How the pandemic put building design and ventilation back into the public health conversation

In recent years, people have thought of ventilation strictly in terms of keeping buildings comfortably warm or cool.

But for millennia, those systems were influenced by the need to keep our dwelling spaces healthy — often in the face of deadly diseases like cholera or yellow fever.

Sara Jensen Carr, an assistant professor of architecture at Boston's Northeastern University, says that even with the lessons history can teach us about the interplay between health and architecture, we still have a lot to learn about how to adapt — or rebuild — our homes, schools and workplaces to better protect ourselves against COVID-19.

"Many of our buildings have been so empty for the past six months, I think we're actually only beginning to find out what the issues are," Carr told Spark host Nora Young.

"I think this rupture, and this pandemic, is going to have effects far, far beyond the buildings."

Ventilation has become a major focus of public health officials and researchers, as they try to learn more about the novel coronavirus's ability to travel and infect humans via airborne droplets and aerosols.

Many schools, for example, have very few windows that can open up to let in fresh air from outside. Nor do they have enough outdoor space to facilitate outdoor lessons.

This isn't only because of concerns for efficient airflow, said Carr. She noted that there was "a line of thinking that was very prevalent in the 70s and 80s, which also thought that windows were actually distracting for children, so you shouldn't put more windows in schools."

And as companies try to adapt to a greater percentage of employees working from home, a home office will likely become more important for prospective renters and homeowners, she explained.

Carr's upcoming book The Topography of Wellness: Health and the American Urban Landscape explores how concerns about public health — and especially contagious illnesses — have shaped our public space and architecture.

In the mid-1800s and early 1900s, she explained, standing water and puddles in dirt and cobblestone roads were linked to cholera and yellow fever outbreaks. Newly built sewer systems and freshly paved roads helped move the wastewater out of the streets.

She also pointed to sanatoria for tuberculosis patients in the mid-1900s that were designed and built with wide porches so patients could sit outside to get fresh air, and tall windows to let the sun in.

Those design tenets, along with a mostly white decor that contributed to "the sort of appearance of sterility," said Carr, directly influenced the modernist architecture movement of the time.

"Although it was not based on epidemiological reasoning so much," said Carr — as sanitoria patients were primarily being treated with vaccines — "the sort of aesthetics of the vaccines and germ theory definitely trickled down to architecture."

Connection between buildings and health

Fast-forward to the 21st century, and diseases like cholera aren't typically a primary design concern. Instead, comfort, control and energy efficiency took priority.

Sealing windows shut and developing complex mechanical ventilation allowed the construction of ever-taller skyscrapers, with residents able to personally control the temperature and air flow so they can either work in their office or live comfortably in their condominium.

As a result, "we've become somewhat separated from understanding the connection between the built environment and health," said Carr.

The continuing research into COVID-19, meanwhile, suggests people are at a greater risk of contracting the virus in enclosed indoor spaces.

"I'm hoping what comes out of this is a concentration on not just bringing natural ventilation back into these buildings, but recalibrating our priorities of thermal comfort and fresh air," she said.

Homes of future past

Toronto-based architect Terrell Wong and her firm Stone's Throw Design take on small, custom jobs that often incorporate low-energy building designs and natural materials.

Simple design elements like a split-level home and having two windows or other openings in a room can help encourage natural or "passive ventilation," she says.

She's also worked with sustainable materials like clay or rammed earth (natural building materials such as compressed soil or gravel) that were more commonly used hundreds or even thousands of years ago. They have a lower carbon footprint than concrete, she said, and can even help maintain a stable level of humidity inside.

"I kind of think that it's our mindset … [that] we go to the Home Depot, and these materials are already there. We don't have other choices. But there are choices," she argued.

"Yes, some of the materials are more bespoke, because they're not so common. But … making decisions about material that may cost more upfront, but you never have to change them? That is the most green thing that you can do."

Aaswath Raman, assistant professor of materials science and engineering at University of California Los Angeles, suggested another way to control airflow and ventilation: instead of heating and cooling the air, do it to the walls.

"This is often called radiant cooling, or radiant heating," said Raman, who has been studying ways to harness the natural movement of heat to create more sustainable cooling technologies. 

"Instead of basically having to pump … warm or cold air into a space, you can kind of cool the person, or heat the person up."

Change often reactive: Wong

Wong thinks we'll see more buildings incorporate these design elements, since the pandemic has thrust ventilation and building design into the public consciousness.

But it will take a while to get there, she said, before the wider public consider a rammed earth home something other than the purview of "crunchy-granola druids on the sideline of life."

"It's typically a slow change, unfortunately…. We're usually very reactive to things as opposed to proactive."

In the meantime, what can people do right now to improve their home's ventilation?

"Well, the simplest thing, I think ... would be: change the [air] filters more often than once a lifetime," said Wong.

Written by Jonathan Ore. Produced by Olsy Sorokina and Michelle Parise.