How Choosing a Low-Carbon Concrete Can Help Fight Global Warming 

Several Canadian organizations are collecting carbon from various aspects of the creation of cement and using it to create concrete.   

Concrete has long been the poster child for environmental impacts. While its impact is widely known, its use is even more widespread. In fact, according to an ICEFA study, concrete is the second most used substance after water.  

Its significant contribution to GHG emissions is also widely reported. Most recently, a report from the Global Alliance for Buildings and Construction noted that concrete alone is expected to contribute to 12% of global GHG emissions by 2060.  

Undeniably, low-carbon concrete material innovation and procurement across the building and construction industry is critical for emission reduction efforts. While recent news and industry initiatives to reduce the emissions of concrete are promising, it’s time the architecture and design community at large begins to understand, evaluate, and select low-carbon options in the fight against global warming.  

Fortunately, there are tools, products and policies that exist to support the industry in the significant need to reduce concrete’s impacts.   

Putting the Right Policies in Place  

When it comes to enacting widespread industry adoption of new sustainability-driven practices and principles, policy efforts are an important step. In Canada specifically, the government is already enacting critical policies to accelerate climate action, including efforts related to concrete.  

In fact, the Government of Canada’s A Healthy Environment and a Healthy Economy plan, which launched in December 2020 and endeavors to build a better future, includes specific messaging on the need for low-carbon cement to develop a robust, low-emission building materials supply chain.   

Even more noteworthy is the Government of Canada partnering with the Cement Association of Canada to create a roadmap to achieve net-zero carbon concrete by 2050, which aims to be complete by December 2021, and is in line with the goals of the previously mentioned climate plan. Specific ways that the partnership might achieve this goal include the development of low-carbon materials with innovation and procurement, the validation of products with next generation technologies and engagement with critical stakeholders to reduce emissions in the sector.    

These policy efforts are increasingly critical in driving and creating a case for low-carbon procurement. However, as we continue to see and experience the impacts of climate change, industry continues to act and decarbonize regardless of policy. This includes the introduction of low embodied carbon concrete options and new tools that support the comparison and specification of these alternatives.  

Tools and Innovation at Play  

As the Government of Canada enacts policies that drive and encourage low-carbon concrete innovation and research, it’s important to highlight those companies already offering these materials with lower carbon. These organizations are collecting carbon from various aspects of the creation of cement and using it to create concrete.   

In fact, Canada’s own CarbonCure is one of the companies rethinking how concrete is made. The company partners with concrete producers around the world, installing technology that sequesters recycled carbon from industrial sources like plants and factory exhausts and injects it into fresh concrete where it is permanently embedded. Notably, this innovation makes the concrete a stronger material and typically reduces carbon emissions by an average of 25 pounds per cubic yard.

Beyond these carbon sequestration technology efforts, other cement industry leaders, like Lehigh Cement, another Canadian-based company, are blending cement with limestone to reduce the carbon footprint of its cement mixes. This new product, EcoCem PLUS, is blended Portland Limestone Cement (PLC) and has a carbon footprint 32% lower than the current industry average for general use cement.  

As more companies focus on developing and commercializing these low-carbon concrete options, architects and designers are also realizing their purchasing power when it comes to the procurement of materials with lower embodied carbon impacts. As they aim to procure low-carbon solutions in an effort to reduce the emissions of their built spaces, the Embodied Carbon in Construction Calculator (EC3) is a free, easy-to use-tool that allows benchmarking assessment and reductions in embodied carbon per material category, including concrete.   

The solution utilizes building material quantities from construction estimates and/or BIM models and a robust database of digital, third-party verified Environmental Product Declarations (EPDs). Powered by this data, the EC3 tool can be implemented in both the design and procurement phases of a construction project to look at overall embodied carbon emissions, enabling the specification and procurement of low-carbon options.    

Notably, EC3 continues to see interest among the industry specific to the concrete category. In fact, there were over 28,000 searches of the concrete material category in just a six-month window. In addition, there are currently more than 40,000 concrete-specific EPDs within the tool, marking the significant industry response and understanding of the need to reduce emissions for this material category. 

In markets where concrete suppliers have adopted on-demand, mix-specific EPD generation, performance-based concrete specifications coupled with bid document language requiring EPDs at time of bid has catalyzed suppliers to optimize both the carbon and the price of their concrete. In 2020, this led to, on average, a 30% reduction in carbon emissions against a typical mix, at no additional costs or impact to projects.  

How Architects & Designs Can Take Action 

The collective impacts of new policy, product innovation and readily available technologies for low-carbon concrete will continue to drive demand and incentivize manufacturers and suppliers to invest in material innovations that reduce the carbon emissions of their products.  

It’s critical that architects and designers begin to assess the embodied carbon of their projects beyond just concrete and utilize these new opportunities for improvement to affect change across an industry that is responsible for nearly 40% of global GHG emissions, according to Architecture 2030. By using tools like EC3 to demonstrate the embodied carbon impacts of projects to owners, as well potential opportunities for reductions, AEC professionals can drive transformation across the industry.   

A recent example of architecture firms engaging with these tools is Perkins&Will teaming up with C Change Labs and Building Transparency (co-conceivers of EC3) to develop a next generation carbon reduction tool to make it easier for designers to understand the climate impacts of their material choices. The team recently received a $460,000 CleanBC Building Innovation Fund (CBBIF) grant from the Province of British Columbia to support its efforts.  

This industry represents a significant opportunity for mitigating carbon emissions and achieving zero-carbon, resilient spaces in our collective efforts to reverse global warming.