A BUWOG topping out on Hildegardstraße in Berlin

A celebratory moment for a special BUWOG project: A topping out was celebrated on 13 November 2025 on Hildegardstraße in the Berlin district of Charlottenburg-Wilmersdorf, where BUWOG is building 27 apartments using the GROPYUS system.

The topping out is traditionally held to celebrate the installation of the last beam of the roof and the accident-free work of the tradespeople on the construction site. Even though flat rooftops are now commonplace in many new buildings, the topping out remains the traditional highlight on the construction site – and an opportunity for the developer to thank the tradespeople and craftspeople. Marvellous things have also been achieved on Hildegardstraße in Berlin. Here, BUWOG is building a total of 27 new apartments. This is a special project for BUWOG for a number of reasons, as it is the first time that prefabricated elements from GROPYUS are being put to use here.

Sustainable use of soil resources

This serial, modular and systemic construction method makes it possible for construction times to be significantly reduced. “This is an important advantage, particularly when existing developments, such as here in Hildegardstraße, are being redensified,” Daniel Riedl, member of the management board of Vonovia responsible among other things for BUWOG’s new construction business, points out. “Not only are we building here using an existing system, but as BUWOG we are also contributing to the further development of the system in practice and in partnership – with the common aim of reducing the costs of and speeding up construction.”

Das neue Gebäude entsteht auf einem Hof in einem Bestandsquartier. Frpher waren hier Garagen. Foto: PR — The new building is being constructed on a courtyard area in an existing development. Garages were located here previously. Photo: PR

And of making it more sustainable as well: GROPYUS elements significantly reduce the use of stone and concrete in construction. The prefabricated parts consist largely of timber – a renewable and CO2-storing sustainable building material that BUWOG has also increasingly set its sights on. At least 20 percent of the development pipeline of approximately 55,000 apartments will be built by BUWOG as timber structures in various forms.”

The elements arrive by crane

BUWOG Managing Director Eva Weiß also thanked the dedicated experts at the topping out in Berlin, emphasising: “Every construction site is different, which is why a solution-oriented approach is so important in development. Here on Hildegardstraße, the individual elements had to be hoisted over the existing buildings with a crane because the courtyard entrances were too narrow for delivery. That was genuine precision work and masterfully solved.”
And so the GROPYUS components that were delivered were hoisted into the courtyard by crane and precision-assembled there and protected from rain in a secure weather-proof tent. The 27 new apartments are distributed across six storeys and a penthouse floor. Compact floor plans, modern fixtures and fittings and efficient energy standards ensure that the building is both functional and architecturally impressive. Apartments with two to four rooms will be available here, all with balconies, terraces or rooftop terraces and in a location where residential space is in high demand. The BUWOG project is located south of Volkspark Wilmersdorf, with excellent public transport connections and within walking distance of the Bundesplatz suburban train station as well as the U9 and U3 underground lines.

Using soil resources sustainably

“Such city -centre redensification projects make an important contribution to the optimal use of land, perhaps our most important resource, and to the creation of new residential space where the existing infrastructure permits,” Daniel Riedl explains. And there are also benefits for local residents. In the course of the construction work, the residential environment will subsequently be modernised and upgraded, for example with fresh green spaces and play areas.

The successful topping out marks an important milestone, just five months since the foundation stone was laid. The prospects for completion in 2026 appear good.

Philipp Erler, co-CEO of GROPYUS, also praised the teamwork and is looking forward to further construction sites: “We already have new projects in which our innovative system is being used, such as a large BUWOG project on Schlichtallee in Berlin featuring 158 new apartments.” GROPYUS already has the capacity for plenty of new, sustainable housing for BUWOG and other clients. The annual production capacity at the smart factory in Richen is an impressive 3,500 apartments.

Many more topping-out ceremonies will therefore follow.