Winterthur: Cham Swiss plans complete conversion of "Rocket" high-rise building
CO₂-equivalent alternatives are now to be used for the project, which was one of the tallest of its kind in timber hybrid construction. Cham Swiss Properties is also planning additional apartments instead of a hotel.
According to a press release, Cham Swiss Properties has revised the plans for the "Rocket" high-rise and the three residential buildings with the project name "Tigerli" in recent months. In consultation with the city of Winterthur, the decision was made to build additional apartments instead of the planned hotel. Of these, 30% are to be in the affordable segment. Cham Swiss expects the building permit to become legally binding in the course of 2026.
Building permit with strict conditions
The Winterthur ensemble is one of the largest projects in the real estate company's development portfolio. It comprises a total of around 300 rental apartments and will dominate the Winterthur skyline with the 100-metre-high "Rocket". At the beginning of April 2025, the city issued the building permit for the construction project with some important conditions (IB reported). These related in particular to the extent of public use of the top floor and access to the areas on the first floor. "Cham Swiss Properties took the conditions imposed by the authorities as an opportunity to further improve the project," says the listed real estate company, referring to a "constructive exchange" with the city.
Instead of the planned hotel use in the high-rise building, an additional 5,000 square meters are planned for residential space. "We are planning the affordable apartments in such a way that they are suitable for young people in training or for shared apartments," says Thomas Aebischer, CEO of Cham Swiss. By dispensing with the hotel use, the space on the first floor will be upgraded. Instead of a largely automated hotel check-in, Cham Swiss is now planning publicly accessible retail and catering areas. The top floor is also to be made more attractive with a viewing room and an area for event and catering use. "A public zone in a residential building brings with it challenges in terms of privacy and security," says Thomas Aebischer. "But we are confident that we can implement a good solution so that the entire population can enjoy the view from a height of 100 meters."
No timber hybrid construction
There has also been a change in the use of materials: "Rocket" was originally planned as a timber hybrid building, similar to a building that Cham Swiss Properties completed at the beginning of 2025 on its Papieri site in Cham in the canton of Zug. "We know the advantages and disadvantages of wood very well and therefore looked closely at the question of whether the material should also be used in Winterthur," says Thomas Aebischer. "Ultimately, for risk considerations and economic reasons, we opted for a different construction method that is just as innovative and sustainable thanks to the rapid advances in construction and material technology." Cham Swiss points to CO₂-equivalent alternatives that offer advantages, particularly for high-rise buildings - in terms of cost-effectiveness, plannability and material availability. We are talking about "optimized statics, efficient use of materials and CO₂-reduced concrete". Certification in accordance with the recognized SNBS Gold standard is still planned. The "Rocket" project was previously advertised as one of the tallest timber residential buildings in planning.
Completion expected in 2030
"Once the conditions have been resolved, Cham Swiss Properties will withdraw the appeal it lodged for formal reasons," the company announced. The real estate company expects the building permit to become legally binding in the course of 2026, with construction set to begin in mid-2027. Completion of "Rocket & Tigerli" is planned for 2030. (aw)
