Single-family home Aiterbach, Germany

Fifty cm-thick outer walls with a bulk density of only 700 kg / m3: the path to completing this concrete home presented a welcome challenge for everyone involved.

There is an attraction radiated by any successful aesthetic design. And, the resulting demand explains why, for instance, the popularity of concrete floors – or even exposed concrete buildings – has grown in recent years and now encompasses residential construction. Such a trendsetting project was recently completed in Aiterbach, Upper Bavaria, Germany. The two-storey home draws in the gaze of everyone who passes by: a minimalist monolith, whose massive upper section elegantly rises over the rolling landscape – seeming almost to float. The simple, timeless design by builder and architect Michael Thalmair is more than just eye-catching. It is unique in at least one other important respect: the 50 cm-thick outer walls are made of infralight concrete, giving them a bulk density of only 700 kg / m3.

The lower level of the hillside home has a conventional construction, using 24 cm walls of waterproof reinforced concrete with XPS insulation. For the monolithic structure of the upper floor, Michael Thalmair had something wholly different in mind: massive 50 cm walls of infralight concrete – a modern high-performance building material that offers a pleasing mix of stability, sustainability, insulation, and smart elegance. Getting the mix right, however, takes a great deal of experience and know-how, and special permitting is required for any application of infralight concrete. This is why architect Thalmair and his contractors at Adldinger chose HeidelbergCement’s subsidiary Heidelberger Beton, and concrete consultant Björn Callsen from Munich. The first tests were conducted at the Heidelberger Beton laboratory. The next steps in the process involved concrete consultant Callsen engaging experts from Bundeswehr University Munich (UniBW), together with Professor Karl-Christian Thienel, to assist with the project.

The energy balance of the new home is an added benefit: a heat pump and central fireplace are used to keep the dwelling comfortably warm in cold weather. The high insulation value of the infralight concrete means that heat is captured and stored in the concrete, and slowly released back into the rooms.

The single-family home in Aiterbach is practically free of seams in the concrete face. This makes for a smooth and impressive structure, and opens new vistas of design potential.

Infralight concrete from Heidelberger Beton allows builders and architects to pursue highly individualised designs for generously proportioned and extremely energy efficient buildings. And, because the material is 100% recyclable, infralight concrete is an ideal choice to create visually attractive architecture for a sustainable future.

context 01/2017

85391 Aiterbach