modern home in green landscape
the report

Leading architects, designers, and urban planners are devising plans to help mitigate greenhouse gas emissions. Are they our best hope for a brighter future?

Like a growing number of her peers, architect Stephanie Horowitz believes in the design community’s inherent responsibility to address climate issues. So much so that her firm works only with clients who want to build or retrofit buildings that aim for net-zero energy use.

“When we meet with potential clients, it’s a vetting process,” says Horowitz, managing director of ZeroEnergy Design in Boston. “We’re very clear that this is the way that we practice architecture—it’s not negotiable.” Sustainability-centric details such as flashing, insulation, air sealing, and decarbonization are presented on equal par with floor plans and cladding. “The way that all of these things are considered is part of the design service,” she says. “It just kind of comes with the package.”

Mette Aamodt, principal of Aamodt/Plumb Architects in Cambridge, Massachusetts, takes a similar approach. Most clients are drawn to her firm’s mission-driven work. “For others, we try to educate them and be upfront about it. Sometimes we’re going to convince people; sometimes we’re not,” she admits, “but the onus is on us to make the case.” Aamodt focuses on quality over quantity and designs built with clean, healthy materials and fair labor.

For professionals like these, business as usual is simply outdated. In the U.S. today, buildings consume 39 percent of total energy used—higher than both the transportation (29 percent) and industrial (32 percent) sectors. But what if buildings—or even entire cities—could generate more energy than they used, clean the surrounding air and water, and even sequester carbon dioxide? The idea isn’t too far-fetched.

Technology to mitigate emissions already exists, is accessible, and can even be cost-effective. And small course corrections in our approach to the built environment could make a big a difference in emissions industry-wide. (Designing for resilience—that is, creating and protecting built environments that will withstand rising seas, more frequent and severe storms, and other effects of climate change—is also paramount.) According to Paul Hawken’s 2017 book Drawdown, if just 9.7 percent of new buildings were net-zero energy by 2050, global greenhouse gas emissions would be 7.1 gigatons lower. That’s equivalent to eliminating annual emissions from all livestock worldwide. Yet the biggest barrier to building greener buildings and cities may not be cost or political will, but simply inertia.

two floor interior with visible beams

Top: A modern home by ZeroEnergy Design; Above: The interior of a barn renovated by ZeroEnergy Design.

Photo: Eric Roth

“Designing a building to code is the worst possible building you could build,” says Horowitz. “We need to do better.” Considering fuel inputs, the entire lifecycle of a building and the future of the grid are essential factors, says Horowitz, a self-proclaimed “data literacy” advocate who joined the Architecture 2030 Challenge (a group with the goal to make all buildings and major renovations carbon-neutral by 2030) as a way to stay publicly accountable for all projects in her portfolio.

It’s also worth mentioning that building smaller, more efficient spaces would go a long way toward reducing our collective carbon footprint. In the 1950s, for example, the size of the average American home was about 1,700 square feet; today, it’s closer to 2,500.

Designing for Low Carbon Impact—and Human Beings

“Decisions we make as architects and engineers impact the land we build on for the next 100 years,” says Cara Carmichael, an engineer and environmental designer at the Rocky Mountain Institute, a nonprofit organization that works to dissuade the use of fossil fuels. With the help of ZGF Architects, RMI recently built its 15,610-square-foot Innovation Center in Basalt, Colorado, to be a showcase of net-zero energy efficiency.

Atrium with stairway and green wall

The Rocky Mountain Institute in Basalt, Colorado.

Photo: Tim Griffith

By using high-end windows and insulation, an airtight envelope, passive solar design, natural and efficient artificial lighting, automation and metering, natural ventilation, and photovoltaics, the building can produce more energy than it uses in a year. In cooler months, radiant heating delivers warm air where people need it most, instead of overheating low-use spaces (like ceilings and transitional areas). The result is a building that’s 74 percent more efficient than its average counterpart.

While advanced systems react to external weather and lighting conditions, people who occupy the building retain precise control over their micro-environments. Desk, ceiling, and even in-chair fans allow for personal adjustments. And while a sophisticated louver system creates shade as necessary—eliminating the need for air conditioning—individuals can open windows when they want fresh air. Because buildings like this champion low-tech methods (tight envelopes and LED lighting, for example) rather than high-tech mechanical systems, they can often be built at or near the same cost as a traditional building.

