Just as in Umberto Ecco's novel The Name of the Rose, a fortress, a castle, an enclosed structure is built to protect the books, the basic idea of the building is conceived in the same concept. In the Pilsen region, the most famous castle from the time of Charles IV is Radyně Castle, which originally also had two towers. The building of the depository has the shape of a modern castle, which emerges from the former building. It is a symbol of the site's revitalisation, when a military building for servicing tanks was transformed into a building for preserving cultural heritage. In the presented conception the modern gunports bring light into the offices and vigilantly "guard" the surroundings.

The library depository is a simple mass, volumetrically based on the spatial requirements of the client. The external appearance respects the internal space. The appearance of the building is mostly determined by the proposed suspended brown facade, which defines the volume of the new mass that grows out of the original building. The light grey plaster highlighting the contrast of old and new. The escape staircase is conceived as a technical element, both in its design and in the light grey colouring of the galvanised steel, which acquires a patina over time. The new window openings and the entrance on the north-west side are framed with dark grey steel plates. The severe industrial concept is also written into the interior, where both the materials and all the wiring, including the gaseous fire suppression system, are acknowledged.