Have you tried to understand the carbon footprint of a material or product and been frustrated not knowing which data to use? Tried to compare the environmental performance of similar products and been unable to find an apples-to-apples comparison?
These challenges and others are driving the development of Environmental Product Declaration (EPD) standards that integrate a comprehensive assessment of full lifecycle environmental impacts to enable reporting of the "environmental footprint" of a material or product. An EPD reports the results of lifecycle assessment (LCA) analyses (e.g., global warming potential, water use, etc.) in a consistent manner following agreed upon rules. These standards are being designed to be general enough to apply to all products – from clothing to curtain walls (ISO 14025, CEN 15804). Rules specific to the building industry (Product Category Rules/PCRs) are required to refine global EPD and LCA standards to address unique manufacturing, use and end-of-life conditions. In order to compare the environmental footprint of a material or product, one must be sure that consistent assumptions are made when the footprint is evaluated. Without category-specific PCRs it is not possible to create comparable EPDs; PCRs are in effect environmental accounting standards. If developed appropriately, EPDs can be appropriately used to compare products.
There is significant interest and activity currently underway in the United States to advance our ability to create building industry specific PCRs and promote transparency of information concerning the environmental impacts of building materials and products.
Architecture 2030 is a non-profit organization focused on addressing climate change by significantly reducing energy consumption throughout the building sector. The 2030 Challenge for Products is literally a challenge to all in the building industry to prioritize products that meet a maximum carbon-equivalent footprint of 30 percent below the product category average with a gradual reduction to 50 percent or better compared to current industry average by 2030. Along with this challenge, Architecture 2030 has developed resources to explain methodology and strategy, which are available online at the Building Green Information Hub (www2.buildinggreen.com/topic/2030-challenge). Building industry specific PCRs as well as industry benchmarks must be created in order to implement the 2030 Challenge for Products. Released in early 2011, this challenge has prompted interest by industries looking to meet the challenge, while providing leadership in advancing the understanding of EPDs in the U.S.
PCRs relevant to structural engineers
Given that the U.S. government is not taking a top-down approach for establishing these standards, industry and others must lead in shaping standards that are rigorous, transparent, equitable and meaningful. Per ISO standards, EPDs are managed and reviewed by "program operators." Program operators must be third party verified and can be industry trade organizations, non-profit or for profit agencies. In most European countries the government has established a national EPD system. In the U.S., there are multiple EPD programs under development. Two structural-specific PCRs are currently in development for concrete and wood. Manufacturers can use these PCRs to develop EPDs for their products.
The concrete PCR development was initiated by this author and funded by industry sponsors of the Carbon Leadership Forum. During 2011 a committee with representatives from the concrete industry, as well as practicing structural engineers and lifecycle assessment experts, worked to develop a draft PCR. Critical issues to address include: How to assess the environmental impact of products typically considered as waste; how to track and report water use; and how to reasonably reflect the variation/precision of results developed from industry average data. This PCR will be finalized soon.
A wood PCR was initiated by FPInnovations, a Canadian wood research institute (funded by industry and government). The final draft of this PCR was published in November of 2011. Further refinement of this PCR is under consideration.
With PCRs and EPDs in place, structural engineers will have better quality data to assess the environmental footprint of structural materials and systems and potentially have the opportunity to specify and/or prioritize lower environmental impact options. Engineers looking to provide leadership in this area should review and comment on PCRs under development. Adding non-industry specific perspectives is critical. Engineers looking to motivate the publication of better environmental performance data should begin asking suppliers for EPDs and consider adopting the 2030 Challenge for Products.
Kate Simonen is an Assistant Professor of Architecture at the University of Washington and director of the Carbon Leadership Forum, www.carbonleadershipforum.org, and a member of the SEI Sustainability Committee, www.seisustainability.org.