impression of a sculpted or molded form . At the base of the free-form buildings are molded landscape berms which ground the buildings and give them a sense of weight . The berms also serve as privacy screens to the offices and help soften the street edge .
The building needed to respond to three critical and very different edge conditions . On the northern edge the building needed to integrate with a sloping street edge condition . It was important that the building responded to the street with active façades while still protecting the occupants ’ privacy . On the eastern edge the building needed to embrace a very prominent urban piazza with reflection pond . This piazza is highly visible from the main vehicular entrance to the City and is used as spill-out areas for some of the Mall ’ s restaurants as well as an area of reflection for the building ’ s occupants . Arrival to the building via this piazza is marked by a triplevolume atrium that is flooded with light and allows a visual connection into , through and between the buildings wings .
On the southern edge the building needed to deal with a rather harsh condition of structured parking for the mall . It needed to do this in such a way as to provide something visually interesting and pleasing for the mall users to look at .
From a planning point of view , the building ’ s services , ablutions and vertical circulation is centrally located around the atrium that forms the center point of a ‘ star-shaped ’ plan . From here the building branches off into effectively three wings . These wings made up the extremities of the plan but were all connected , ensuring that the building could easily house three different tenants per floor , or a single tenant .
Materials Due to weight limitations and the organic nature of the form , the façades are a unique combination of lightweight steel frame construction with expanded polystyrene ( EPS ) and composite aluminium cladding . This gave the architect the ability to curve the façades with excellent thermal insulation properties and an uncompromising ‘ liquid ’ finish .
A combination of double-glazing and singleglazing with sun-screen louvres allowed the architects to ensure optimal thermal performance in the building . At the base of the building the slick , liquid finishes of the façade are contrasted by more heavy and earthy materials of stone , timber and landscaped berms .
Challenges Because the building sat on the existing superbasement that links to the Mall of Africa , a great deal of structural innovation was required to line up with existing column grids and keep the weight of the building as low as possible with minimal compromise to the functionality of the building as
Gateway West 545