This is the third of a four-part installment of my article on Studio TAMassociati and their Pediatric Center in Port Sudan for the new PUBLIC Journal, the first publication dedicated solely to public interest design and architecture. Read the first part on the studio here and the second part on the design of the building here.
In this post, we look at the low-cost, low-maintenance mechanical and plumbing systems designed to maximize the efficiency of the building in the harsh desert climate.
DESIGNING FOR EFFICIENCY & LONGEVITY
Because the site is in an arid climate zone where temperatures often exceed 120°F, the grassy play areas and garden surrounding the hospital are understandably out of the ordinary and require constant irrigation. The architects worked with engineers from Climosfera to devise a wastewater treatment system to irrigate the greenery surrounding the site. “That is the only green in all of Sudan because of the filtration system with wastewater,” said Pantaleo. “This has become a central part of the [greater city] area where people can meet and also because at night it’s the only place where people can get light.”
Along with extreme heat, Port Sudan’s extremely low humidity level and strong desert winds kick up exorbitant amounts of dust, creating enormous sand clouds fondly named “The Haboob.” Recognizing the limited resources and a sensitive operating budget for the hospital, the design team concentrated on the cooling, insulation and filtration systems to address these adverse environmental conditions while minimizing the building’s energy consumption and maximizing the occupants’ comfort level.
Opting first and foremost for passive techniques, the team began designing the building’s envelope. Thick masonry walls made of two brick layers set apart with an air gap accumulate heat during the day, allowing the heat to rise and be released in the evenings through the attic space created between the barrel vaulted ceiling and insulated metal roof. This alternating 12-16 hour air cycle within the wall cavity helps maintain a temperature equilibrium for the interior spaces.
The use of these massive walls alone was not sufficient to ensure comfort, so the team shielded the intermittent exterior windows and walkways with braided bamboo screens to reduce solar heat gain. Again finding inspiration from the local area, the bamboo screens pay homage to fences used in the nearby refugee camps, becoming an important feature from both a cultural and functional perspective.
With temperatures maintained by the thick masonry walls and sun shades, the team returned to a successful ventilation system previously implemented 400 miles away at the Salam Center for Cardiac Surgery in Khartoum, Sudan—the traditional Iranian stack ventilation system, “badgir”. The badgir incorporates two 26-foot outdoor chimneys that poke above the building’s rooftop, pulling fresh air from prevailing North-South winds into the basement of the building. The air then weaves through a labyrinth of walls, slowing down in speed and depositing sand and dust onto the basement floors, before entering an adiabatic humidifier for treatment. The filtered air (previously at levels of 30%+ humidity) is now at a humidity of 5-10%, a temperature reduction of 10°F below the incoming temperature, and free from airborne particulates. The air then flows up to the interior spaces through small vents in the masonry walls. Finally, as the air warms, it rises up to the ceiling and exits through shorter return ventilation chimneys.
The adiabatic ‘water cooler’ system combined with the ventilation chimneys ensures continuous outdoor air flow through the hospital–the ideal condition to prevent airborne diseases amongst the patients. Electric consumption for the air conditioning system is also at a staggering 70% reduction due to coupling with the passive systems. These simple yet innovative systems for Sudan represent new methodologies that can be easily implemented across Sub-Saharan areas.
With this modest yet powerful hospital design, Port Sudan’s Pediatric Center represents tamassociati and Emergency’s shared prioritization for well-designed, location-appropriate, and easily maintainable facilities that bring peace, harmony, and beauty to distressed communities. What’s the key to achieving this success? “One of the main things–that you can call a secret–is the participatory process that has been rooted in the way of thinking in this project,” reveals Pantaleo. “There is a community that is made with the doctor, the engineer, the architect, the site supervisor–there is a group of people that believe in going that direction. That is the way to process a project with that complexity.”
In our final installment of the “Building Dignity in War-Torn Sudan” series, we’ll reveal what lies ahead for tamassociati.
Image sources: Massimo Grimaldi for Emergency NGO and Raul Pantaleo, Studio TAMassociati