Even historic buildings can be successfully renovated for energy efficiency

The "Aerogel Architecture Award" was launched in 2020 by Empa and the industry partners Fixit, Agitec, Haga AG Naturbaustoffe, Hasit and the AdvaPor association. For the 2022 elimination, eight offices from Germany, China and Switzerland had submitted their projects. A jury consisting of the five experts Matthias Koebel (Switzerland), Ralf Kilian (Germany), Michael O'Connor (France), Volker Herzog (Germany) and Manfred Wehdorn (Austria) evaluated the submitted projects with regard to the value in terms of monument protection, energy efficiency and originality of the chosen solution. In each case, the renovation uses so-called aerogels, highly porous solids in which up to 99.98 % of the volume consists of pores. They require little space and are very flexible. Aerogels are therefore used where conventional insulating materials are not possible, for example in listed buildings.

First prize for a UNESCO World Heritage Site

The award ceremony took place at NEST, the research and innovation building of Empa and Eawag. The winner was an impressive project from Darmstadt, which was designed by the architects' office schneider+schumacher is being realized. This is the refurbishment of the unique exhibition building on the Mathildenhöhe, which has been a UNESCO World Heritage Site since 2021. In addition to modern glass that allows controlled use of daylight, a new type of high-performance mineral insulating plaster made of aerogel granules is being used in the outer shell of this historic building. This will significantly improve the energy quality of the facade, according to the statement. In the future, better use will also be made of the site's conditions, for example by using the historic water reservoir under the exhibition building to store energy.

Reduce energy consumption step by step

In second place was the Heilig Geist parish in Zurich. The center includes a church, community rooms, offices and apartments and was opened in 1973. The fact that little attention was paid to building insulation at the time was evident from the parish's high energy consumption. Over the years, architect Beat Kämpfen of Fighting Zinke + Partner The company therefore implemented various measures to optimize the energy efficiency of the building. These include, among other things, several solar systems on the entire grounds, the use of aerogel in the façade, and a replacement of the gas heating system with a heat pump system including geothermal probes. It was always important that the external appearance of the parish remain as unchanged as possible. Thanks to the innovations, the center received the Minergie certificate in 2020.

Renovate historic buildings for energy efficiency while preserving their appearance

Third place on the podium goes to a building in Winterthur. The house on Lindberg was built in 1963 and has been systematically developed over the years without changing the basic structure. This was also the requirement that the client placed on the team around the architect for the renovation of the outer shell. Anne-Kathrin Halt. This meant that, among other things, the volume of the building could not be changed and various elements, such as a ceramic relief on the wall of the house, had to be preserved. For this reason, it was decided to insulate the villa using aerogel panels. To do this, the existing trowel cast, including the base plaster, was first stripped down to the masonry. The exposed volume was filled with 20 mm wide aerogel panels, the trowel throw was reapplied and the original exposed concrete structure was reconstructed.

Source and further information: Empa