Description

The Central Library at Technische Universiteit Delft (Delft Technical University) is the national library of technology and the center of technical and scientific information in the Netherlands. With its extensive physical collection and electronic information services, it serves both the university population and the commercial and industrial sectors. Designed by the Dutch firm Mecanoo, this library is noted for its iconic form – an expansive green roof pierced by a conic structure. Completed in 1998, this library represents a tour de force in sustainable practice that was much ahead of its time.

The library is sited opposite the lecture hall designed by Team X architects Van den Broek and Bakema. The Brutalist concrete auditorium wields a forceful presence, physically as a massive structure and ideologically as a benchmark in the history of architecture. This imposing context was the impetus for Mecanoo’s shift from a focus on form alone. Instead the library is presented as a landscape – an extension of the campus and a place for human interaction.

On the western edge, facing the auditorium, the library begins as a continuation of the campus lawn. It is subsequently lifted into the air as a vast and sloping expanse of green. This design strategy places the library entirely beneath a grass roof that is freely accessible for walking and lounging. The roof is supported on a system of slender columns within a huge volume enclosed by canted, glazed walls on three sides. It is pierced by a massive cone structure that extends 40 m above grade. Open at the top, this iconic form is a beacon on the campus both during the day and at night.

Accessed through a broad flight of steps in the grass, the library consists of a large reading room with administrative offices and computer rooms on the eastern and southern perimeters. The cone structure rests on splayed steel columns in the center of an irregular trapezoidal floor plan and houses the circulation desk and four levels of study spaces. The majority of the collection is stored in temperature and humidity-controlled storerooms in the basement and is retrieved upon request. 80,000 volumes of the most requested books are displayed in a four-story, suspended, steel-framed bookcase on the north perimeter, silhouetted in front of a wall painted in signature Mecanoo ultramarine. Glazing both within and encircling the cone provides light for the main library as well as the study spaces.

Concern for a clear environmental strategy is seen in the critical roles played by key components of this design. The vast grass surface with its density and mass provides thermal insulation as well as acoustic soundproofing for the interior. The rainwater held by the vegetation also contributes to natural cooling in the summer. The glazed facades consist of a system of outer glazing, a 140 mm wide air cavity and a sliding inner glass. Air is drawn through the cavity and removed at the top level. For the heating and cooling of the building itself, a cold storage system is used in which heat and cold are stored in groundwater. In this case, two tubes are placed 60 m apart in a layer of sand 45–70 m below grade. In the winter, warm groundwater is pumped through one tube to the building and, when cooled, exits through the other. In the summer, cool groundwater is used similarly for cooling.

The Central Library at TU Delft predates the dilemma of the 21st century library as it adapts to a world of technology and new media. At TU Delft, books and media are assumed and co-exist without fanfare. The design with its iconic grass roof posits with success the library as an environmentally conscious place for the meeting of people and ideas.

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Originally published in: Nolan Lushington, Wolfgang Rudorf, Liliane Wong, Libraries: A Design Manual, Birkhäuser, 2016.