In its peacefulness and civility, it may have been the most Swiss protest ever. At a classical music concert in the picturesque city of Lucerne in September, two climate activists glued themselves to the stage. The orchestra’s performance wheezed to a halt, much to the audience’s chagrin.

After a brief negotiation, conductor Vladimir Jurowski announced a truce: The young protestors would be allowed to make their case, everyone in the audience would listen, and the concert would continue. What the protesters demanded wasn’t an end to oil exploration, or that everyone stop flying or driving, or that the old guard step down for having let the planet burn. Instead, they called for something else entirely: that all Swiss homes be renovated by 2030 so they could stay cool in summer, and warm in winter—but while using much less energy.

The Lucerne saga was over after four minutes. But the Renovate Switzerland movement has engineered dozens of similar protests in the country since 2022, some of them much more disruptive—including a blocking of the main Geneva lake bridge by protestors similarly glued to the surface, and protestors “slow-walking” traffic by marching down the middle of busy city streets. What the actions have in common is an urgent plea for a less carbon-dioxide-heavy “built environment.”

It’s a demand that makes sense. For all the attention given to cars, trucks, and airplanes, it turns out that houses and buildings actually make up the world’s single largest source of CO2 emissions, at a staggering 39%. The production of cement alone—omnipresent in our buildings, bridges, and sidewalks—is responsible for almost a quarter of those emissions. That’s due to the chemical processes and intense heat required to manufacture it, most of which typically involve fossil fuels.

Ultimately, any call for a greener built environment is a call for greener cement and concrete, produced less resource-intensively and designed to fit in energy-efficient buildings. A serious effort to use more eco-friendly cement would create construction jobs, slash residents’ energy bills, and get just about every country and institution much closer to its zero-emissions goals.

It sounds like a win-win, really. So why isn’t green cement the global norm in construction?

A few miles northeast of Lucerne, one Fortune 500 Europe company is trying to make it so. Holcim, based in Zug, is the world’s largest cement company outside of China, with a production capacity of 260 million metric tons per year. It has been a global giant for decades—it brought in more than $30 billion in revenue in its last fiscal year—and that means that it has been responsible for a large share of its industry’s historical carbon footprint. But Holcim is now trying to be part of the solution, developing low-emissions cement and concrete while creating materials for energy-neutral buildings.

If Holcim’s eco strategy succeeds, it could secure the company’s continued dominance in its industry and make it a lighthouse for other European and global companies to follow. Over the last decade, it has shown remarkable progress. The question is whether it can keep progressing quickly enough to meaningfully protect the planet—and to exorcise the demons of its own past.

A new challenge for ‘the waste guy’

Clemens Woegerbauer, a director of Holcim’s Swiss subsidiary, first started thinking about low-carbon cement some 10 years ago, when a request from Zurich-based construction company Eberhardt landed on his desk. The question was as simple as it was intractable: Could Holcim help Eberhardt get rid of its construction demolition waste, and perhaps recycle it into new cement and concrete?

Getting rid of construction and demolition debris was familiar work for Woegerbauer; in fact, he was known internally at Holcim as “the waste guy.” But the idea of reusing the waste was a new one—and it arrived, in a sense, at just the right time and just the right place.

A similar approach had been used by Europeans since at least Roman times, with bricks and stones from older buildings reused to construct new ones. (My own family in Belgium used to own property on which the remains of an eighth-century church were found, built with recycled stones from an ancient Roman villa. The “recycled” church stood for almost a thousand years.) But by the end of the 20th century, building codes all but prohibited the reuse or recycling of demolition waste all over Europe and the world—including in the United States, Holcim’s largest market and the source of over $10 billion of its yearly revenues. There was good reason to be cautious: Some low-quality construction materials used between the 1950s and 1990s, for example, turned out to have a life span of just 30 years, leading to a ban on their use. But even the recycling of stronger concrete, several researchers believed until recently, yielded material that lacked the strength of its “virgin” equivalent, making it a hazardous tool.

By the time Woegerbauer started grappling with the issue, however, the mindset around recycled materials was starting to change—in landlocked Switzerland in particular. The Alpine country’s population largely lives on a sliver of land dubbed the “middle country,” sandwiched between the Alps and the Jura mountains. Switzerland’s cities, lakes, agriculture, and industry all have to share this plateau; the last thing anyone needed was for this precious land to be used for construction waste sites. As a result, by the 2000s, the practice of recycling of construction and demolition debris was well established in Switzerland, and Swiss regulators were amenable to expanding that practice.

Woegerbauer and his team had their own reasons to fulfill Eberhardt’s wishes. First, recycled cement could be a new source of income. Eberhardt had to pay to get rid of its waste anyway, so it would gladly pay Holcim to do the same. If Holcim could incorporate the waste into new products, it would win twice: once when it received Eberhardt’s waste, and again when it sold its recycled cement products.

Just as important was how recycled cement would fit into Holcim’s future business model. If Woegerbauer’s Swiss team could square the circle of construction demolition material recycling, the company might go from villain to hero on CO2 emissions.