One key to success is the early integration of cross-disciplinary teams who can accurately predict how a building will perform over its lifecycle. “It’s not just a check-the-box thing,” says Carmichael, who collaborated with architects, engineers, land planners, solar and lighting experts, and contractors to crunch numbers from the get-go. “It’s a powerful tool to shape design.”

Net Zero, Passive House, and Living Buildings

Since the 1990s, various certifications, like the U.S. Green Building Council’s Leadership in Energy and Environmental Design, have emerged for healthier buildings with lower carbon impact. Now, Net Zero, Passive House, and Living Buildings labels are also helping designers create better spaces. Though specific criteria vary, they ultimately share several common goals: The design of built environments that use less fossil fuel energy, produce less pollution, and improve the well-being of people who use them.

Built in collaboration with the Miller Hull Partnership, the Bullitt Center in Seattle, a designated Living Building, is a net-positive energy building that uses photovoltaics to generate power. There’s no cooling system—windows automatically open and close—and it even employs six stories of composting toilets. In short, it operates like a natural system—always responding to its conditions.

Designer Jason McLennan explains Living Buildings in a TEDx talk.

To reduce their impacts significantly, such buildings implement these and other tools, including ground source heat pumps, smart thermostats, green roofs, and closed-loop water systems. While some features remain expensive to install, all are easy to acquire.

Several public and multi-unit Passive House projects are also pushing the efficiency envelope. In New York, the Perch Harlem, designed by architect Chris Benedict, consumes 90 percent less energy than a standard building and 75 percent less than similar new construction. “Making these projects happen—and quickly—at scale is really exciting,” says Horowitz, who has also worked on several multi-unit spaces. Elsewhere, entire communities are working toward net-zero energy goals. In Cambridge, Massachusetts, for example, plans are underway for all new buildings to be net-zero by 2040.

Portland, Oregon, whose plan to reduce sprawl and build bike lanes has resulted in its residents driving 20 percent less than the average U.S. citizen.

Photo: David Gn Photography/Getty Images

Density, Walkable Cities, and Bicycle Infrastructure

More than ever before, designers and planners are considering the effect that density can have on reducing greenhouse gas emissions. With more than half the world’s population now living in urban areas, how we lay out communities—and how we move people and energy between them—matters.

Environmentalists and epidemiologists consistently find common ground on one particular point: Walkable cities are healthy cities, with less congestion and pollution and fewer traffic accidents. Smart, compact development allows pedestrians and cyclists to move easily between home, work, errands, and entertainment, which can reduce emissions from driving by 20 percent or more. For a community to be truly walkable, according to city planner and urban designer Jeff Speck, trips made on foot must be useful (not just for pleasure), safe, comfortable, and interesting (i.e., have cool stuff to look at and do along the way).

Biking infrastructure can accomplish the same results. In the 1970s, when most American cities were embracing urban renewal, Portland, Oregon, worked toward reducing sprawl, invested in “skinny streets” and walkability, and began a three-decade, $60 million build out of bike lanes. Today, Portlanders drive 20 percent less than the average U.S. citizen, and young, educated people are moving there in droves. In other words, smart, carbon-savvy design has made it a place that people want to be. Put a bird on that.

an aerial image of the Empire State Building.

New York’s Empire State Building recently underwent a sustainability-centric retrofit.

Photo: Getty Images/Roberto Machado Noa

Retrofitting Existing Buildings

There’s one hitch, of course. New construction can, and should, employ the multiple greening strategies mentioned above, but existing structures make up the vast majority of our building stock—and most are comparatively inefficient. The challenge here is to retrofit these buildings with new technologies to reduce impact. In the Empire State Building, for example, all heating and cooling systems were recently replaced and its 6,500 windows upgraded, leading to a 40 percent reduction in energy usage, $4.4 million in annual savings, and 7,700 tons of GHG emissions saved each year. At the Willis Tower in Chicago, a retrofit brought energy usage down by 70 percent. “Rapid” retrofitting of residential housing to get to net-zero energy—where various prefab parts are added quickly with minimal disruption to inhabitants—is also up-and-coming; already tested in the Netherlands, it may soon be embraced in the U.S.

Ultimately, though, greener design will require a paradigm shift where humans consider the built and natural environments, weather, climate, and our own activity as part of the same system—not as distinct silos. “A lot of the focus has been on energy, and I feel like we’re going to solve it very soon,” muses Mette Aamodt. “But equally important is the way we live holistically with our ecosystem.”