The industry is fighting climate change with wood, Lego bricks and new materials

The problem of stolen manhole covers in Turkey may seem an unlikely starting point for a new way to help buildings withstand earthquakes and address the construction industry's environmental problems. But when a Turkish businessman heard about a new material that prevented theft, he had an idea.

Cast iron is traditionally used to make manhole covers that protect drainage systems. But in 2010, there was a spate of thefts of scrap metal covers in Turkey, necessitating the use of an alternative made from equally strong material to secure them. And when Engin Yesil read about this super-strong composite material in news reports, he wondered whether it could be used to build buildings that could withstand earthquakes – a significant risk in Turkey.

Yesil began producing the composite material called Renco (short for “renewable composite”), which is made from up to 40% reused materials such as resin and fiberglass. Since 2011, more than 200 buildings have been built in Turkey using Renco blocks, which fit together like Lego bricks and are attached with glue.

Yesil wondered if Renco had potential in the United States, and after more than a decade of research and testing, Renco was used to build an apartment complex in Palm Springs in 2023.

In addition to being able to withstand catastrophic Category 5 hurricanes (the highest rating on the Saffir-Simpson hurricane scale and a growing phenomenon due to climate change), Renco claims to be more environmentally friendly than other building materials. According to a 2023 UN report, the construction sector is “by far” the largest greenhouse gas emitter of all sectors, accounting for 37% of global emissions.

According to a report commissioned by Renco from the Athena Sustainable Materials Institute, Renco weighs about 80% less than concrete, meaning more of it can be transported per truck, and also has 82% less carbon than structural steel. Embodied carbon refers to the emissions released during the production, transport and disposal of building materials.

According to Patrick Murphy, Managing Director of Renco USA, Renco is also 100% recyclable. He said the new composite represents a step change in building materials. “In construction, there are basically three ways to build, right? You've got concrete, steel and wood, and it's basically the same thing for 100 years… so this is really the fourth type of construction that's been approved,” he told CNBC via video call.

This year Renco will begin production in the USA for the first time. A factory will open in Florida in the coming weeks that can produce enough building blocks for around 9,000 medium-sized apartments.

As with other materials used in construction, Renco is not without its impact on the environment: while the Florida factory is being completed, blocks are currently being shipped from Turkey to the United States. And while Renco's Turkish production facility runs on renewable energy, about 12% of the electricity generated in Florida comes from nuclear power plants.

Renco is not the only company striving to build more sustainably. Across the Atlantic, a British company is designing buildings from a familiar material – wood. Architectural firm Waugh Thistleton designed its first cross-laminated timber (CLT) building in 2001 and has since built around 30 across the UK, Europe and the US. Products used are certified by the Forestry Stewardship Council or equivalent certification, meaning wood must come from forests that are managed in a way that meets a set of internationally agreed standards.

According to a 2024 study from the University of Arkansas, building with wood instead of steel or concrete could result in a 19% reduction in emissions, while a 2023 UN report is urging the construction industry to switch to bio-based building materials such as sustainably sourced Switching to wood and bricks to decarbonise the built environment.

“The idea that we can build from renewable materials has become increasingly important to us,” said Andrew Waugh, founder and director of Waugh Thistleton. “And then the more you do it, the more you realize that there are health and wellbeing benefits, that people are actually much happier and healthier when they're surrounded by natural materials than when they're surrounded by ceiling tiles Styrofoam and…drywall would be surrounded.” [wall panels]” Waugh told CNBC via video call.

But the UK has been slow to adopt wood as a building material, which Waugh says is “frustrating”. According to a 2022 government report, around 60% of waste produced in the UK comes from the construction industry, while Waugh notes this When building with wood, little waste is created on site. Here, too, building with wood is not without environmental concerns: the wood used in Waugh Thistleton's projects is often transported from Europe.

Another phenomenon caused by climate change is the rise in sea levels – while the land is sinking at the same time.

In the independent coastal state of Monaco, known as the playground of the rich thanks to its low taxes, a newly built “eco-district” called Mareterra has put sustainability at its heart. “With climate change, building on water is becoming a strategic approach for certain coastal areas,” said Guy-Thomas Levy Soussan, managing director of Mareterra Development, in an email to CNBC. The development is intended to be a “model” for how coastal cities can grow responsibly, Levy Soussan added.

During construction, the so-called “caisson” method was used, in which 27-meter-high reinforced concrete structures were erected in the French city of Marseille and floated to Monaco so as not to disturb marine life. Not only do they serve as flood barriers, but they also provide habitat for marine organisms, Levy Soussan said.

So-called “eco-reef villages” have also been built. They consist of more than 300 modules and were installed in the marine area where the development is located. Ecological “corridors” allow fish to reach villages, while a protected species of seagrass called Posidonia has been relocated to create an ecosystem. These environmental measures will be monitored for at least a decade and the government of Monaco will use the findings to guide future maritime projects, Levy Soussan said.

Both Waugh and Murphy expect the construction industry to switch to more sustainable materials.

“This is inevitable because the better other industries get at reducing their carbon footprint, the more exposed construction becomes an outlier,” Waugh said.

Regulation could be the force the construction industry needs to become more sustainable, Waugh Thistleton founder added.

The UK Green Building Council has called on the British government to further push its environmental targets for new homes, while in Singapore, for example, the government has added proposals to its mandatory energy improvement scheme to include older buildings. So far the focus has been on new buildings or extensively renovated buildings.

Murphy said the industry will need to “reduce” its emissions. “The industry has flown under the radar in a lot of ways, right? People talk about planes and cars and cows, you know, and lots of other… emissions. Many people don’t realize how bad cement is and how bad the built environment is.”

Embodied carbon has been a focus of the U.S. Environmental Protection Agency, and construction company Skanska USA has developed a tool called EC3 to help construction projects quantify their emissions.

Steve Clem, senior vice president of project planning and sustainability at Skanska USA Building, said the tool has encouraged some suppliers to reduce their carbon footprint.

When Skanska evaluated concrete companies for a large project in Seattle, it used EC3 to show each company how its materials compared to other companies in terms of embodied carbon. “As various suppliers saw how their blends compared to one another, they voluntarily took steps to improve their blends at no cost to the consumer,” Clem told CNBC via email.

The Vice President looks positively to the future. “The construction industry is doing more for sustainability today than at any time in history, or at least since the Industrial Revolution… My hope for the future is that sustainable construction is the norm and many more people have the opportunity to live, work and build “play” in zero-carbon buildings,” said Clem.