled outdoor playground, accessed via a separate stairwell. A former civil defence installation, links the buildings underground, while also providing storage space and exercise areas for the day-care facility.

The new building stands on this pre-existing shelter, as well as on a new concrete framework based on micropiles and screw piles. Bracing is provided by shear walls and the central infrastructural core, all made of in-situ concrete.

The reinforced-concrete facade on the ground floor is seamless and supports the upper floors' clinker facade, which is also seamless. The exterior walls have a double skin, with an inner concrete wall, a 20 cm insulation layer and the outer clinker facade. The light-flooded gymnasium is spanned by prefabricated concrete beams.