As of midsummer, 2016 was on track to be the hottest year on record worldwide. As global temperatures rise, the passive and active design strategies used in the hottest parts of the world to keep buildings habitable, reduce the money spent on air conditioning, and conserve water resources become relevant in more regions than ever.
The following ten projects—all completed over the past five years—represent a variety of approaches to blocking the heat, including concrete domes modeled on palm trees, building forms borrowed from Arabian tents and Arizona canyons, motorized louvers controlled by sensors, solar chimneys tucked behind recycled copper panels, and a veil of twisted white fabric sunshades.
1. Cayan Tower, Dubai, United Arab Emirates
Each of the 75 floors of Cayan Tower is slightly rotated on the building’s axis in comparison to the floor below, resulting in a structure that twists a full 90 degrees from base to top. The twist allows the ground-floor retail colonnade to face the Dubai Marina’s waterfront promenade, while the residential floors above have optimal views to the Persian Gulf. The helical form also provides self-shading for the tower and helps shield the building from northern winds and the sand and dust they often carry.
Exterior terraces, metal cladding panels, high-performance glass, and deeply recessed windows further shield the interiors from the hot sun while still letting in daylight. A nighttime air–flushing system passively cools the tower’s exposed slabs after the sun goes down. Designed by the Chicago office of Skidmore, Owings & Merrill for the Dubai office of Cayan Group, the tower contains 495 condominium units that range from studios to four-bedroom duplexes. The local office of Khatib & Alami served as the architect of record. The tower was completed in 2013.
2. Hamad Bin Khalifa University Residence Halls, Doha, Qatar
Temperatures in Doha rise above 100 degrees Fahrenheit (38°C) for much of the year, and dust storms are common. In creating housing for 1,200 students, Hamad Bin Khalifa University needed to protect residents from the elements and encourage a sense of community. Treanor Architects of Lawrence, Kansas, and Burns & McDonnell of Kansas City, Missouri, teamed up to create two villages modeled on traditional Islamic towns. Each village consists of five residential buildings and one community center organized around traditional courtyards.
Thick walls provide insulation against extreme desert temperatures. Stainless-steel screens and deep-set windows let in natural light while mitigating solar heat gain. Graywater and stormwater are captured and reused for irrigation, water features, and toilet flushing. Wind turbines at the main entrance generate energy, as do the photovoltaic panels that top all roofs and shade the parking lot. Sustainability monitors display real-time data about each unit’s water and energy use and give students guidance about how to live more sustainably. The complex opened in 2013.
3. John M. Roll United States Courthouse, Yuma, Arizona
Creating visual transparency between the outside and inside was of paramount importance in the design of the John M. Roll United States Courthouse, given its public nature. However, the interior had to be protected from solar heat gain, since temperatures in Yuma can rise as high as 120 degrees (49°C). Ehrlich Yanai Rhee Chaney Architects of Culver City, California, with Phoenix-based Sundt Construction as design/build partner, addressed both considerations by equipping the south-facing main facade with a double-height glass curtain wall shielded by a large canopy propped up on steel columns. The resulting shaded “front porch” supports photovoltaic panels generating 20 percent of the building’s electrical needs.
Sandstone and brick provide thermal mass. Trellises supporting climbing vines protect the recessed windows on the eastern and western facades. Although Yuma typically experiences only three inches (8 cm) of rain each year, flash floods are not uncommon. An arroyo constructed at the entrance channels stormwater into retention basins to allow it to percolate into the ground. Built for the U.S. General Services Administration, the courthouse opened in 2013.
4. King Abdullah Petroleum Studies and Research Center Residential Community, Riyadh, Saudi Arabia
Even oil-rich countries like Saudi Arabia recognize the need to accelerate research into alternative-energy technologies. To do so, the government has created the King Abdullah Petroleum Studies and Research Center. The research and office center itself, designed by London-based Zaha Hadid Architects, is scheduled to be completed in October 2016. To attract and retain an international staff, the Dubai office of HOK designed a housing complex for 1,900 residents, which opened in 2013. The core includes three apartment buildings, shops, a library, a dining hall, recreation facilities, a mosque, and a supermarket, surrounded by 200 single-family homes. Residences are placed close to each other to create shaded pedestrian alleys.
The design team turned a dry riverbed into a linear park that channels stormwater. All wastewater produced on site is reclaimed to irrigate the site’s desert-tolerant landscaping. Homes rely on a concrete structure for thermal mass and have exterior shading and rooftop solar thermal hot-water panels. To power the complex, HOK designed an adjacent solar energy field, billed as the largest in Saudi Arabia.
5. King Fahad National Library, Riyadh, Saudi Arabia
For the expansion of the country’s national library, originally built during the 1980s, the government of Saudi Arabia held an international competition and selected Gerber Architekten of Dortmund, Germany. The designers enclosed the existing cross-shaped building inside a new, square building clad in a transparent facade of polytetrafluoroethylene and surrounded by 1,000 twisted pieces of white fabric held in suspension by steel cables. Optimally positioned for sun shielding, the panels reinterpret the structure of traditional Arabian tents and allow occupants to see out to the new adjacent plaza. Gerber also reoriented the building’s main entrance so that it faces the plaza.
