The challenge of exposed concrete: Elisabeth Selbert House takes shape
Berlin, / Building construction / Press Release
Inner-city construction, limited space, high-quality execution and various transitions and connections to existing buildings – the shell construction for the Elisabeth Selbert House places considerable demands on PORR's Berlin building construction team. The exclusive exposed concrete surfaces for the prestigious entrance foyer are currently being created. The topping-out ceremony will be celebrated in around six months.
The Elisabeth Selbert House, an office and administration building for the German Bundestag, is being constructed in Berlin's historic centre. PORR is acting as general contractor on behalf of the Federal Agency for Real Estate Tasks (BImA) at the corner of Unter den Linden and Schadowstraße
The Elisabeth Selbert House, an office and administration building for the German Bundestag, is currently under construction in Berlin's historic centre. The client is the Federal Agency for Real Estate Tasks (BImA). PORR is acting as general contractor for the new building on the corner of Unter den Linden and Schadowstraße, together with pde Integrale Planung for BIM coordination and PORR Spezialtiefbau for the excavation pit. The L-shaped building connects two wings via a representative entrance foyer and is directly adjacent to the listed Schadowhaus. Two existing buildings are also connected on three floors via ring closures. A particular challenge is the precise compensation of height differences of up to 1.38 metres.
Exposed concrete surfaces of the highest quality
The building also houses the rooms and exhibition spaces of the Federal Chancellor Willy Brandt Foundation, giving it a high public and representative character. PORR relied on the highest quality and comprehensive planning to ensure the flawless execution of the exposed concrete surfaces in the entrance area. The work was planned and coordinated in advance with the architect and the formwork supplier. The support formwork for the walls is prefabricated in the workshop and then delivered to the construction site ready for installation. Before construction began, the PORR team completed specific training on the requirements for exposed concrete surfaces. To ensure the best possible quality, several test walls were first constructed in the basement to test various technical solutions and optimise the results for the upper floors.
The production of exposed concrete surfaces of the highest class (SB4) presents numerous challenges. These include the exact calculation of the optimal formwork removal time, the selection of suitable vibrators for compaction, the protection of the finished surfaces from damage and the consideration of seasonal weather conditions. Titanium dioxide is added to the concrete to ensure a uniformly light appearance. The precast stairs in the building must also be of SB4 quality, which requires the utmost precision when installing them in the finished stairwells.
‘As a heavily frequented reception area, the foyer should reflect the architectural quality and material aesthetics of the new building. Our team is contributing all of its expertise to this,’ emphasises Andreas Kimling, Regional Manager of Building Construction Region East.