Zero-Carbon Homes Are Changing How We Live. Here’s What Goes Into Making Them (Robb Report)
Read the original article by Robb Report here.
We speak with homeowners and architects about what it takes to bring these clean builds to life.
When Laurie Pitman bought the land where she would build her new home in Oakland, Calif., the former software engineer rejected the idea of erecting a de rigueur sprawling mansion, opting instead to go smaller—and greener. It was a decision that gave her greater peace of mind. “I [had] owned a helicopter company,” she says. “I was feeling guilty about how much fossil fuel I [burned] to carry people around.”
Pitman hired an architect and settled on a 2,200-square-foot design, then found a contractor who specializes in eco-conscious projects. The team agreed on a Forest Stewardship Council–certified wood and a type of concrete that emits less carbon for the primary materials and installed 53 solar panels on the roof for her energy source. She even insisted on placing a 16,000-gallon rainwater tank—capable of storing about eight months’ worth of water—beneath the driveway, with a filtration system in the mechanical portion of the garage. “The company representative actually showed up because he said it was the first residential installation he’d ever done. It was mainly used for these big commercial sites,” Pitman recalls. “He said, ‘I just want to see what kind of nutcase is installing one of my tanks in their house.’ ” She notes that the project was “hugely expensive” and that it took two years to complete.
But she’s not the only one reconsidering the nuts and bolts of her shiny new digs. Homeowners who once put curb appeal, grand square footage and showy kitchens and bathrooms at the top of their lists are now thinking about environmental issues that were formerly swept under the rug. “It does feel like people are more and more aware of the fragility of life,” says Alex Carter, a partner at Cundall, an engineering firm that specializes in this sort of uber-sustainable development. “People don’t feel like they’re necessarily invincible.”
Far from it. Homeowners, like everyone else, are increasingly cognizant of seemingly constant climate disasters, from wildfires to floods, and the role their lifestyles might play in the havoc. According to the United Nations Environment Programme, 38 percent of global carbon-dioxide emissions come from buildings, and 17 percent of that number from housing. New construction is a prime offender, so some architects are experimenting with gentler ways to build. Some have touted the awash-in-foliage vertical forest, which crams thousands of plants onto the balconies of residential towers, as a solution; others champion 3-D printing to cut down on carbon emissions associated with the construction phase. Both ideas generate buildings that often have a distinctive look to them: One resembles a botanical garden, the other a sleek, futuristic dwelling reminiscent of the domed huts on Luke Skywalker’s home planet Tatooine. Still other architects are making environmental impact a key factor of the equation while continuing to design in a range of styles, such as Pitman’s midcentury-modern-inspired abode. But just how widely these practices will infiltrate the industry remains an open question.
The hot new buzzword here is “zero carbon.” The concept can be broken down into two distinct concerns: embodied carbon, or the carbon emitted during the construction process (including production of the materials), and operational carbon, which is the home’s footprint while lived in. The former is decidedly more difficult to optimize. “On the embodied side, looking at all the energy that’s used to harvest, extract, manufacture, ship and install every product in the building, there’s only so much control that one organization or one team can have over that full scope,” says Shawn Hesse, the director of business development at International Living Futures Institute (ILFI), an organization that grants zero-carbon certifications to deserving projects. “We require teams document [emissions] and make intentional choices to minimize and reduce [carbon] throughout the process.”
A development that’s on the path to receiving ILFI’s stamp of approval is Zero One, a new build in Malibu that’s asking $28.5 million for the first in a series of four homes. On the face of it, the modern, 14,429-square-foot design looks similar to countless other California mansions—there’s an outdoor pool, an open floor plan and an opportunity to fling open a massive sliding glass door in almost every room for that inside-outside vibe that’s come to define the state’s architecture. Tear up the floorboards and you’ll find a different story. The developer, Crown Pointe Estates, minimized concrete usage—the material reportedly accounts for a whopping 8 percent of global CO2 emissions—by placing a layer of rubber beneath the floor instead, and much of the concrete used elsewhere is recycled. The builder also swapped out steel for local timber, which, unlike the man-made metal, naturally stores carbon, and installed solar panels on the aluminum rooftop to supply renewable energy, enabling it to be off-the-grid. “It’s difficult because if you’re going to do this, you’ll likely be the first one in your community,” says Scott Morris, the director of carbon sequestration at Crown Pointe Estates. “But it’s easy because the answers are right in front of us.” The company estimates the home’s carbon reduction is equivalent to removing 46 nonelectric cars from the road for a year.
