This Berlin Office Complex Is Possibly the Most Sustainable in Germany

Edge Suedkreuz Berlin, located in South Berlin, is one of Germany’s most sustainable offices. Its unique construction has gathered a slew of certifications and prizes, such as the most sustainable project in Germany by the German Sustainable Building Council and the first WELL Core Platinum certification in the country.

Totaling 10,000 square meters (345,000 square feet), it is also the largest timber hybrid property in Germany and one of the biggest in Europe, according to Buro Happold, a global practice of engineers, designers and advisers that worked with architects Tchoban Voss Architekten on the project. Timber-hybrid construction combines wood with other materials to create building components.

The project comprises two linked buildings: the Carré, a larger trapezoidal structure with a footprint of 20,067 square meters (216,000 square feet); and the smaller Solitaire, which measures 11,984 square meters (129,000 square feet). Both buildings feature canteens and restaurants dedicated solely to tenants.

Suedkreuz’s division into two buildings was a requirement imposed by the City of Berlin, which dictated that the buildings leave a gap between them to accommodate a new urban plaza with green spaces and seating. The two structures are connected via an underground garage that features charging stations for electric vehicles and bicycle parking for up to 300 bicycles.

The City of Berlin has focused on urban planning in the Berlin-Südkreuz area since the reunification of the city in 1990, according to its website. The area was formerly perceived as a neglected transit area between the districts of Schönenberg and Tempelhof. There are now many developments within Schöneberger Linse, the area between the Südkreuz train station and the Schöneberg S-Bahn station, which is being developed into a mixed-use urban district that is expected to be completed by 2025.

“Berlin began to develop big mixed-used areas on empty spaces and Suedkreuz is quite an important empty area that was developed [following] a regulated master plan,” said Sergei Tchoban, managing partner of architecture firm Tchoban Voss Architekten, which designed the property.

“We were restricted by [the master plan], and many people around us were developing [properties in the area] at the same time,” Tchoban said. “That is why it became a multi-functional area with apartments, with some ground floor public activities like restaurants, cafés and so on, and of course a very good connection to public transportation,” Tchoban said.

Tchoban Voss Architekten began developing Edge Suedkreuz Berlin with their client, Edge Technologies, in 2015. Edge Technologies is a real estate developer and redeveloper headquartered in Amsterdam that is focused on sustainable buildings outfitted with the latest technology.

Edge was interested in creating a property that focused on sustainable design, “because ecology and architecture are tied closely together, and ecological decisions [impact] architectural decisions,” Tchoban said.

Because of the environmental focus, it was critical to select the right materials for the project. “It was important to not only use materials with low carbon emissions, but to also use light materials that require less energy,” Tchoban said.

Traditional half-timbered houses in Germany were an inspiration for Tchoban, as their structures were created out of wood, then filled with plaster or brick. Edge Suedkreuz Berlin was built similarly, with other materials nestled inside of the wooden fabric, Tchoban explained. Columns and beams were made from lightweight wood, and a thin concrete plate was then added for the foundation and the basement. “We have timber on every floor as the predominant material,” Tchoban said.

Tchoban Voss Architekten chose timber and lighter materials to reduce CO2 emissions. “Reducing weight is as important as reducing CO2, because weight means more materials, which means more CO2 and more energy,” Tchoban said.

This approach required a team of professionals to realize the buildings’ design in the most sustainable manner. Tchoban Voss Architekten collaborated with Buro Happold to create an integrated concept informed by building services engineering, BIM (Building Information Modeling) management, structural engineering and sustainability consulting. The modular timber system the project employs was developed by CREE Buildings, an Austrian construction collective specializing in regenerative building solutions.

According to Tchoban, the success of Edge Suedkreuz Berlin is owed to the collaboration across numerous teams. “I will say that the biggest challenge for me was to create a project that was the result of really working together with many disciplines and specialists,” he said.

The Carré building features an impressive 26-meter (85 feet) high atrium with four tree-like structures of various sizes linked by a white wooden staircase. The ethylene tetrafluoroethylene (ETFE) foil roof is supported by a wooden truss structure, which reduces weight as well as noise. “Foil is less dense than glass, so you have a better acoustic atmosphere in the atrium,” Tchoban said.

Tchoban explained that the atrium is intended to serve as a space for informal connections. Visitors and employees use the staircase to enter and exit the building, but it also serves as a meeting space, a workspace or a place for respite. According to Tchoban, the variety of uses that people find for the atrium is what was intended for the space.

On the ground floor of the atrium, there are spaces for interaction with a variety of seating options, such as pistachio-colored circular couches. The soft furniture also helps with acoustics, according to Tchoban. “You have to understand the atrium is like a living room,” Tchoban said. “You can bring [in] furniture [or] you can take it away; it gives a feeling of being at home.”

The Carré building offers a connection to the outside through its large windows, and a link to the inside, with floor-to-ceiling windows opening onto the atrium. “You can get natural light from both sides. Also, the idea is that the light comes through the foil roof,” Tchoban said. “Employees see people moving in the atrium, they see people moving outside on the railway around the building, so they are in the middle of a very dynamic place.”

After Tchoban Voss Architekten worked on the project for about two years, Vattenfall, a clean energy company owned by the Swedish state, came onboard as a tenant. Vattenfall is now the sole tenant of the Carré building.

As for the Solitaire, environmentally focused tenants have also located in that building. They include Aromaplant, a company that specializes in the cultivation, processing and trade of herbal ingredients, and Qcells, a provider of solar solutions. “All of those businesses are ecological, so they are walking the walk,” Tchoban said.

An energy efficient building is a great way to attract tenants, according to Tchoban. Companies that are focused on sustainability are attracted to properties with high environmental standards and optimal efficiency, he said. “Big owners of buildings are likely to have these certifications, and that is why you are pressed to make them — otherwise your building is not marketplace friendly.”