Reimagining Construction: Is a Cement-Free Future Possible?

The construction industry is deeply reliant on concrete—a material celebrated for its affordability, fire resistance, and versatility, forming the backbone of modern architecture. Yet, this dependence comes at a steep environmental cost, with concrete production being a significant contributor to CO2 emissions. As the climate crisis intensifies, it’s time for the sector to rethink its ways and embrace more sustainable alternatives.

Balancing the Housing Boom with Climate Goals

The mantra of ‘Build, build, build’ echoes loudly in political circles as nations grapple with skyrocketing housing demands and limited supply. Research predicted that by 2024, the housing shortage will have worsened significantly, driven by growing populations. To meet this demand, hundreds of thousands of homes will need to be built swiftly—an immense task that challenges the capacity of many countries.

But the construction industry faces more than just logistical hurdles. The climate crisis looms large, with ambitious targets set by global agreements. The Climate Agreement mandates a 49% reduction in CO2 emissions by 2030, and by 2050, the construction sector must achieve complete carbon neutrality. This presents a monumental challenge, as construction currently accounts for an estimated 38% of global CO2 emissions.

As the sector races to build for the future, it must also reinvent itself to align with sustainability goals. The question is: can we meet the demands of a growing population while drastically reducing the environmental toll of construction? The stakes couldn’t be higher.

Tackling the Cement Industry's Carbon Crisis

Concrete, the world’s most-used building material, is also one of its most CO2-intensive culprits—and the blame lies squarely on its key ingredient: Cement. In 2022 alone, the cement industry released 1.6 billion tons of CO2, representing a staggering 8% of global emissions, rivaling the impact of oil and gas. If action isn’t taken to curb emissions, working in cement could soon carry the same environmental stigma as employment in fossil fuel industries.

While concrete’s advantages—affordability, flexibility, heat resistance, and availability—have made it indispensable, the environmental toll cannot be ignored. The solution? A shift toward biobased building materials, which are far more sustainable. However, this transition remains slow. Society’s reliance on technical materials like concrete is deeply ingrained, with biobased options accounting for just 3% of current material use. For now, concrete remains a necessity.

This makes it crucial to focus on cutting CO2 emissions in concrete production, leveraging innovations and sustainable practices. Whether through cleaner cement alternatives, carbon capture technologies, or new construction methods, one thing is clear: the climate goals must be met—with or without concrete. The future of construction depends on it.

Moving Beyond Industry’s Quick Fixes

A common approach to reducing CO2 emissions in construction is Carbon Capture and Storage (CCS)—a technique used across industries to "vacuum" CO2 from the air, storing it in tanks or old gas fields. While CCS offers a short-term reduction in emissions, critics argue it merely treats the symptoms without addressing the root cause of the problem. By relying on CCS, the industry risks maintaining its “bargain basement” practices, postponing the necessary transformation to genuinely sustainable solutions.

The real opportunity lies in rethinking concrete production—a process reliant on three core components: water, a binding agent (typically cement), and an aggregate (like gravel or sand). To truly reduce CO2 emissions, the focus must shift to:

1. Alternative Binding Agents: Replacing traditional cement with low-carbon or carbon-neutral alternatives, such as geopolymer binders or fly ash.
2. Recycled Aggregates: Incorporating reclaimed gravel, sand, and other materials to minimize the environmental footprint.

These innovations tackle the issue at its source, offering a proactive path to sustainable concrete. By reimagining how concrete is made, the industry can significantly reduce emissions while preparing for a future where sustainability isn’t optional—it’s the standard.

Sustainability isn’t optional—it’s the standard

A New Era for Sustainable Concrete

Leading the way in sustainable construction, Heijmans is proving that innovation and environmental responsibility can coexist. The company has been involved in numerous projects that prioritize more sustainable concrete, including the renovation of the Rabobank head office in Utrecht. Circularity was a core focus, with 100% recycled gravel and 64% recycled sand used in the concrete mix. This approach not only adhered to strict safety standards but also achieved a 36% reduction in CO2 emissions, setting a new benchmark for eco-friendly construction.

Similarly, the De Nieuwe Post government office in Arnhem is another groundbreaking project by Heijmans. Currently under construction, this project involves pouring 500 cubic meters of sustainable concrete, composed of 70% recycled materials. To further promote circularity, Heijmans is repurposing materials from the demolition of the old building for use in other local projects, ensuring that construction waste gets a second life.

These projects highlight the potential of recycled aggregates, such as gravel and sand, in reducing the environmental footprint of construction. By integrating waste materials into new builds, Heijmans is not only lowering emissions but also championing a circular construction model—an approach that could redefine the future of sustainable urban development.

Pioneering a Sustainable Cement Alternative

In 's-Gravenzande, construction company Heijmans demonstrated the potential of cement-free concrete by using an innovative material known as geopolymer concrete. Unlike traditional concrete, where cement acts as the primary binder, geopolymer concrete replaces cement with blast furnace slag and fly ash—residual by-products of the steel industry. These materials are chemically activated with alkaline liquids instead of water, resulting in a durable, sustainable alternative to conventional concrete.

Heijmans utilized this groundbreaking material to construct two homes, achieving a remarkable CO2 reduction of over 50% compared to standard concrete. This pilot project exemplifies the feasibility of cement-free construction, proving that, with innovation and commitment, the industry can move away from cement dependency.

The success of this project underscores the transformative potential of geopolymer concrete and offers a bold vision for the future of sustainable building. It’s a clear indication that cement-free construction is not just a dream but a viable reality, paving the way for a greener, low-carbon construction industry.

A Key to Carbon-Neutral Construction

You might ask: Why aren’t sustainable solutions the industry standard yet? It’s a valid question with a complex answer. The construction sector, though charming in its focus on longevity and durability, suffers from a significant inertia factor. Builders prioritize creating structures that stand the test of time, but this slow-paced innovation struggles to meet the urgent demands of a climate-conscious society. It’s a real challenge for an industry that needs to adapt quickly.

However, achieving carbon-neutral construction requires more than just circular concrete solutions. A crucial piece of the puzzle is scaling up biobased materials—renewable alternatives derived from natural sources like wood, hemp, and bamboo. The current reality is stark: we use four times more materials in construction than the usable waste generated. Without increasing the share of biobased materials, reaching sustainability goals will remain out of reach.

The path forward? Scaling biobased materials to 10–15% of the industry’s supply in the coming years. This shift could revolutionize construction by reducing reliance on resource-intensive materials while creating a more circular, climate-friendly future. Biobased materials aren’t just an option; they’re an essential step in redefining the way we build.

That's it for now. We'll be back soon with more Innovations in the Construction. Did you like this post? Interested in more? Feel free to like and/or share with your network.