While Zero One represents a newer take on the trend, Tom and Marti Burbeck finished their net-zero house just outside Ann Arbor, Mich., about six years ago. They found that much of what they shelled out for was invisible to the naked eye. “Part of the team was an architect who spent about a year contacting manufacturers of around 900 products—tile, plaster, screws—and getting their data sheets to see what chemicals are in there,” says Marti. “We ended up using around 500 of those products. But that’s the daunting task.” The Burbecks ended up with a 3,000-square-foot farmhouse-style home that cost about $2 million to build. “Our friends thought it was crazy,” says Tom, who recently retired from a software company that he cofounded. Their additions were valuable, of course, but they’re less obvious selling points than, say, an indoor basketball court or a car gallery.
The fact that the Burbecks’ home is smaller than most of comparable price in Michigan is intentional. Some even believe that downsizing is a necessary part of the net-zero blueprint (compactness is an element of the ILFI’s Living Building Challenge), which, naturally, isn’t an idea that jibes with the array of mega-mansions in the luxury marketplace. “We continue to be troubled by the ‘bigger is better’ atmosphere in the building industry right now,” says Tom. “Big is really overrated these days. It’s wasteful; it’s a lot of space to either heat or cool or take care of.”
That may be the general rule, but it’s not entirely impossible to create a large-yet-sustainable residence. Even the couple’s architect isn’t militant about size. “You’re going to do it, so do it right,” says Michael Klement, a principal at the local firm Architectural Resource. “Don’t feel like some square-footage police is going to sweep in and sanction you because you’re building too big.”
Same goes for aesthetics. The zero-carbon movement is not about a particular look—or lack thereof. One could conceivably apply the concept to a Hamptons shingle-style house or a Bauhaus-inspired minimalist design. Real-estate developer Matt Grocoff is working on building a net-zero community (think all solar-powered, no gas lines or combustion appliances) dubbed Veridian at County Farm, also in the college town of Ann Arbor. “This whole notion that, you know, we have to invest in bunkers for this apocalyptic future is a really dreary view,” he says. “I think it lacks imagination, frankly. It’s the future out of fear.”
Grocoff also advocates for not relegating the zero-carbon philosophy solely to new construction. There are preexisting residences all over the country that weren’t designed with the environment in mind. The embodied carbon of an older house isn’t a factor—it’s already built, after all—but retrofitting the structure to cut down on its operational carbon footprint becomes paramount. Grocoff made many eco-friendly tweaks to his family home. No small feat, as the 120-year-old, Victorian-era structure is part of a historic district in Ann Arbor, so a renovation came with its own set of stringent rules. “We couldn’t tear up the plaster walls or remove the exterior cladding; we had to keep all that,” he says. “So we didn’t have the opportunity to make a brand-new house. What we did was just replace everything with the most efficient stuff.” That “stuff” ranged from the seemingly small, including swapping out the gas cooktop in favor of induction, to more extensive reworks, such as getting rid of all combustion appliances—a tall ask that meant replacing the furnace with a geothermal heat pump. Once all the solar panels were added to the gabled roof, Grocoff became the owner of the oldest net-zero home in the United States.
Impressive, not to mention admirable, but net-zero isn’t always something that pays off in terms of resale. “It’s just a lot of paperwork that doesn’t really buy you anything,” says Pitman of her experience. “For commercial businesses, it’s completely different. There’s some value in being LEED-certified. For a homeowner, no—there’s not really anything there. And that’s a shame.”
More homeowners would perhaps pursue net-zero if it were incentivized, but for now, clean-energy mandates remain nebulous. Many countries have set goals to achieve net-zero emissions by 2050, but few governments have made concrete steps (so to speak) toward reaching that benchmark. “The problem is that [long-term net-zero goals] let political leaders off the hook in the near-term,” says Kelly Sims Gallagher, a professor of energy and environmental policy at Tufts University. “They may not then feel any political pressure or compulsion to put current legislation in place that would actually get the country on track.”