‘Decarbonizing building’ vs. selling cement

Holcim was undergoing changes at the top too. In 2017, the company appointed Jan Jenisch, the head of Swiss chemical company Sika, as its new CEO. As an outsider, Jenisch realized that Holcim needed to adapt to remain relevant in the 21st century.

Ever since its founding in the petite Swiss town of Holderberg in 1912—Holcim is short for Holderberg Ciment—the company had been expanding through mergers and volume plays. Cement is a commodity, and for a long time the company’s philosophy was that bigger was better and biggest was best. But after Holcim merged with its longtime rival, France’s Lafarge, in 2015, there were essentially no meaningful acquisition targets left. Just as important, governments and public opinion were growing increasingly vocal in their dissatisfaction with the huge amounts of CO2 the cement industry emitted each year. For Holcim’s dominance to remain the same, everything had to change.

“When I joined, I found strong, locally embedded businesses, 2,300 production sites, right-in-time supply, the largest building-material company in the world,” Jenisch told me. But what got Holcim to 2017 wouldn’t get it to 2027 or beyond, he also realized. “You have to think about how markets will develop in the future,” he said.

Those developments still included growth and new construction, he firmly believed, given the world’s growing population and urbanization. But it would have to be built on different foundations than before: those of innovation and sustainability, rather than commodities and volume. Any other approach would not have societal buy-in.

Jenisch brought on board a few newcomers to realize his mission, including Magali Anderson, a French engineer who had spent most of her career working on safety in the oil industry. Anderson joined as head of safety, but soon took on a more significant role: that of Holcim’s first-ever chief sustainability officer.

The new team soon embarked on a new strategy, culminating in the company’s signing of a “net zero” pledge in September 2020, aiming for the horizon of 2050. Instead of selling cement, Holcim reinterpreted its role in the industry as “decarbonizing building.” To an outsider, such a statement may have reeked of greenwashing—akin to a cigarette company stating it wants people to stop smoking. But each component of the new strategy came with a cold business rationale. Decarbonizing was going to either reduce costs or create extra revenues.

On a visit to one of Holcim’s cement plants, in the Swiss town of Eclépens, I saw several of the company’s decarbonizing mechanisms at work. Holcim had reduced much of its fossil fuel use there, and had created an additional revenue stream by using waste fuel instead—burning material that Holcim had been paid to dispose of. A live video feed of the kiln showed how shredded old tires and biomass were fed into the fire. The plant also rethought the composition of its concrete: Instead of using “clinker,” which is made by breaking down limestone in a highly CO2-intensive process, the company is using calcine clay and other, lower-emissions materials wherever possible.

In its construction projects, too, Holcim aimed to build better with less. Adopting practices from Roman times, it experimented with using gravitational forces or metal clamps, rather than mortar, to hold archlike structures together. In its floorings, it would use concrete only where it had structural effects, replacing it with lighter, less CO2-heavy product mixes where possible. To make up for the loss in volume of cement or concrete sold, it would come up with new applications for its products.

Finally, Holcim would take a more holistic approach to its role in the building sector. What if its concrete wall and floors could be components of buildings that could be heated and cooled in a carbon-neutral fashion? What if its concrete could fit into green urban architecture, rather than be a nemesis of it?

In its revamped global innovation hub in Lyon, France, a team of engineers came up with all kinds of innovations. On a visit late this summer, I saw what those efforts had led to, over a few short years: a superlight isolation layer for roofs, for example, that felt to the touch more like chocolate mousse than concrete and is better suited for hot climates. Or concrete walls with plant seeds mixed in, which could then turn the walls into Babylon-esque hanging gardens over time as rain poured through them.

Many of those innovations are still analogous to what concept cars are for car manufacturers: a proof of the company’s imagination and engineering prowess, but not products that have real-world impact today. Still, more of the products are crossing the barrier between theory and practice. A recently finished school in Vienna is a fitting exhibit: Finished earlier this year, the school, entirely built with state-of-the-art Holcim products, is capable of covering 90% of its energy needs through internal geothermal processes, the company claims.

In France and Kenya, meanwhile, Holcim has been experimenting with 3D printing of homes and bridges as a sustainable solution. 3D printing lets contractors and architects use concrete only where it is strictly needed; that means the structures built with it retain the same strength while using up to 50% less material, Holcim says.

A pandemic turning point

In 2020, the COVID pandemic stopped economic life throughout much of the global economy. Much of Holcim’s global leadership team wound up being stuck in Switzerland for the better part of a year.

For Clemens Woegerbauer and his local team, that proved to be a lucky break. After years of investments in product R&D, and as much time spent wooing regulatory commissions, their Susteno cement—of which 20% came from recycled demolition waste—had been making inroads on the Swiss market for two years. The lockdown gave Woegerbauer a chance to show off the product to a captive audience: his global HQ colleagues, who would otherwise have been traveling all over the world taking meetings at other Holcim subsidiaries.

