Extension for Kunstmuseum, Basel, Switzerland

An expressive new building was added to the Kunstmuseum Basel, extending the existing exhibition space in the Christ-Bonatz building by almost 3,000 m². The new building is connected to the main building underground. The core-insulated perforated facade made of concrete and silver-gray brickwork with LED frieze is particularly notable.

Transsolar advised on the development of comfort, ventilation and energy concepts for the compact building. Particular attention was paid to the requirements for humidity and temperature, since art museums have very strict curatorial requirements to be considered for protection and preservation of the artwork.

The ventilation concept was developed for the specific ceiling construction and adapted for the works of art in such a way that it ensures temporally and spatially constant temperature and humidity conditions at extremely low dust levels. In addition, characteristic building load curves were generated, which reflect the future energy requirements of the building for heating and cooling. The comfort concept includes thermally activated, raised solid floors with parquet flooring, which can be heated as well as cooled.

The fresh air is supplied to the room via the ceiling with minimal turbulence. Its temperature is slightly lower and results in an ideal mixing ventilation for the room, preventing temperature and humidity coatings in the room which would be harmful to the artwork. The exhaust air is also discharged through the ceiling. Together with a special ceiling construction, this allows the consistent removal of the convective heat loads of the UV-free artificial light, without thermally stressing the rooms. The comfort and ventilation concept was validated by flow simulations and a final measurement campaign in a real-life functional mock-up of an exhibition space. A similar ventilation concept was implemented in the Christ & Gantenbein extension to the Swiss National Museum Zurich.

The museum is connected to the Basel district heating network and thus obtains the required heat with a very low carbon footprint. If possible, cooling is done by free cooling and, if necessary, by mechanical cooling. Sorption wheels recover latent and sensible heat from the exhaust air, whereby the air exchange rate is controlled depending on CO2 levels. The maximum rate is two air changes per hour. When the museum is not open to the public, recirculation regulates the indoor air humidity.