Apartment block Berlin
Energy-efficient refurbishment and extension of a residential building in Berlin
Creation of 2 maisonette flats
The residential building from 1955 was modernised as part of a comprehensive energy-efficient refurbishment and an additional storey was added. The result is 2 maisonette flats over 3 floors, basement, ground floor and upper floor. The ground floor of the ‘plinth’ was refurbished and completely rebuilt. As part of the modernisation, new internal staircases were installed over three floors, while a ring beam on the top of the wall in combination with a new beam ceiling formed the basis for the extension.
The extension was realised with serially prefabricated timber sandwich panels. These highly insulated timber construction elements include integrated roller shutters and a rear-ventilated façade construction. The ground floor was given a plaster façade, while the new storey was clad with large-format fibreboard panels.
Heat is generated by a heat pump. This is powered by the large-scale photovoltaic system on the roof, while a new underfloor heating system distributes the heat throughout the house. Rainwater utilisation was also made possible via an underground infiltration system. The old building, classified as a ‘Worth Performing Building’ in the calculations, was upgraded to the EH70 EE efficiency house standard thanks to these measures – a leap from class H to A.
bfl architects were responsible for planning, construction supervision and energy and subsidy consulting.
project data
Energy-efficient refurbishment and extension
Work phases 1-8
Arnaud Bauman
Collaboration: Gresa Calliku, Morhaf Rhibani, Alexander Rothe
Construction time: 2024-2025