Delft University of Technology Library

Also known as TU Delft, Delft University is the largest and oldest Dutch public technical university. Constructed in 1960s, Delft University originally designed their intensive greenroof from 1993 - 1995, resulting in construction from 1996 - 1997. Meant for recreation over the library, in 2009 the greenroof was renovated. The 15,000 m2 library contains extensive underground book archives, reading rooms, the university publisher, offices, Tr'sor for historical books and exhibitions, study spaces, and a book binder and book shop. It won the National Steel Award 1998 and Corus Construction Award 2000. Mecanoo Architecten designed the library as a sloped plane, extending the grass from the ground to the very edge of the roof allowing people to walk to the top. The library is topped by a steel cone, giving the structure its unique, identifying shape. Enjoyed throughout the year, the greenroof is converted into a sledding hill in the winter.

"The large lawn roof is tilted up at one corner like a sheet of paper held by a single point. The hollow beneath houses the library. A cone, the symbol of technology, pierces the library and the landscape, affixing them like a pushpin. With a grass-covered roof, high-performance glazed facades and subterranean storage for heating and cooling, the building reaches high standards of sustainability. "The entrance affords a glimpse of the sunken book stacks for rare and irreplaceable books. Inside the towering suspended bookcase for the less fragile books astonishes the visitor. The deep blue background gives the wall-to-wall racks the feel of a theatre set. The columns in the central hall are not only structural but also provide lighting and heating. The sloping metal ceiling continues without interruption across all spaces above a floor the colour of Saharan sand," (Mecanoo Architect). With the 2009 roof renovation, the existing leaking single ply roofing was removed and replaced by a fully adhered two layered roofing system on a cellular glass insulation. ZinCo Elastodrain gives protection for the roofing system; the lightweight 6 inch deep substrate and lawn complete the Zinco green roof build-up.

Referência: http://www.greenroofs.com/projects/pview.php?id=534