June 16, 2011 — At a horse barn built in the 1980s by businessman and philanthropist John Kluge to house his prized thoroughbreds, University of Virginia students spent four weeks this summer focused on the small details, like the patterns of sunlight reaching the interior walls.

In the process, they grappled with some of today's biggest challenges, including how architectural design can significantly reduce the energy required by buildings.

The barn was the focus of a graduate-level architecture class, "Adaptive Reuse: Regenerative Design at Morven," in which students were tasked with studying how to convert the barn's stalls into dorm rooms.

The class was one of three intensive, four-week classes that made up the second annual Morven Summer Institute, held on the grounds of U.Va.'s Morven Farm, which wrapped up last week.

From the outside, the barn – one of three identical barns on the farm – looks relatively inconspicuous and traditional. But the barn's interior feels cathedral-esque, with a soaring vaulted ceiling, exposed beams with handsome joinery hardware, and dormer windows nearly 30 feet above the brick floor.

Building on earlier student design projects that first proposed reusing the barns for living or working spaces, the class focused on how to modify the stalls to make the space work as a dorm room for two to four students during spring, summer and fall, aware of the building's current lack of a mechanical heating or cooling system. 

The class was divided into small design teams of two or three students. The teams studied basic elements of the barn's comfort and livability, such as the quality of natural light in the stalls, which two teams focused on. Inside single stalls, one team used strings to trace the path of sunlight as it moves around throughout the day, while a second team used light meters to measure the pattern and intensity of light on every square foot of the floor. Based on those studies, the teams designed various diffusion and reflection panels to better distribute the natural light within the space.

"This type of experience – where students get hands-on with details like the light and airflow that really affect the quality of the building – is essential for architecture students," said the class's professor, Karolin Mollmann, an instructor in the Architecture School, during a recent tour of the class projects.

"Damn, it's hot in here." That was the first thought of students Meghan Maupin and Tom Gibbons on their first day in the barn, and the inspiration for their team project, as they explained.

To help make the interior cooler and more comfortable, Maupin and Gibbons sought to harness the natural relative coolness of the barn's interior concrete block walls, which they had noticed as students instinctively tended to sit or lean against the cool walls.

Due to concrete's dense thermal mass, it tends to retain temperature, including the overnight low temperature, making the concrete relatively cooler than ambient air temperature during the daytime.

Better harnessing this relative coolness requires increasing the flow of air in contact with the concrete surfaces, Gibbons explained in the team's presentation. The duo proposed creating in-wall airways, perhaps a foot wide, in combination with a peaked ceiling installed over the stall, with a central hole in the ceiling that would create a chimney "stack effect," exhausting hot air out the opening and drawing in outside air through the wall airways. To further increase the surface area of contact between the concrete and the air flowing by, the in-wall airways feature a labyrinthine shape formed by small concrete fins extending inward, forcing the air to meander through the wall. 

"I do think the idea is significant," said Gibbons, a rising second-year graduate student in architecture. "Even if it just reduces the need for HVAC, that could save significant energy."

Heated or cooled water – from a hypothetical mechanical system – could also be piped through the airways to more finely and powerfully control the temperature, suggested Bill Sherman, an architecture professor who served as a class adviser, in response to Gibbons' and Maupin's presentation.

The water could even be heated by circulating it underneath a nearby composting area, where the bacteria generate heat as a byproduct of the decomposition process, suggested Ben Cohen, a professor of science, technology and society at the School of Engineering and Applied Science, who co-taught another Morven Summer Institute course on "Interdisciplinary Food Studies: History, Politics, and Technology."

Facing the compressed schedule of the class, the team constructed a full-scale mock-up of a small section of one wall. A proper, full mockup would require further study and modeling to refine details like the airway's shape, height, and air intake and outlet, said Maupin, a rising fourth-year undergraduate in architecture. The width required for the airway could also be incorporated into a wall-mounted bank of useful features like desk space, bed space and seating, the duo suggested.

The idea of creating natural air convection currents within walls has been done for centuries in many warm climates, and is used extensively in North Africa and the Middle East, Sherman said. Large buildings in the 19th century, like early office buildings, also incorporated similar design principles to passively create cooling air currents. With the rise of mechanical air conditioning and heating systems in the 20th century, many of these practices were lost, he said, but are gaining new emphasis with today's rising concerns about energy consumption and efficiency.

"In recent decades we are looking at architecture differently," Sherman said. "We are seeing architecture as part of larger systems – cultural systems, environmental systems, energy systems – rather than seeing it as just singular, aesthetically designed composition. And that changes the way you design, changes the way you think.

"The in-wall airflow design is a product of that new approach and thinking about the energy flows in the building."