In locales that lack enforced sustainability requirements, developers often struggle to get major zero-carbon projects off the ground. In Mexico, architect Juan Carlos Prazmowski is helping create what will be a high-end net-zero community in the mountains between Mexico City and Toluca Valley, where nearly 70 percent of the land will be conserved as forest. Dubbed Reserva Santa Fe, it will house 500 families, and community centers will offer restaurants, a gym and multipurpose rooms. Like Morris, Prazmowski is working with ILFI to achieve some level of zero-carbon certification, but he’s encountered quite a few bumps in the road. “It feels a bit standardized, how everything is being built [in Mexico],” he says. “It’s a lot of steel, a lot of concrete, even though we have a lot of earthquakes here. When we’re doing our material research, not many companies are open to disclosing what they have within their materials.” Some pieces of the construction puzzle are sold locally, for instance, but were manufactured in Germany—and shipping’s massive carbon footprint is no secret.
So those who want to replace resources such as steel and concrete with wood may have to resort to boxing it up and flying it around the globe (unless there just so happens to be a responsibly managed forest nearby). “Oftentimes, companies will claim that they’re using sustainable practices just because they do one thing, but they just completely neglect a lot of other things that could be equally important,” says Mark Samsonovich, the founder of Head of Marble, which claims to be the world’s first carbon-negative furniture company and has been certified as carbon-neutral by Carbon-Neutral. “You know, chopping down wood in a sustainable forest means nothing if you’re taking that wood and shipping it to China and back. And that’s one of the most common forms of production.” More importantly, because of human encroachment, the world’s trees are a notoriously limited resource, and heavily relying on them for mass zero-carbon builds would mean even more severe deforestation, the opposite of eco-friendly. “I mean, if everybody says, ‘I want to build with wood,’ it’s just too much stress on what’s available,” says Les Norford, a professor of building technology at MIT.
The wood-for-metal solution is an example of a carbon offset. Instead of this type of material switch, some developers opt to purchase credits in exchange for proceeding with a building process that has a higher carbon price tag. That way, a home might still receive a glossy, zero-carbon certification in the end, even if its construction produced heavy emissions. (But Zero One, for example, did not need to buy any credits to reach its goal, according to Morris.) The money often goes toward reforestation efforts, such as planting trees in Colombia or other heavily deforested areas, but experts have reservations about this method. “[Credits] have been shown pretty definitively, historically, to not really return very much of what they’ve promised to do,” says John Fernandez, a professor of building technology at MIT. “The ‘net-zero’ phrase is starting to become really problematic because of that.” The primary concern is that, with little to no oversight, credits may be abused—those just-planted trees could be cut down prematurely, for instance—and, often, there’s an overall lack of transparency into what a project’s supposed “carbon offset” really means. The haziness points to a much larger problem: Unless you’re trying for an ILFI certification, there are no standardized rules regarding who can call themselves “net-zero.”
As with any feel-good buzzword, there’s potential for the term “zero carbon” to go sour fast, despite its well-meaning proponents. The word “sustainability” for instance, doesn’t pack much punch anymore, as it’s slapped on just about every Gen-Z targeted brand campaign, luxury or otherwise. Such market saturation, or greenwashing, as it’s called by activists, could just as easily happen in the sphere of zero-carbon housing. There’s already a laundry list of similar-but-different eco-conscious monikers that real-estate listings use interchangeably, such as carbon neutral, energy efficient or carbon negative. Consumers may end up conflating them. “It’s this funny space between the scientific literature, which is super jargony and very precise,” Fernandez says, “and then the marketplace, which adopts some of those terms but then replaces them very easily with others. There’s a lot of confusion.”
Yet despite this murkiness, those who live in and design zero-carbon homes remain convinced that they’re the future. “If you’re designing a custom home, that’s where the stakes really get high,” says Klement, the Burbecks’ architect. “You’ve got to be thinking about this, because otherwise you’re pouring more good money down a bad chute.”
The process can be arduous, and often the result is a home that looks just like everybody else’s anyway. Still, the UN’s 38 percent stat looms.
Having gone through the experience once, Pitman is a true believer. After living in her Oakland digs for four years, she broke even in a $2.2 million sale in 2020. Now she’s building another net-zero home in Washington State—and she has learned her lessons. “The first house was pretty damn good,” Pitman says. “I’m just doing it this time for about a quarter of the cost.”