The key concept of the design is the interplay between the building’s three floors. Kansalaistori, the public plaza in front of the building continues inside, merging with the public spaces of the ground floor. This busy, constantly updated floor with a multipurpose hall, a restaurant, a playground, exhibition space, and the National Audiovisual Institute’s cinema is suitable for quick visits and walkthroughs. The traditional serene library atmosphere can be found on the top floor - a calm area floating above the busy city center, offering unobstructed views to the surrounding cityscape.

These two floors, perfectly complementing each other, are created by the building’s arching wooden volume. The spaces inside the volume are more intimate, offering opportunities for learning-by-doing. This middle floor is an environment optimized for contemporary media and latest tools, containing workshop spaces for music and multimedia.

The wooden volume creates an entrance canopy over the plaza forming a large covered outdoor space that expands the building’s functions such as the ground level restaurant outdoors. The large public terrace on top of the canopy doubles the amount of public outdoor space available for library visitors and creates a new destination for people to meet at.

The spatial concept is executed by building the library as an inhabited, asymmetrical bridge spanning over 100 meters over the open ground floor space. The bridge structure consisting of steel trusses and beams is supported by two massive steel arches, tensioned together with a reinforced concrete tension slab. This structural solution has enabled the construction of the flexible column-free interior spaces. Secondary steel trusses support the cantilevering balcony and roof canopy asymmetrically from the arch structure, forming a unique structural design to accommodate both permanent and temporary functions for both the library and the public realm.