The architecture of the museum’s DBM+ annex building absorbs direct references connected to mining: massive in volume and sliced through with mine-like walkways and ramps. This system of adits and galleries is what links the various expansive exhibition areas created within this cavernous space. The distinct façade, fashioned to appear like a cross-section of mine workings, communicates the function of the building and therefore of the museum itself to its urban surroundings. An intriguing interplay between interior and exterior is created.

It was designed by the architects Benthem & Crouwel, and since 2009 it has been home to the special exhibitions of the Deutsches Bergbau-Museum Bochum, while also functioning as an event space. Its clear, incisive spatial concept is reflected in its use of materials and surface finishes. The façade of the cuboid building is made from mastic asphalt, and has an almost totally black, granular rough surface. The colour of the exposed concrete surfaces of the walls of the interior spaces has been left untouched, while the tone of the orange-yellow adit passageways contrasts starkly with the building’s darkened exterior and the exposed concrete surfaces. The colour design of these areas is inspired by the hues emitted by fire and embers, thereby creating a thematic connection to the blackness, which itself symbolises the interior of the Earth.

The DBM+ has a total of three levels, two of which are used for special exhibitions. Bridges connect these two exhibition levels to the main building, so that the special exhibition harmoniously integrates into the visitor flow through the permanent exhibition area. Transitional points are established within the “Mineral resources” and “Art” tours, through which content-based affiliations are also created. On the lower level is the Barbara collection. The DBM+ is fully accessible as a single entity within itself, and as part of the entire building complex.

The unusual architecture of this annex building has earned it various awards: 2010: The “Guter Bau” prize awarded by the Bund Deutscher Architekten (Association of German Architects, or BDA) District of Bochum, Hattingen, and Witten, with the façade earning 1st Prize at the Eccola Awards; 2011: The “Guter Bau” prize awarded by the BDA (at state level), NRW, 2013: Nominated for the “große Nike” prize.