Draping a Shawl around a Crystal
Casablanca Finance City (CFC) aspires to be the Moroccan equivalent of La Défense in Paris: a business district for international firms occupying the 350-ha site of the old airport. The development authority master-planned a new community with an expansive park, middle-class housing and social amenities to complement the workspaces. A tram links the complex to the city, and there is a high-speed train to Tangier that will eventually run south to Agadir. In the competition for the first office tower, Morphosis won over OMA, Zaha Hadid Architects and Pei Cobb Freed & Partners with their design of a crystalline block that is tapered at top and bottom. A second skin of aluminum extrusions is draped like a loosely woven shawl over the block to protect the glass walls from the glare and heat of the sun, while preserving views.
“We wanted something that looked hand-made and imperfect”, says Morphosis founding partner Thom Mayne. “A contrast of rough and smooth, reflecting and absorbing light, and a tension between solid and plane, much like the relation of body and clothing in the soft architecture of Issey Miyake and Yohji Yamamoto”. Project principal Ung-Joo Scott Lee explains that the extrusions are a kit of parts in three depths, equally spaced on a diagonal axis to block the sun and are clipped to a metal frame. The geometry seems to change according to the play of light, giving the building a rich texture that evokes the moucharabieh of Morocco. Morphosis originally planned to use precast concrete units but in the end a lighter material was substituted. The space behind the screen acts as a thermal barrier, and the combination of blinds and operable windows has contributed to the building’s LEED Gold rating.
The recessed base is transparent while the angled planes of glass at the crown are reflective, opening up, like the petals of a flower, to enclose a roof garden. Most tall buildings rise from a broad base or as a straight shaft, so the tapered profile of the CFC Tower lightens its mass as it draws back from the entry plaza and dissolves into the sky. Lee describes it as “a threshold to neighboring buildings and an extension of the park on the other side of the main boulevard. Though the building remains private, we wanted to give it some porosity rather than walling it off”.
Toughness and complexity have always been the hallmarks of Morphosis’ architecture, in contrast to the sensuous curves of Zaha Hadid and the sculptural planes of Frank Gehry. For Thom Mayne, this is a much simpler project than their museums and educational buildings, or their corporate work in Asia. In essence, it is a generic office tower. But his team has transformed that prosaic program into the iconic landmark of CFC, much as Zaha Hadid Architects’ Leeza Tower is a marker for the Fengtai Financial District in Beijing (THE PLAN 119). At 121 m, it is the second tallest structure in a low-rise city, deferring to the minaret of the Hassan II Mosque, just as the firm’s unrealized Phare tower in La Défense had to stay below the height of the Eiffel Tower.
For the engineers of Bouygues Maroc, the French conglomerate that built the CFC Tower and much else in Morocco, the design presented many challenges. Six subterranean parking levels excavated from schist rock provide a solid foundation. The tower is supported by its central service core - essentially a fat column. Three splayed concrete columns descend at different angles from each corner and are plugged into sockets atop four 20-t steel plates braced by a perimeter beam.
This hybrid structure of concrete and steel transfers the load of the superstructure to the foundation. On the eve of construction, the engineers proposed that 20 cm be shaved from each floor plate so that a 28th level could be added without increasing the height of the building.
Still more did the geometries challenge the local labor force, which had little experience in constructing such a sophisticated building. But, just as China and the Gulf States have embraced audacity and learned how to realize it, the CFC Tower proved a learning experience and is sure to benefit subsequent projects in the district. And the design should raise the bar for other architects, demonstrating how modernism can incorporate lessons from the regional vernacular to accommodate extreme shifts of temperature, while conserving energy.
From the four upper floors CFC executives can survey a burgeoning community and look back over the city that was laid out as a showcase of modernism during the 44 years of the French Protectorate.