Roof extension Berlin-Friedrichshain

Two adjoining Berlin apartment buildings from the Wilhelminian period are each being extended by a further full storey and a converted attic storey. Eight new residential units are being created in Berlin’s urban space on an attic area of the existing buildings that has been unused up to now, in the sense of inner-city redensification.

On the side wings, two generous roof terraces were planned for the outer through-roof flats. The difference in height between the two buildings resulting from the sloping terrain is absorbed in the central flats via a so-called split level. Three steps connect the common rooms of the loft-like flats. A centrally located core area with sanitary facilities, adjoining rooms and kitchenette divides the open floor plan of the residential units.

Dormers and skylights in the attic increase the usable space and allow plenty of light to enter. The two external lifts in the inner courtyard provide access to the new floors and also have intermediate stops on the lower existing floors. This provides convenient barrier-free access for all users.

The façade of the new full storey takes up the rhythm of the existing windows with the floor-to-ceiling, so-called French windows. Based on the typical Berlin roof, a combination of pitched roof and flat pitched roof in a wooden beam construction is planned. The attic flats receive bright and light-flooded rooms through a skylight strip on the courtyard side.

In addition to the positive aspects of dust binding and improved rainwater runoff, the extensive green roof on the flat roof also provides significantly improved summer thermal insulation inside the building.

Ensuring a second escape route for all flats posed a particular challenge. Street trees and overhead tram lines prevent the fire brigade from being led to some flats.