Along the perimeter of the new Queen Alia International Airport building, precast concrete shade structures catch the light. The team chose concrete because “in summer there is a marked difference in climate between day and night in Amman, so the solid structure helps to regulate the interior temperature naturally,” says Foster Partners partner Jonathan Parr.
An elevated roadway fronts the airport’s three-story, 85-foot-high façade, with passenger pick up on the lower level and drop off on the upper. The vaulted ceiling of the departures hall is clearly visible through the glazing that encloses the structure.
The cranked 45-degree grid, comprising more than 80 precast concrete vaults, forms the roof plane and becomes plainly evident when seen from above, as pictured. “Our original modular concept meant that the building could be easily reconfigured, and can be again in the future, if required,” Parr says. An additional 172,000 square feet is planned for completion by 2020.
Deep overhangs of the vaulted, concrete roof structure shade the glazed curtainwall that wraps the passenger drop-off and pick-up areas. This shading, combined with the thermal mass of the concrete structure, radically reduces energy loads for the building. “The precast concrete roof shells sit on precast X-beams and column heads, which rest on in-situ concrete columns,” Parr explains.
The interiors are airy, with daylight spilling through the glazed perimeter walls and through louvered skylights in the vaulted ceiling. “We illuminated the interior with indirect sunlight by filtering daylight through split beams at the junctions between the concrete domes—the effect is a little like a desert palm, whose leaves extend and widen from very slender branches close to the trunk,” Parr says. The underside of each shallow dome is inscribed with a linear pattern that recalls the fronds of palm leaves, as well as examples from Islamic art.
At the departure gates, fixed, arced louvers in front of the glass help to further shade the building. For additional energy offset, the air is preconditioned by plants and trees in open courtyards before it is diverted into the handling systems. “The airport’s open-air courtyards also incorporate pools, which are lined with dark tiles so that they are highly reflective—they ‘bounce’ indirect daylight back into the baggage claim areas,” Parr says.
The double-height baggage claim area, which features six carousels, is located on the ground floor. The space serves the airport’s current 3 million passengers annually, but it can accommodate the planned six-percent growth per year that will result in a capacity of 12.8 million passengers by 2030.
To combat the intense heat of the Jordanian summers, the architects capped the exterior surface of the precast concrete domes with a metal cladding that serves as a heat shield. “The metal standing-seam roof is raised above the concrete domes to form a cavity for air to vent any possible buildup of heat,” Parr explains.
The raw interior surfaces of the concrete domes are left exposed, and the center of each is inscribed with a linear pattern. That pattern is echoed in the frit of the glass in each skylight. “We used body-tinted glass to carefully control the amount of light transmitted,” Parr says, and “a linear frit on the glass creates a play of light and shade internally, while combating glare.”