A white form sailing over old woods and a highway bypass, the city of Groningen's newly opened Education Executive Agency and Tax Office—known locally as the cruise ship or the lantern—is built to catch the wind. This is apt for a place that's forever looked to trade and commerce over the blustery edges of the northern Dutch flatland toward the North Sea.
Location Groningen, The Netherlands (Friesland Peninsula)
Gross area 517,098 ft floor area (48,040 m); 226,042 ft car park (21,000 m); 16,145 ft pavilion (1,500 m)
Completed March 2011
Annual purchased energy use (based on simulation) 14 kBtu/ft2 (154 MJ/m2)Annual carbon footprint (predicted) 4.5 lbs. CO2/ft2 (22 kg CO2/m2)
Program Office building (phase A); underground parking (phase B); public city garden pavilion (phase C)
TEAM & SOURCES
Concrete floors Betonson
Facade fin Sorba
Facade panels Blitta
Built for $185 million (€130 million) in four years by a broad private design and engineering consortium called Duo², the government building stands over 300 feet with 24 working floors. The Duo² collaborators feature a big team from Amsterdam—architects UNStudio; multinational engineers Arup; landscape architects Lodewijk Baljon; and general contractors Strukton. Duo²'s ambition is to create one of the most energy-efficient buildings in Europe.
The dense oak park across the street is a de facto partner in the project, bringing a hush onto the small city lane leading to the building entrance. If it feels a little ad hoc, that's because it is, explains a UNStudio senior architect. The real main entrance is not yet built—it is part of a flowing pavilion, garden, and underground parking garage plan due for construction over the next few years. The garden will stream daylight to the levels below, and the garage will have space for 675 cars and 1,500 bicycles. This is a project still in motion.
Two distinct operations are housed here: the Dutch federal tax service and the university student grant system. Security is tight in the entrance and lower sections of the building, with the lobby and public-facing help stations sealed from the escalators leading from the ground floor to the first; a broad staircase leads from there to the next level where the big call centers for tax and loan servicing are housed.
Above this, the two building cores support an upper tower shaped like a ship's smokestack for the student services, with a longer supporting prow underneath housing the tax office floors.
Complex operations are going on underneath the smooth exterior of the building's skin. To look at the inclined columns and the skeletal structure of the building is to look at a cross between an airplane wing and the giant curving ribs of a whale. Visitors and harried tax customers stream in and out of the new lobby unaware of all this, footsteps padding softly on recycled-rubber flooring.
Rising through the stories of the building, one can plainly see the forlorn beige towers a few blocks away that until earlier this year used to house these same government functions. The half-stripped towers serve as a vivid and windowless contrast between present and past. A disheveled potted plant spotted through a cracked door in one of the old structures hints at the drab institutional spirit from which the new building tries to break. "We wanted new concepts that would be environmentally sound and allow us to be more efficient by using a new system of flexible workspaces," says Hans Maat, project manager for the tax office. "But [the building] also has the benefit of boosting morale."
While there are some who would complain about a tax office spending money for showcase shelter, the energy efficiency of the building should save costs. A Dutch energy-efficiency rating has been applied to the building with respect to its methods and use of heating, cooling, lighting, warm tap water, ventilation, and pumps. The rating coefficient is based on the overall energy use of new buildings versus similar buildings of the past. The Duo² building gets a 0.74 rating against the standard 1.1 for office construction.
"This building shows how contemporary computational design can combine the complexities of the architectural ingredients needed in an office building, and then precisely control the major details of the project," says Ben van Berkel, cofounder and director of UNStudio. Van Berkel says computer-assisted design gets really interesting only when one can apply environmental principles to the building innovations possible with it.
UNStudio and engineering collaborators Arup forged one of the building's signature elements, the looping white aluminum "fins" banding each floor of the building to meet both ecological concerns and energy efficiency alike.