Located in the heart of the city center of Mannheim, the mixed-use project New7 demonstrates how modern infill development can be successfully integrated into the existing built environment. During the renovation of the former “Galeria Kaufhof” department store, the existing reinforced concrete structure was preserved. It was expanded with a five-story addition built using a hybrid wood construction method. Exposed wood elements, green courtyards, and green facades create sustainable space for retail, offices, and residential use.
DELTABEAM® as the Link Between the Existing Structure and the Wooden Structure
The structural challenge: The smaller column grid of the new wooden structure (5 x 5 m) did not align with the wide-span grid of the existing building (10 x 15 m). To safely support the high point loads without overloading the existing building’s foundations, KEMPEN KRAUSE engineers selected a lightweight support system consisting of approximately 90 custom-made DELTABEAM® composite beams from Peikko. In the interior bays, the beams form a perfect symbiosis with a slim wood-concrete composite floor.
The benefits for the project:
Maximum room height: As a Slim-Floor construction, DELTABEAM® enables transitions flush with the ceiling without disruptive joists. This significantly simplifies the horizontal routing of the complex piping on the first floor.
Integrated fire protection: Thanks to factory-installed fire-resistant reinforcement, the system meets the REI 90 requirement without the need for additional, expensive coatings.
Flexibility: Large web openings allow for direct routing of utility lines through the beam.
380 metric tons of CO2 saved
Through an intelligent deformation concept combined with the stiffness of the DELTABEAM® beams, elastic deformations were allowed during construction, and the columns were readjusted using a hydraulic press. This optimized structural design saved 150 metric tons of structural steel and approximately 380 metric tons of CO2 equivalents compared to solid steel beams—a milestone for the sustainability of the New7 project.
