Lessons From Rwanda
MASS Design Group
The narrow design of the buildings and the long interior courtyard at Munini District Hospital, scheduled to open in 2018, mean fewer interior rooms, promoting natural ventilation and more exposure to natural light.
MASS Design Group
A recovery unit for new mothers provides not only abundant natural light but a window/fan/vent system that uses natural ventilation to circulate air. Low-tech UVGI lights near the ceiling vaporize airborne microorganisms.
Rwanda, once devastated by conflict, now enjoys a fast-growing population and economy. But most of the East African country’s limited healthcare infrastructure dates from the 1960s and ’70s, and in some areas there are no hospitals at all.
Since 2012, MASS Design Group and Mazzetti have been partnering to help address that need. In collaboration with the Rwandan Ministry of Health and the nonprofit Partners in Health, the firms have worked on several projects in the small nation, including a new OR and neonatal intensive care unit (NICU) for a hospital in Rwinkwavu, a new district hospital in Munini (which serves as a template for other district hospitals), and a new district hospital in Nyururgenge. The Rwinkwavu project earned MASS a SEED Award for Entrepreneurship in Sustainable Development, a program that recognizes innovative, eco-inclusive enterprises in countries with emerging economies.
Addressing the inherent challenges that accompany projects in Rwanda—including insufficient resources, budgetary constraints, and a shortage of locally available experience in maintaining Western-style mechanical systems—required project teams to shift their thinking. Architects accustomed to projects in North America had to accommodate tropical weather and conditions that make climate-controlling HVAC systems impracticable. The inconsistency of Rwanda’s power grid dictated how designers thought about everything from lighting design to backup power. And the country’s high energy costs put premiums on efficiency and conservation.
While conditions in Rwanda limited some options, in other ways the experience was liberating. Unlike North America, costs for materials in Rwanda far outweigh labor costs, and most building materials are locally sourced. For example, North American architects choose doors from a catalog and design around them. In Rwanda, craftspeople custom-make the doors on-site, giving architects more freedom to consider form and function and design accordingly. Similarly, building codes in Rwanda are nascent and basic and there are no formal design standards for healthcare facilities. (At the Ministry of Health’s request, MASS and Mazzetti are establishing those standards in their projects.) Instead of being bound by standards designed for Western hospitals that depend on complex, energy-guzzling systems, the project teams were free to pick and choose which Western-style approaches made sense for Rwanda, while also innovating their own context-appropriate solutions that were decidedly non-Western.
Finding the right solutions
Nowhere were these simplified solutions more evident than in ventilation systems. Rwinkwavu, for example, resides in one of the hottest regions in the country; the old NICU occupied an interior room with no access to fresh air, which made the room hot and infection control more difficult.
North American hospitals rely on sophisticated HVAC systems to control airflow to mitigate airborne diseases. In fact, design standards in American hospitals generally prevent windows from being opened for outside air to enter. But Western HVAC systems aren’t practical in Rwanda, so the MASS-Mazzetti team created a standard sectional design that optimizes cross-ventilation through a combination of passive and mechanical strategies. A system of windows located in high and low positions on the exterior walls facilitates natural cross breezes, while stack vents ensure airflow to interior wards. Stack vents create a chimney effect; heat from the sun forces air in the vents to rise, creating suction and causing air in the room to flow toward them. Instead of mechanically pushing air through the building, as a Western system would, this passive technology pulls air through by creating negative pressure.
The project team took a similar approach to the 300-bed hospital project in Munini (scheduled to open in 2018). The 155,000-square-foot facility was designed for its specific site, contouring around a steeply graded hill with an actively visited genocide memorial at the top. Yet its flexible plan was adaptable for other district hospitals the Ministry of Health planned to build, including one in Nyururgenge, a populous urban area with a different topography. The hilltop near Munini lent itself to several long, narrow buildings (a style once common in U.S. hospitals), maximizing opportunities for outward-facing windows that can open to access prevailing breezes. As outside air flows in, specially modified ceiling fans pull the warm air up and then distribute it to the upper edges of the room. Angled ceilings designed using computer analysis of fluid dynamics direct the air into small openings around the ceiling perimeter, where short-wavelength ultraviolet lights vaporize airborne microorganisms as the air passes out of the room, preventing infection between patients, staff, and visitors.
