Eight-storey record

As cities continue to grow, the demand for high-quality and affordable housing in dense urban environments increases. Vienna is no exception. In fact, the biggest city in Austria is in dire need of affordable housing. In Vienna’s 12th district, a residential area of almost 11 hectares was completed in 2024. Called the Wildgarten, the land is filled with buildings and projects of all scales: from two-family homes to multi-storey apartment buildings. Today, 2,300 people inhabit the 1,100 housing units.
 
Marking the end of the multi-stage construction phase, the last 14 residential buildings were erected between 2023 and 2024 and all 14 of them were planned in monolithic clay block construction. Two of these buildings are eight storeys high, setting a record – the world’s first high-rise monolithic clay block building with integrated thermal insulation, where the entire load-bearing structure is made of ceramic masonry.

For these 14 buildings, a total of over 205,000 clay blocks were used. The architect’s aim was to treat the material with the utmost respect: architects and developers designed the buildings in a way to minimize cutting. “In the vertical direction, the distance between the top and bottom edges of the raw ceiling is 2.77 m for all houses – this corresponds exactly to 11 blocks heights”, says Gerd Pichler, Head of ARE Project Development. The two eight-storey residential buildings in Wildgarten impressively demonstrate how versatile and efficient clay blocks are, even at lofty heights. Apart from its innovative aspects, Porotherm W.i creates the pleasant indoor climate of familiar clay block walls and supports the thermal performance of the building envelope.
 
The two eight-storey residential buildings prove that clay blocks are a robust material that meets modern demands and is convincingly practical in constructing the sophisticated high-rise buildings of our time. To check the load-bearing structure in advance, a special software was developed: Based on a program for calculating reinforced concrete and timber structures, it was adapted to perform complex calculations for ceramic masonry.

Considerations relating to material use, construction methods and building performance led the architect and developer to avoid a conventional external thermal insulation system and instead insulate the houses with Porotherm W.i. The ceramic blocks integrate thermal insulation made of mineral wool directly within their cavities. The built-in insulation is integrated into the wall system, eliminating the need for an additional external thermal insulation composite system in this project.
 
With its integrated insulating filling, Porotherm W.i clay blocks provide thermal insulation within the wall construction while keeping the external wall relatively slim. “Thanks to their material structure, clay blocks can store and release heat,” explains architect Eckehart Loidolt. The Wildgarten project reflects an approach that considers material efficiency, durability and long-term use, with Porotherm W.i forming part of this concept.