Alioune Diop University Teaching Building: The Breathing Canopy, Bambey, Senegal

Bambey, located 120 km west of Dakar, sits in the Sahel region, an area defined by extreme contrasts: ten months of scorching dry heat (often reaching 45ºC) followed by torrential rains. When commissioned to build a massive new lecture facility for the local university, IDOM faced severe constraints: no sewage system, unreliable electricity, and a lack of skilled local labor.

A conventional, energy-hungry glass-and-steel university building would have been a disaster here. Instead, the architects looked at how students already behaved on campus, seeking refuge under the large branches of the few existing trees. The resulting building is essentially a manufactured forest canopy.

The Vision: The Venturi Effect on a Grand Scale

The entire project was developed from its cross-section, engineered to manipulate airflow. The Double Roof: The building is covered by a massive double roof. The top layer is a metal sandwich panel with insulation, and the bottom is a dropped ceiling. The space between them acts like the layers of tree branches, allowing air to flow through and carry heat away. The Grand Canopy: This roof extends outwards into a spectacular 10-meter overhang. This creates a vast, shaded exterior "plaza" where students can gather, study, and socialize out of the punishing sun.

Tectonics: The Triangular Lattice

The south-facing facade had to block the sun while allowing the building to breathe. The Perforated Skin: IDOM designed a massive latticework wall set three meters away from the actual classrooms. This outer skin blocks direct solar radiation but is entirely permeable to air.

The Chimney Engine: The heat trapped between this outer lattice and the inner wall rises and flows under the inclined double roof, creating a "Venturi effect." This constant flow of air acts as an engine, pulling heat up and out of the building. This passive bioclimatic strategy successfully reduces the interior temperature by a staggering 10 degrees Celsius without using any electricity. The Green Buffer: In the 3-meter cavity between the two skins, citronella grass is planted. This freshens the incoming air and acts as a natural deterrent against malaria-bearing mosquitoes.

The Living Building: Social and Ecological Independence

The building doesn't just respond to the climate; it responds to the community. Hand-Made Scale: To ensure the project benefited the local economy, the architects designed the intricate triangular facade blocks to be manufactured on-site. Using simple stainless steel molds, an unskilled local workforce of over a hundred people manually cast and air-dried 20,000 concrete blocks over six months. Water Autonomy: Addressing the lack of a sewage network, the project incorporates natural infiltration rafts with native vegetation to collect rainwater. Wastewater is purified using an activated sludge system and then discharged into these same rafts, creating a self-sustaining micro-wetland that requires no maintenance.

Data Sheet

Project: Lecture Building at the Alioune Diop University

Location: Bambey, Senegal

Architect: IDOM

Completion Year: 2017

Area: 7,533 m² (Built-up: 4,200 m²)

Key Materials: Hand-cast Concrete Blocks, Metal Sandwich Panels

Typology: Higher Education

Climate Strategy: Venturi Effect, Double Skin, Double Roof

Photographs: Francesco Pinton