Bethesda Medical Center

In 2019, August Green began to collaborate with the Bethesda Medical Center in Cap Haitian, Haiti. During this project, we became troubled once we realized that designing a single hospital would not solve the complex challenges we observed in Haiti. As a result, we have concluded that we need to think differently about how the impact from a single project could create subsequent implications not just for the users but also for an entire community as the origin of a ripple effect.

While the task may have felt overwhelming, we desire to challenge the status quo and create localized community empowerment strategies. We cannot talk about equity or justice in our work until we have engaged, experienced, and empathized with those we are building for. I've come to realize that the most significant challenges go beyond the act of design itself.

Bethesda started as a ministry of One Mission Society in 1961 when nurse, Flo Boyer, saw the suffering of many Haitian people and the lack of healthcare available. Since then, Bethesda has grown, and we are now working towards a new purpose-built medical center to meet the growing need. Flo Boyer began to treat patients in a 12x12 building until the first campus buildings were completed in 1965 and 1968.

Since the completion of the original campus, Bethesda Medical Center has served the community well. However, after many years, the medical center program has outgrown its spaces and has started to deteriorate. In response to the need for new facilities, Bethesda Medical Center purchased new land for development on the city's outer edge and engaged with August Green to design the new campus. The campus' new location can serve both the city center and the rural areas outside the city. In addition, since most of the patients will be traveling on foot to get to the medical center, the design team created a campus plan to provide families with safety, food, and shelter while waiting for other family members to complete medical services and treatments.

After completing our site and environmental research, we realized that we could harness the northeast prevailing winds for natural ventilation. The design team used CFD (computational fluid dynamics modeling) to study wind flow on-site and through building formations. The design team wanted to harness the flow of wind on-site; therefore, the campus layout and planning is designed as a series of courtyard buildings surrounded by high and low planting layers that provide shade and cooling. Our strategy is to use planting to provide shade to the structures and pathways while letting the evapotranspiration of the gardens and the thermal mass of the earth cool the air. In addition, these layers of vegetation collect particulates from trash burning and dust as they pass through the thick layers of planting.

From the outset, we sought to create a truly sustainable campus entirely off-grid. The project is designed to function on solar energy, aside from a backup emergency generator, providing power to the X-ray facility. All waste and water are treated on-site, utilizing the treated black and gray water for landscaping. Multiple bioswales are incorporated throughout the site to manage stormwater and increase planting. A public well is planned to provide fresh water to the community, with charging stations provided for people to charge their battery-powered light bulbs for use at home later.

The program of the Bethesda Medical Center is vast and comprehensive, including HIV Treatment Center, TB Treatment Center, Dental Clinic, Women's Health and Maternity, Pediatrics, Surgery Center, General Practice, Laboratory, Physiotherapy, Radiology, Urgent Care Unit, Back of House Functions. Additionally, the pharmacy, kitchen/canteen, administration, registration, security, and the doctor's residence are located on the north and south sides of the site. The design team went through several programming rounds with the client team and medical staff to ensure that adjacencies and shared functions were laid out properly across the site.

Throughout the project, we continued to study how wind flow would interact with the building shape, opacities, and courtyards. We wanted to provide adequate natural ventilation to all spaces; therefore, CFD modeling was used to track the effectiveness of the design and move from theory into practice.

The interior and exterior spaces utilize open vented blocks with high ceilings to allow fresh air to flow in while hot air rises and is drawn out through chimneys. The CFD modeling diagrams show the difference between September months with the highest wind velocities and March with the lowest wind velocities. When looking at the chimney stack in both images, the airflow velocity remains unchanged while the velocity of cross ventilation varies.

As described in an early concept sketch, the design team wanted to bring light and air into the interior spaces. Since only the Lab, X-Ray, and Pharmacy would receive Air Conditioning, all other areas would be naturally ventilated. Though the building and site layout took advantage of prevailing winds for natural cross-ventilation, we wanted to consider a roof system that could generate air flow with or without cross ventilation.

To achieve this, the roof is lined with skylights and whirlybirds placed on a small chimney. While there are many methods to accomplish the stack effect we were looking for, prefabricated skylights and whirlybirds are the most suitable methods for adhering to local sourcing requirements and construction capabilities. When combined with the double layer roof system, the CFD modeling shows the airflow within the space as a vortex at the upper region. The combined effect of cross ventilation with solar-activated chimneys allows fresh air to move rapidly and continuously through the spaces. Below the skylights is a translucent polycarbonate panel. This panel is hung to reflect and diffuse daylight in the space, allowing it to bounce between the abled curves of the ceiling and illuminate the space. The shape of the interior ceiling is designed to reflect light, which allows for hot air to rise and be carried out through the chimney or the roof plenum while reducing the amount of energy needed to power lighting systems throughout the day.

A major challenge is building construction methods and materials. The site is mostly clay sitting only two meters above the water table and situated in earthquake and hurricane zones. These challenges led the design team toward a design for single-story buildings with broad footprints. In conversation with the EMI Engineers who consulted on the project, the team decided to avoid concrete slabs overhead while reinforcing the inside of the earth block wall with a basketweave system of rebar. Additionally, the building materials are resourced from the local community to help foster the local economy. Simple steel trusses are designed to be lightweight for hand lifting, uniform, and hand-welded on site. The earth blocks used for the walls have been designed to be compressed on-site using earth from the site, with little additional clay or sand being brought to the site.

Service Yard

Director’s Residence

Bethesda Medical Center

Dr. Rodney - BMC Director

Bethesda Board of Directors