4a Architekten GmbH

4a Architekten GmbH – founded in 1990 by Matthias Burkart, Eberhard Pritzer (until 2001), Alexander von Salmuth (until 2018) and Ernst Ulrich Tillmanns – stands for architecture that creates atmosphere, conveys values and lends identity. Influenced by the Behnisch school, the architects have been combining design excellence with functional clarity for over three decades – and consistently focus on sustainable concepts. Today, Matthias Burkart, Ernst Ulrich Tillmanns, Andreas Ditschuneit and Martin Reimer lead the 45-strong team. In addition to its headquarters in Stuttgart, the office has also had a location in Munich since the beginning of 2025.

The firm has made a name for itself in spa construction in particular – with buildings that have a strong identity and are inspired by their location, people, and context. This results in projects that are clearly designed, authentic, and long-lasting. Open, interdisciplinary collaboration combines creative power with construction expertise. The result: the highest quality and sustainability. Over 30 completed swimming pools constructions – including the Therme Wien and the Therme Lindau – characterize the portfolio; more than twelve others are currently in planning or construction. At the same time, 4a Architekten convince in “building in existing contexts” with renovations and extensions, including listed buildings such as the Kurbad Königstein im Taunus.

4a Architekten designs building culture with attitude – characterized by lightness, informality, and a deep sense of responsibility. Well-thought-out constructions, durable materials, and sustainable energy concepts combine atmospheric design with functional clarity and economic aspects. This creates places that touch people, promote community, and will endure for future generations.