Susteno was a runaway success. “I was very surprised, but it was good to see how open the group was [to our product],” Woegerbauer said. “It was the right place and the right time. Everything converged.”

Soon after, Jenisch and his executive team floored the accelerator on their global decarbonization strategy. In July 2020, Holcim launched Ecopact, a type of concrete with a reduced CO2 footprint of at least 30%, in the U.S., its largest market. In 2021 and 2022, further additions to the “eco” range of products followed, including Ecoplanet, Holcim’s green cement, and Ecocycle, a range of recycled products directly inspired by the Susteno recycling brand.

The years since have vindicated Holcim’s strategy—and the Swiss innovations that catalyzed it. Today, Ecopact and Ecoplanet are blockbusters, with each posting more than a billion dollars in global sales. The “eco” range of products helped Holcim to record revenues and profits in 2022, and by the fall of 2023, almost a fifth of Holcim’s global sales came from the eco brands. In the U.S., Amazon became a marquee Ecopact client, using the concrete for its new data warehouses in northern Virginia and giving the brand additional credibility in Holcim’s biggest market. The concrete mix used in the project there, the companies said, would reduce the CO2 footprint of the concrete by 39%.

Holcim also proved it could decouple revenue growth from greenhouse gas emissions. Its CO2 emissions per ton of cement produced dropped by 29% since the 1990s, the company calculated. The company has also diversified its product mix. Since 2020, CO2 emissions per dollar of net sales at the company have dropped by 43%—the result of a combination of higher prices, a further lowering of the CO2 intensity of its cement and concrete, and greater sales of other, less CO2-heavy building products. Holcim’s overall climate goal to be carbon-neutral by 2050 is now backed by what wonks call “science-based targets.” Practically, it means that if every company acted like Holcim, global warming would be limited to 1.5 degree Celsius between now and 2050, rather than the more than 2.5-degree pathway it is on now.

Legal and regulatory battles loom

Holcim’s recent transformation is a remarkable turnaround story. A company that just a few years ago was seen as a major villain by climate activists is now hell-bent on proving it can be a green ally. But to continue its sustainability winning streak, Holcim will have to outrun its more distant past.

In Switzerland, Holcim faces a potentially precedent-setting lawsuit from a group of Pacific Islanders. The plaintiffs hail from the Indonesian island of Pari, one of many Pacific islands drastically affected by global-warming-induced sea level rise. In a court in Zug, they are seeking damages from Holcim for the company’s role in emitting the greenhouse gas emissions they believe are responsible for their deteriorated living conditions. According to a report by the Climate Accountability Institute, commissioned by an NGO that supports the plaintiffs, Holcim and its predecessors are responsible for 0.4% of all global postwar CO2 emissions—more than 7 billion tons of the greenhouse gas. If the judge finds Holcim liable, it could open the floodgates to similar cases from affected populations elsewhere, imperiling the company’s future.

Regulation also stands in its way of further growth. In the U.S., for example, building codes don’t allow for the kind of recycling that Holcim is allowed to do in Switzerland. Any U.S. client that wants to use recycled cement in its concrete construction can do so only with a workaround, the company told me. In the case of the Amazon warehouses, for example, the low-carbon cement had to be transported from Spain and then used to make concrete in the U.S. in order to comply with local rules. Holcim will need to convince more regulators that recycled cement is viable, or the company will face a big roadblock in its sustainability journey.

Jenisch’s focus is clearly talks with regulators rather than Holcim’s dealings in court. “I don’t think anyone can accept historical responsibility,” he said of the lawsuit by the islanders. “It’s more important what action we take now. This is what I want to be part of.”

But it’s all hands on the regulatory deck for Jenisch. This summer, Magali Anderson announced her departure as Holcim’s chief sustainability officer. Like her predecessor, Nollaig Forrest, the new CSO, has no training in engineering or safety. But she’s steeped in government affairs and communications, skills she honed at other industrial groups such as Dow, DuPont, and American fragrance maker Firmenich. Forrest’s main job now, she told me, is to get regulators to embrace Holcim’s vision of sustainability in construction, especially in the U.S. and the European Union, where Holcim gets the lion’s share of its sales. One tactic Holcim is considering, she said, is to convince regulators in a large, influential state such as California of the effectiveness of Holcim’s approach, with the aim of creating a snowball effect across the country. It has been a tried and tested method in regulation of other green technologies, including electric vehicles.

One stakeholder Forrest and her colleagues will still have to win over is Renovate Switzerland. It’s not that the organization doesn’t appreciate the efforts Holcim has undertaken so far. “From what we know, there is a lot of nice work, but [some of it] may be a false promise too,” Marie Seidel, a spokesperson for the organization, told me over the phone. Overall, the organization remains unconvinced that a company whose business model depends on cement and concrete can ever be a champion of a carbon-neutral world. “What our society needs right now is a complete U-turn in the way we consider the climate crisis,” Seidel said. “If Holcim would take this issue seriously, they would stop building buildings that emit CO2 at all, not 30% less.” For Renovate Switzerland, in other words, 2050 should start tomorrow.