Besides promoting healthier airflow, the project team’s simpler approach to ventilation also helps conserve energy and reduce dependence on the power grid. Other aspects of the design combined to address these same objectives. For example, all patient- and visitor-accessible areas of the Rwinkwavu and Munini facilities rely on natural light during daylight hours. Narrow structures and an abundance of windows mean that patients are never more than a few meters from access to natural light. However, the simplicity of this solution doesn’t exclude Western technology; the project team used advanced software to assess the lighting and determine whether certain areas of the hospital required additional lighting, either natural or artificial.
Staffing and resource limitations make private patient rooms in Rwanda impractical. The necessity of large, open patient wards made passive solutions to lighting and ventilation both more appropriate and more feasible. In a reimagining of the traditional ward design, in which beds line the walls and face inward, the MASS-Mazzetti team oriented beds to face outward, providing patients with relaxing views of the green landscape.
Lessons with global applications
Though it may seem counterintuitive to many U.S.-trained architects and engineers, simpler solutions from Rwanda may offer real opportunities for leveraging “reverse innovation”—applying smart (and, presumably, lower-tech) solutions from the less developed world to our own context.
While the drivers for identifying simpler solutions in Rwanda may be different in the U.S., the applications here can be broad and financially important. For example, in Rwanda, where utility costs for electricity and water can consume half of a hospital’s operating budget, minimizing a facility’s carbon footprint is considered a necessity. The MASS-Mazzetti team relied on renewable energy sources as much as possible and designed systems to store water underground for the long dry seasons. In North America, where energy costs might run 3-4 percent, efficiency is more a bonus than an imperative. Even so, savings from simple, efficient designs can be significant over a facility’s lifecycle and are worth pursuing whether the underlying motive involves altruism, conservation, code compliance, or simply total cost.
North Americans should also recognize that, like Africans, they’re not immune to interruptions in their power grid. After Hurricane Katrina in 2005 and California’s Loma Prieta earthquake in 1989 increased awareness of facilities’ vulnerability, hospital design (especially in hurricane- and earthquake-prone areas of the U.S.) showed greater focus on reliability and redundancy. This year, two earthquakes in Mexico and three devastating hurricanes have reinforced the value of microgrids, which are likely to become a standard part of the energy supply for U.S. hospitals within the next two decades.
Microgrids involve a combination of an on-site energy source, storage capabilities, and a mechanism to connect them. With the inconsistent power grid and the country’s location in an active seismic zone, Rwandans have accumulated several decades of experience with simple microgrid systems involving solar panels and batteries. Besides providing emergency backup power, microgrids offer a sustainable and lower-cost supplement to externally generated electricity. Drawing on experiences with this technology in Rwanda, Mazzetti recently designed energy systems for a facility in Northern California that will be one of that state’s first microgrid-equipped hospitals.
A less obvious but no less important lesson involves the operability of mechanical systems. In Rwanda, the relative shortage of resources, including highly trained engineers, limits the ability to maintain complex systems. In North America, that ability is usually taken for granted, but maybe it shouldn’t be. For example, many LEED-certified facilities with complex designs operate less efficiently than seemingly inferior, 50-year-old systems because they weren’t properly commissioned and don’t operate as designed. Presented with systems that appear overly complex, engineers frequently look for workarounds and overrides, creating a solution that’s more workable for them but less efficient than it should be. For this reason, facility designers and operators should look beyond energy efficiency alone to seek the most efficient and operable design. If one system is designed to improve efficiency by 35 percent but also is much more complex, a more basic system yielding only 25 percent more efficiency could be the better long-term option.
Perhaps the biggest lesson from Rwanda for Western healthcare facilities is to simplify designs whenever possible. Don’t reflexively assume that more complexity is always better. Instead, architects and engineers should focus on what’s necessary and appropriate for the context; then they can apply a combination of mechanical and passive systems, as the teams did in Rwanda, to create facilities that not only are healthy and safe but cost-effective and sustainable.
In some cases, this might require reviewing codes and standards in North America with an eye toward energy and resource conservation. As such efforts take root, planners in this country may increasingly recognize the virtue of solutions born in Africa from necessity.
Arash Guity, PE, LEED AP, CEM, is associate principal and mechanical/energy engineer at Mazzetti (San Francisco). He can be reached at email@example.com. Kelly Doran, OAA, RAIC, is senior director of East Africa programs for MASS Design Group (Kigali, Rwanda). He can be reached at firstname.lastname@example.org.