Twenty huge aluminium petals fold around this 42,000-seat stadium that Populous has completed in Rio Grande do Norte, Brazil, for the FIFA World Cup 2014.
The arena's design is unique. Its facade and roof are integrated and made up of 20 petal-shaped modules, designed to be higher on one of the stadium's sides, giving the impression that the sand dunes – which are common in the region – are moving. The design also enables more ventilation and light to come into the stadium.
The petal-shaped structures of the roof are made of steel trusses, covered on the outside with aluminium tiles, with thermal and acoustic insulation. Internally, they are coated with a PVC prestressed membrane. The parts are joined by translucent polycarbonate, which allows light to come through.
The Dunas Arena's roof was also designed to capture rainwater. Gutters collect the water and take it to nine tanks below the lower stands. As a result, up to 3,000 cubic meters may be captured and reused in the lavatories and for irrigating the pitch.