The roof of the old library building now serves as a reading level, lit by the new building’s skylights, with the stacks tucked in the old library below. The existing concrete dome was reconstructed with steel and glass, enabling it to bring in daylight while remaining a visual landmark in the city. The new facility was completed in 2013.
6. Mariposa Land Port of Entry Expansion and Modernization, Nogales, Arizona
Built during the 1970s, the Mariposa Land Port of Entry was ill-equipped for post-9/11 security requirements and 21st-century traffic volumes. Drivers of commercial trucks, cars, and other vehicles often waited many hours in hot conditions—local average high temperatures in June are 96 degrees Fahrenheit (36°C). To modernize and expand one of the busiest land ports of entry into the United States, the General Services Administration brought in Phoenix-based Jones Studio. The designers streamlined passage by reorganizing the site into four linear zones: one for southbound traffic, one for northbound privately owned vehicles, one for northbound commercial traffic, and one for pedestrians.
The pedestrian spine occupies the center and consists of a desert garden landscaped to provide shade for those on foot. Pavement and roofs throughout are designed to collect rainfall and store it in underground tanks for use in irrigating the low-water plantings. Canopies, trellises, and roof structures provide shade for travelers, while the insulated concrete structure mitigates heat indoors. Completed in 2014, the facility also incorporates solar hot-water heating, daylighting, and energy-efficient lighting.
7. New Mexico Highlands University Student Center, Las Vegas, New Mexico
New Mexico Highlands University’s new student center occupies a prominent intersection on the town/campus border. The design challenge was to create a building that emphasized transparency while mitigating the heat of the sun. To achieve this, Diamond Schmitt Architects of Toronto, Ontario, Canada, in a joint venture with Studio Southwest Architects of Albuquerque, New Mexico, gave the facility a glazed aluminum curtain wall shielded on three sides by a motorized louver system.
Set up two feet (0.6 m) from the facade and ten feet (3 m) above the ground, the louver system maintains transparency for passersby. Various sensors track the position of the sun and monitor temperatures and other climatic conditions in order to keep interior temperatures comfortable. A geothermal well field with two chillers serves all of the building’s heating and cooling needs. Organized around a three-story atrium, the facility includes study and meeting areas, a bookstore, a theater, student offices, a conference facility, a post office, a café, a cafeteria, and a student governance chamber. The facility opened in 2013.
8. Phoenix Biomedical Campus Health Sciences Education Building, Phoenix, Arizona
The University of Arizona College of Medicine–Phoenix partnered with Northern Arizona University to create the Phoenix Biomedical Campus in downtown Phoenix. For the Health Sciences Education Building, the design team—CO Architects of Los Angeles with the Tempe, Arizona, office of Ayers Saint Gross—took inspiration from the stratified rock formations of Arizona’s desert canyons and positioned the six-story concrete-block structure for optimal solar orientation and clad it with pleated panels made of recycled post-consumer-use copper. Behind these panels, a four-inch (10 cm) air cavity serves as a solar chimney, exhausting hot air.
Just as the region’s slot canyons shade themselves, narrow fissures in the building’s form provide self-shaded access to natural light. The two wings of the building flank a central “canyon” courtyard that exhausts air passively and is topped by a roof made of polytetrafluoroethylene fabric. By recessing the ground floor 40 feet (12 m), the designers allowed upper floors to shade the portico, which leads to the glass-enclosed main entrance. Completed in 2012, the facility includes classrooms, learning studios, laboratories, offices, study rooms, a cafeteria, and conference rooms.
9. Queen Alia International Airport, Amman, Jordan
To handle increasing passenger traffic, the government of Jordan commissioned a new airport that could accommodate up to 12 million passengers annually by 2030. In order to moderate the temperature extremes of Amman’s semiarid climate, London-based Foster + Partners, working with a joint venture of local architecture firms Maisam and Dar Al-Omran, chose concrete for the structure because of its high thermal mass.
The roof consists of shallow concrete domes shaped to resemble palm-tree canopies and supported by trunk-like columns. Skylights between the “leaves” let in daylight; patterns drawn from traditional Islamic forms are etched into the leaves’ undersides. Above each dome, insulation and an aluminum shade mitigate solar heat gain, and a small air gap between the aluminum and the dome allows air to flow freely for further cooling. The domes are modular to facilitate future expansion. The roof extends beyond the perimeter of the glass curtain wall to provide shade in tandem with horizontal louvers. The first phase opened in 2014.
10. South Australian Health and Medical Research Institute, Adelaide, Australia
To showcase the state’s medical research industry, the government of South Australia commissioned a flagship facility in a parkland setting in Adelaide. The challenge was to expose the activity within and give researchers ample views to the outside while blocking the sun’s heat. The Adelaide, Melbourne, and New York City offices of Woods Bagot collaborated on the design and worked with the local office of the engineering firm Aurecon to devise a facade that consists of 15,000 triangular glass/aluminum panels set within a hybrid steel diagrid.
The design team used parametric modeling to tailor the shape of each panel so that it provides optimal shade for each area of the building. The write-up areas and laboratories on the northern side of the structure receive the most natural light. Grouping support services along the western side allows them to shade the rest of the building from the hot afternoon sun. The first floor is recessed to shade the ground level; the air-conditioning system draws cooler air from this level to exhaust it at the top. The facility was completed in 2013.
Ron Nyren is a freelance architecture, urban design, and real estate writer based in the San Francisco Bay area.
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