A recent addition to the historic centre of Oberhausen has helped to reinvigorate a neglected part of the city with the unusual addition of a rooftop greenhouse. The innovative project exemplifies what a location-based, future-oriented urban development can look like, that combines work, production and public space.
The project originated from the meeting of two mutually independent organisations. While the Oberhausen job centre were looking for a central location, the Fraunhofer Institute for Environmental, Safety and Energy Technology, based in Oberhausen, were looking for a way to implement its concepts for building-integrated horticulture. The city of Oberhausen brought the partners together. The combination gave rise to the idea for the administration building with a rooftop greenhouse, within the Altmarkt area of Oberhausen.
The project, designed by Kuehn Malvezzi Architects, in collaboration with landscape architects, atelier le balto, sought to find a balance between its competing objectives. The new building, contributes to the regeneration of the old centre of Oberhausen, which has recently been characterized by empty properties, bargain shops and amusement arcades. The tension between physicality of the brick building and lightness of the greenhouse gives the building a special quality.
A galvanized steel vertical garden connects the square with the roof garden. It hepls to create an effective urban planning element that purposefully combines the old and new landscape typologies as a public space.
A vertical garden connects the market square with the roof garden. It is an effective urban planning element that purposefully combines the old and new landscape typologies as a public space. An external galvanized steel staircase leads visitors from the tree-lined square up steps and platforms, past climbing plants and seating areas, to the roof. From the rooftop, the view opens over the historical centre of the city.
The rooftop greenhouse, which was planned in cooperation with Haas Architekten, is a research area used by the Oberhausen-based Fraunhofer Institute. It is hoped that this will help to realise its concepts in the field of building-integrated horticulture and agriculture within an office environment and thereby bring this into the urban realm.
Extensive use of galvanized steel is made to form the vertical garden and the rooftop greenhouse with the building designed with adaptability in mind for possible future developments in the city. With comparatively simple means, the office building can be transformed into inner-city living and workspace.
The rooftop greenhouse is designed as a U-shape around the inner courtyard. It is operated by the city and is accessible to the general public. Different cultivation methods are used in three climatic chambers for salads, herbs and fruit. Research is being carried out on further technical systems and synergies to optimise local food production.
Air and waste heat from the office building is directed into the greenhouse, its CO2 content can promote plant growth. The rainwater from the roof is collected in a cistern and used to water the plants. Greywater from the the building is also treated and reused as process water within the offices and for the plants in the vertical garden.
1. The new building contributes to the regeneration of the old centre of Oberhausen, aiming to integrate horticulture into the urban realm.