Who do you think would win at the sustainability tug-o-war? Team safer materials or team low-carbon products?
Healthy Building Network (HBN) has often heard these two issues framed as a competition–a false choice. Instead, we know that these two powerhouses must work together for optimal results.
HBN and Perkins & Will recently published a study highlighting building products that can do just that: optimize material health and lower their carbon footprint. This study identified key drivers and paths towards low embodied carbon and safer materials as well as when to consider and optimize both at the same time. To illustrate this point, we plotted an actionable path for project teams using flooring products as an example.
Team Low-Carbon Products: The embodied carbon of building materials contribute a whopping 11% to global carbon emissions.1 Most of these emissions happen before that product even gets installed. Additionally, the poorest countries and regions are those most impacted in terms of damage and loss of life by the effects of climate change.2“That 11% might sound small compared with the impact of operational energy (28%), but for new construction, embodied carbon matters just as much as energy efficiency and renewables. That’s because the emissions we produce between now and 2050 will determine whether we meet the goals of the 2015 Paris climate accord and prevent the worst effects of climate change,” explains BuildingGreen’s recent report.
Team Safer Materials: We spend 90% of our time indoors, and hundreds of industrial chemicals are found in our indoor spaces— in the dust, in the air we breathe, and in our bodies.3 The health impact of building materials are not limited to their time in use in the building, they often occur during manufacturing, installation, and at the product’s end of life. People living in close proximity to industrial facilities experience persistently worse air quality than average and exposure to industrial pollutants disproportionately impacts people of color.4 A recent report suggests that man-made pollution has exceeded the Earth’s safe operating boundaries.5“Transgressing a boundary increases the risk that human activities could inadvertently drive the Earth System into a much less hospitable state, damaging efforts to reduce poverty and leading to a deterioration of human wellbeing in many parts of the world, including wealthy countries.” Professor Will Steffen, researcher at the Centre and the Australian National University, Canberra6
Reducing toxic chemical use and the emissions associated with building materials NOW is a vital sustainability strategy for any project team.
The Research: To identify the key drivers of embodied carbon and the key opportunities to reduce embodied carbon for each product type we read Environmental Product Declarations (EPDs), reviewed literature and data compilations, and conducted manufacturer interviews. The hazards associated with flooring products, the chemicals used to make those materials and the hazards associated with the chemicals used to install those products were collected using the HBN Flooring Product Guidance and hazard data in the Pharos database.
Embodied Carbon: Our research concluded that flooring products’ embodied carbon impacts are mostly associated with the raw material supply. The biggest opportunities to reduce embodied carbon in flooring comes from choosing a different product type that uses less impactful raw materials as well as products with longer service life. Carpet was consistently the most impactful product type due in part to its short service life. Plant-based flooring products, such as wood and natural cork, were consistently the least impactful.
Material Health: Not surprisingly, the biggest opportunities to avoid chemicals of concern in flooring come from choosing a product type with typically fewer chemicals of concern. Products made from plastic, such as vinyl, nylon, or polyurethane tend to use more hazardous chemicals during manufacturing, installation, use, and end of life, than mineral or plant-based products. Selecting a product that is yellow or above on the HBN Flooring Guidance, such as wood or linoleum, or even a non-vinyl resilient flooring will minimize the use of hazardous chemicals. Products in the red zone such as vinyl and carpet, are to be avoided.
Conclusion: When we looked at the opportunities to improve embodied carbon and improve material health for flooring we found that they were largely complementary.
- Use flooring with a long service life. Avoid products with a short service life, like carpet, and select a product with a long service life, like wood.
- Choose biobased product types. Linoleum, wood, and cork are all flooring product types that were identified as both resulting in lower embodied carbon and safer in terms of material health.
- If you must use carpet, avoid use of virgin nylon carpet product types. While carpet generally can contain more chemicals of concern than other product types, carpet made with virgin nylon as a generic product type was identified as having the highest embodied carbon within the flooring category.
- Use circular and safe materials. Use recycled content from known sources. Prefer products that have been tested for these chemicals and have below detectable levels or below levels that would be found in virgin resin content for these materials.
These findings highlight the importance of pre-emptive design. Parallel to the way we conduct early modeling for energy or water use, the industry needs to model for embodied carbon and material health. A materials modeling approach--where the entire team is engaged early - before design development or construction development - will enable educated decisions before the design is set. Use HBN’s Embodied Carbon and Material health in Flooring and Drywall report and tools like HBN’s product guidance and the Carbon Smart Materials Palette to select typically healthier, low-carbon building product options.
 Architecture 2030. “Why the Building Sector?” https://architecture2030.org/why-the-building-sector/
 United Nations. “The Sustainability Development Goals Report 2019”. 2019. https://unstats.un.org/sdgs/report/2019/The-Sustainable-Development-Goals-Report-2019.pdf
 Goodman, S. “Tests find more than 200 chemicals in newborn umbilical cord blood”. Scientific American. December 2, 2009. https://www.scientificamerican.com/article/newborn-babies-chemicals-exposure-bpa/ Environmental Science Technology. “Consumer Product Chemicals in Indoor Dust: A Quantitative Meta-Analysis of U.S. Studies”. 2016. 50, 19, 10661-10672. https://pubs.acs.org/doi/full/10.1021/acs.est.6b02023
 Chandra, A. et al. “Building a National culture of health. Background, action framework, measures, and next steps. RAND Corporation. 2016. https://www.rand.org/pubs/research_reports/RR1199.html
 Persson, L. Et al. “Outside the safe operating space of the planetary boundary for novel entities” Environmental Science and Technology. 56. 5. 1510-1521. 2022. https://pubs.acs.org/doi/10.1021/acs.est.1c04158
 United Nations. "Scientists Say Planetary Boundaries Crossed." 2015. https://unfccc.int/news/scientists-say-planetary-boundaries-crossed