Buchner Bründler Architekten demonstrate their passion for materials, light and cubature in the conversion of a coach house in Basel. Bold interventions have made the building in Missionsstrasse habitable. The main aim was to bring daylight into the interior.
Buchner Bründler Architekten demonstrate their passion for materials, light and cubature in the conversion of a coach house in Basel. Bold interventions have made the building in Missionsstrasse habitable. The main aim was to bring daylight into the interior.
A park-like inner courtyard shielded from the street is located in the immediate vicinity of the Spalentor gate. There was once a villa on the site, which was demolished at the beginning of the 20th century in favor of the current perimeter development. The coach house belonging to the villa, built in 1880, was preserved. The original service building was separated by a massive quarry stone wall into a utility area with stables, carriage room and hayloft and a living area for the servants. The fabric of the building was not altered in the course of the conversion and was one of the challenges for the conversion of the coach house into a residential building.
Due to the double-sided firewalls, to which the coach house is connected on the south-east and south-west, its interiors receive hardly any direct daylight. Bringing light into a building means opening it up. The supporting structure of the coach house, the massive quarry stone wall and the two firewalls made this simple principle almost impossible for Buchner Bründler. A kind of “house in house” system, a new building within the old walls, offered the solution.
The upper floors, constructed in light-colored concrete made of lime cement, rest on four concrete columns. However, these do not stand in the corners of the building, but further in the middle in front of the walls. Two beams connect these pillars, forming the shape of a Latin cross. The beamed ceiling of the first floor was also upgraded to a hybrid ceiling by adding a thick layer of concrete. Component activation and grinding of the concrete created robust and attractive floors. With its striking columns and beams, the new load-bearing structure looks like an oversized table that supports the house from the inside – including the concrete chimney that hangs down from the ceiling into the living space.
To a certain extent, the cross-section of these ceilings reflects the attitude of the entire design: Use what is given, preserve it, make it visible – but also intervene radically when necessary. Buchner Bründler respond to the unfavorable lighting situation with an open spatial composition. The new load-bearing system creates a variety of situationally shaped spaces. In the two “rear corners” of the coach house, the floor slabs recede diagonally from the outer walls, creating two triangular, building-high atriums. Likewise triangular skylights illuminate the atriums from above, giving them the appearance of light channels. The solid quarry stone wall is opened up by a circular, two-storey incision, thus joining the two parts of the building into a single unit.
Buchner Bründler transferred the circular motif to the façade: a large porthole window is set into the gable façade of the residential wing. In the former stable, the existing façade openings were enlarged and new ones added. The short side of the former coach house is generously opened up by a double sliding door whose lintel with guide rail extends over the main façade into the garden area. Despite the many interventions and different shapes, the façade appears harmonious. The characteristic appearance of the historic cement stone is enhanced by the oak window frames, a harmonious combination of old and new. The roof was renovated and covered with slate again in keeping with its history.
The unexpected perspectives and surprising views created by opening up the spatial structure create a certain tension between the interior spaces. They are characterized by exposed concrete, smooth plastered surfaces, washed natural stone surfaces and fir and oak wood. On the one hand, these elements lend the old coach house a tactile and lively materiality and a pleasant spatial atmosphere, while on the other, the interplay of largely untreated materials creates a rugged charm that reflects the building’s past.
Buchner Bründler followed the character of the old coach house with their interventions and tried to preserve as much of the substance as possible and make it tangible. Despite the successful conversion, in times of housing shortage the question arises as to whether the existing building with its approximately 400 square meters of floor space could have become a home for many more people instead of a detached house. A strong argument against this was certainly the enormous reduction in living quality due to the north-facing orientation, and it was also doubtful whether the old building could have made the most of its qualities.
Conversion project in Porto: Portuguese office OODA renovated a dilapidated residential building and transformed it into a modern, yet traditional building.












