Reconstruction Begins
The Prager’s Cubes complex in Emmaus is about to undergo its most significant transformation since its completion in 1973. The reconstruction, which began in July 2026, will carefully restore this important modernist complex designed by architects Karel Prager and Jiří Kadeřábek, preparing it for decades of future use. The work will take approximately three years and require an investment of around CZK 1.4 billion.
the significance of Prager’s Cubes
Prager’s Cubes represent an enduring part of 1970s architecture. At the time, Karel Prager's structural concept was among the boldest in Czechoslovakia. The construction of the three floating pavilions also employed the GAMA modular building system—specially adapted prefabricated panels, parapets, partition walls and suspended ceilings. Together, these elements created a remarkable modernist complex that was, in many respects, ahead of its time.
After more than fifty years of use, however, the building has become worn and no longer meets today’s energy standards. The façades and roof suffer from poor sealing, while thermal insulation is minimal. The renovation thus provides an opportunity to bring the building up to current standards while also realizing some of Karel Prager’s unfulfilled visions, including opening up the terrace on the roof of the base.
At the same time, the reconstruction places great emphasis on a detailed understanding of the original system, its preservation, and sensitive additions where necessary for safety and long-term sustainability. The goal is to preserve as many authentic elements as possible, reduce energy consumption, and open the complex even further to the public.
about the project
Architects from the IXA studio have developed an overall spatial concept that builds upon the original principles of Prager’s design. For the first time in more than fifty years, the lightweight exterior envelope will be completely replaced with a faithful replica of the original, and the building’s systems—particularly heating, cooling, and ventilation—will be updated. The steel structure will also undergo significant reinforcement.
Ceramic and stone cladding, stone floors, glass façades, anodised profiles, veneered wooden doors, window sills, handrails and other staircase elements will, wherever possible, be refurbished, restored or replaced with high-quality replicas. The aim is not to create a striking contrast between old and new, but to build on the original architectural expression while preserving the continuity, material quality and generosity of the complex as a whole.
Unlike today, visitors will be able to use the entire ground floor, where the Center for Architecture and Metropolitan Planning (CAMP) will return after the reconstruction. The base of the cubes will once again serve as a space for gatherings, exhibitions, lectures, and discussions, as well as a venue for educational programs for children and the public—just as it was intended from the very beginning. The atrium will become a central connecting space from which visitors will be able to access all parts of the center. A new feature will be access to the roof of the base, where an observation deck with a bistro will be created.
The administrative areas on the upper floors will also be arranged more practically. Modular partitions, suspended ceilings, lighting, window sills and furniture will follow the building’s original order while creating a contemporary working environment for an institution concerned with the future of the city. It is on these floors in particular that Prager and Kadeřábek’s system demonstrates that it is not merely of historical value, but remains a viable framework for working with the city in the twenty-first century.
The surrounding grounds are set to be transformed into a public park with new areas for people to spend time in, with the landscape design being developed by the Land05 studio. At the same time, pedestrian connections between Vyšehradská and Na Moráni streets and the neighborhood surrounding the Emmauss Monastery are to be strengthened.
a circular approach
One of the fundamental principles of the reconstruction is to make maximum use of existing structures and materials. It all starts with the interior furnishings, which will be moved to the IPR Prague’s temporary premises in Holešovice or repurposed. Next, the removal of non-load-bearing structures will begin. Plasterboard and masonry partitions will be dismantled gradually so that metal, gypsum, and mineral components can be effectively reused. Next will be the dismantling of the building envelope. When dismantling the facade elements, the glass panes will first be separated from the aluminum frames. The material will then be sorted into ferrous and non-ferrous metals.
The next stage involves removing the roof cladding, during which thermal insulation and bituminous membranes will be sorted. This will prepare the building for the next phase of work on the steel support structure. The dismantling of the load-bearing structure will proceed from the top floors downward—from the perimeter to the core and symmetrically—to ensure an even load on the structure during the work.
IPR Prague is collaborating on this circular reconstruction process with Cyrkl, a company that already has prior experience with similar projects. However, this is the first project of its kind in the Czech Republic to be commissioned by a public authority.
The work will proceed in accordance with a pre-renovation audit prepared by experts from the Czech Technical University in Prague (CTU), which maps out the possibilities for recycling and reusing building materials such as steel elements, concrete, bricks, and glass. It also specifies the quantities of each material that can be recycled and the potential savings this may generate. The materials will therefore be gradually and carefully dismantled, sorted, and prepared for reuse.
a more energy-sustainable complex
The entire complex is undergoing a fundamental transformation of its energy infrastructure. The buildings are being prepared to move away from their current energy sources and towards long-term sustainable operation.
The main pillars of the energy strategy are:
Ground-source heat pumps powered by deep geothermal boreholes
A rooftop photovoltaic power plant installed on the administrative buildings
A significant reduction in primary energy demand through a combination of modern technologies and improvements to the building envelope
Rainwater management and reuse across the site
history of the complex
The Association of Design Studios (Sdružení projektových ateliérů) is established, including Karel Prager's GAMA studio. The organisation is initially planned to be located near Hlávka Bridge, but following revisions to the design of the North–South Highway, the project is relocated to the area next to the Emmaus Monastery.
Construction begins based on a design by Karel Prager and Jiří Kadeřábek. Prager develops his vision of a "vertical city", resulting in three floating glass-clad pavilions, standing on a steel base structure with circulation cores.
The complex is completed on a smaller scale. Instead of the planned five buildings, only three are constructed. Today, they are known as “Prager’s Cubes”. Due to political changes, the complex becomes the headquarters of the Prague City Construction Project Institute (Projektový ústav Výstavby hl. m. Prahy), which now also includes Karel Prager’s GAMA studio.
The building undergoes its first partial renovation. The windows and doors are refurbished, and an additional façade layer of black glass is added.
The Prague City Development Authority (Útvar rozvoje hl. m. Prahy) moves into the complex. Six years later, the organisation becomes the Prague Institute of Planning and Development (IPR Prague).
The Center for Architecture and Metropolitan Planning (CAMP), designed by the architectural studio NOT BAD, opens on the building's ground floor. The exhibition spaces occupy the location originally intended by Karel Prager for the Baucentrum, where the studios within the association and collaborating artists were to present their work.
The metal fence on the sculpture of Miloslav Chlupáč, which separates the complex from Vyšehradská Street, is removed. The complex thus opens up even more to the public.
The Prague City Council approves an extensive reconstruction of the entire complex.
Construction work begins.
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