Our built spaces have a significant impact on climate change – in fact, the building and construction industry is responsible for nearly 40% of global greenhouse gas (GHG) emissions. In Canada, specifically, homes and buildings account for 18% of national GHG emissions.
While these emissions might typically be associated with operational carbon, or the GHGs emitted during the use of a building, like electricity and natural gas, it’s the embodied carbon emissions that architects and building professionals also need to focus on.
Embodied carbon is the carbon footprint of a material and considers all GHGs emitted throughout the product’s supply chain, installation, use, replacement and end-of-life disposal. It also may represent 90% of total building-related emissions by 2050 if the industry keeps moving toward net-zero operating carbon but does not address embodied carbon.
To effectively reduce embodied carbon emissions, building industry professionals, including architects and designers, must prioritize low-carbon material procurement for their projects. And to do this, product manufacturers and suppliers can invest in transparency efforts to help provide visibility into the footprint of materials and products.
Luckily, there are tools and resources available today for this to happen, but it has been a long road to get to the level of material transparency we have today.
The Past: Understanding Obstacles for Material Transparency
Today, the building industry is aware of its climate impact, and we’re seeing the topic of carbon emissions come to the forefront of decision-making when it comes to materials.
Where architects used to focus on aesthetics alone, we continue to see more emphasis placed on evaluating the carbon footprint of a product. Individuals can source tools and data efforts, like Environmental Product Declarations (EPDs) and Whole-Building LCA tools, to learn more about a product’s carbon impact. However, it hasn’t always been easy for architects and other design professionals to access data and make informed material choices.
About 20 years ago, there was limited carbon data for materials available. And what was available was limited and clunky, meaning those with limited knowledge of the types of information included could not analyze the data for procurement decision-making.
At the same time, the emissions-related data available was typically a single data point for a whole material or product category. For example, we only had one average data point for steel or concrete. But, as we know, there can be significant variance between individual products within a category subset based on the manufacturer and their investments in low-carbon material innovation.
All in all, this meant that architects had limited tools to lower the carbon footprint of their projects – they often need more granular insights into specific product impacts to meet sustainability, aesthetic, and performance benchmarks.
Today, we have EPDs, technical documents that report on the carbon footprint of a product, that help the industry analyze the carbon emissions associated with a procurement decision, new buildings, and retrofits. These can help designers, architects and other construction companies directly measure, compare, and reduce embodied carbon related to products with specifications closer or exactly as they were put into their projects, as they can provide insight into environmental impact of more specific products and for specific manufacturers.
Our industry is continuing to make it easier to have visibility into the carbon impact of products by standardizing EPD reporting methodologies. Currently, the global EPDs available have different formats and include varying information, so it can be labor intensive to look at multiple documents, align them, and compare them efficiently.
To combat this, digitized EPDs within free and open-access tools have made it easier to compare data while the industry continues to invest in and prioritize standardization efforts to make evaluating data quicker and simpler.
Today: How Architects Can Incentivize Low-Carbon Products
Oftentimes, architects are the ones specifying products for a given project, so they have a significant amount of decision-making and purchasing power when selecting low-carbon materials. As they begin to drive demand for low-carbon solutions through green procurement, they are incentivizing construction materials manufacturers and suppliers to invest in disclosure, transparency and material innovations that reduce the carbon emissions of their products.
To do this, architects need to think about embodied carbon goals and benchmarks early in the project to ensure they are prioritized across the various design and procurement stages. This means asking manufacturers for EPDs or being transparent with suppliers that they will only choose a product if they have EPDs available. This will drive further investment in making climate-related data available and standardized, which will help designers choose the lower or lowest carbon options available in the long-term.
By requiring EPDs from manufacturers, designers and architects can drive awareness of embodied carbon and the importance of understanding the carbon footprint of products. Once we have widespread use of EPDs across product categories, it will be even easier to set carbon reduction goals and benchmark thresholds.
Similarly, providing a larger set of data across different categories helps the industry at-large understand the significant difference between choosing one product over another when it comes to carbon. Understanding the nuances of carbon reporting and impacts will help drive further efforts to invest in transparency and lead the industry to better align on methodologies and reporting in the future.
It’s critical that the building and construction industry select low-carbon materials if we’re going to reduce the carbon impact of our buildings. New tools and practices continue to make this easier, but we need all those involved in the overall lifecycle of a project to drive large investment in EPDs and set embodied carbon reduction goals early on in a project to make it easier to conduct early whole building life cycle analyses as well as prioritize low-carbon materials procurement. All these things together can help drive awareness, education, and action in understanding embodied carbon’s role in climate change and addressing its impacts.
Vaclav Hasik is Data Manager at non-profit agency Building Transparency, which developed and manages the Embodied Carbon in Construction calculator (EC3).