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Green Guide to Green Build - LCA Impact: Life Cycle Assessment: Out in the Open

A look at how LCA information can become more accessible, transparent and dynamic.


A look at how LCA information can become more accessible, transparent and dynamic.


  1. The ISO 14000 series of standards includes global standards on life cycle assessment, recently updated.
  2. The Swiss government has invested the required resources during the past  30 years to achieve today's "EcoInvent" database (  In 2001, U.S. agencies partnered with private industry to launch the U.S.  LCI database (

By Greg Norris 

It is hard to be awake these days and not feel the change. People, lots of people, are taking a whole new look at their relationship with the planet. There are explosive new levels of concern about climate change, and a rising sense that all of us need to play a role in addressing it. Mainstream Americans are starting to think and ask and care about our own "climate footprint," and about our impact on the planet. We are taking it personally. And this all-important step is driving our employers and vendors to do the same.

Green design and procurement of the built environment is practically a universe of activity in its own right. This massive effort that we often simply label "green building" has been laying the foundation (pardon the pun) for the present popular explosion in environmental consciousness for well over a decade. And green building sits in a "feedback loop" with this ebullient growth: having helped to foster it, green building now finds itself further surging in response to it.

We know that achieving the smallest possible environmental footprint (or even a state of net positive impact!) during the long and important operational life of a building is "job one" for green building. We also know that it takes massive supply chains with a myriad of products and materials to enable construction, and as operational footprints get smaller, the importance of these supply chains in the total picture of a building's impact looms larger.

These facts have helped to focus much of the attention and creativity on the tasks of designing, constructing, and furnishing our built environments out of materials and products whose entire production chains and useful lives place the minimum possible burdens on the environment, and pose minimum possible risks for human health. How do we understand, quantify, and compare the environmental and health consequences of these thousands of supply and production chains, in a practical, useful and affordable way to support green building?

Life Cycle Assessment or "LCA" (described below) is a data-driven approach to help meet this need. As we will see, LCA is a standardized method, and it has lead to the creation of major data resources that help us design and procure green buildings. At the same time, we will see that the surge in the need for this information puts new pressure on LCA information to flow much more effectively, transparently, dynamically, and at a greatly reduced cost. This article briefly surveys some ways in which LCA information is getting "out in the open" to help us all get the necessary job done: radically shifting the environmental and health impacts of the built environment from negative to positive.

This morning you likely showered, ate breakfast, and might have traveled to work, probably in a car. Even if you telecommute, look around your home office at the goods powered by electricity; or at the furniture on which they all sit-and on which you sit. Are you beginning to imagine supply chains? (E.g., factories in Asia which produced your computer and printer; power plants in your region which are generating your electricity; paper mills in North America which made your printer paper; factories, perhaps in the United States, which produced the trucks that shipped your office supplies; farmers in South America who grew the beans for your coffee ... etc.)

Mainstream attention to climate change is helping mainstream folks increasingly think in terms of "footprints" and "embodied environmental burdens." We are realizing that everything we buy has a story behind it. This thinking in terms of the stories behind our purchases is helping us to realize that the influence of those purchases extends way beyond the final producers of goods and services. Many of the most important social and environmental impacts occur further up the supply chain, often in countries beyond our borders. For some products, major impacts occur during the usage phase and/or disposal phase of the life-cycle as well.

Back in the late 1960s, folks in the United States and in Europe started asking themselves about such stories behind the life-cycles of beverage containers. They noticed a shift underway, from returnable bottles to "one-way" (disposable) packaging, and wondered what this shift might mean for issues like energy use, solid waste and pollution. In an attempt to provide quantitative comparisons of the environmental "stories" of different
packaging alternatives, the method of Life Cycle Assessment was born.

Life Cycle Assessment (LCA) is now an ISO standardized approach for quantitatively summarizing environmental impacts over product supply chains and life-cycles.1 The range of environmental concerns addressed by LCA is designed to be comprehensive, including impacts on human health, ecosystems, climate and resources. LCA addresses impacts attributable to emissions in air, water and soil, as well as extractive flows from the environment. More recently, LCA is being expanded to address social issues in supply chains and life-cycles as well.

Today's LCAs are done primarily by, and for, large organizations. This is because LCA requires extensive databases and the use of specialized modeling software. The databases are comprehensive- containing data on thousands of interconnected unit processes, with each process using specified quantities of inputs from nature and from other unit processes, and most processes also emitting specified quantities of many different pollutants to air, water and land. These comprehensive databases require millions of dollars and many years to create, and they must then be kept current.2

The standard approach to LCA database development has followed the standard model of Web database creation: a centralized, provider-driven effort. The creator of an LCA database sends detailed questionnaires to a representative sample of companies that produce a particular product of interest. This research institute or consulting firm gathers and aggregates the data from the different companies, performs important quality assurance and error checking, and then generates data on the average production of the product.

Web 2.0, the paradigm of "bottom-up," user-driven content development, illustrates a whole different approach to LCA data development and use. As in other areas of information creation and sharing, the shift from provider-driven data to user-created data has the potential to create vastly richer data resources while also democratizing access to, and use of, the information. The data sources for LCA can be richer in at least two key ways: First, they can cover a much wider fraction of the goods and services sold in the economy; and second, they can be brand-specific.

What if organizations anywhere in the world could use the Web, at no cost, to select any product category, select the sustainability indicators that matter most to their organization, and then quickly compare relevant alternatives on the basis of internationally-standardized, comprehensive, transparent and validated life-cycle information? What if companies anywhere in the world could also freely compute their products' LCA results, benchmark themselves versus industry averages, and voluntarily report their LCA results on the Web. With these two capabilities, we
would have no-cost, bottom-up LCA reporting, and no-cost, universal access to product-specific LCA results. A nonprofit, open source project, start-up funding from a consortium of companies, public agencies, and nonprofit organizations-is working in collaboration with other projects to make these goals a reality.

The industry-average, institute-generated LCA databases described above are a necessary foundation on which systems like Earthster can be built. Because of their vast scope and resource-intensiveness, and also to protect competition-sensitive information, these databases contain data on generic processes and products-industry averages—not brand-specific information. Purchasers lack access to LCA information on specific products. Indeed, for many products, even generic information is not yet available, and certainly not brand-specific information. And up until this point in time, the primary way to generate such information has been to hire consultants or use specialized commercial software.

The Earthster project is creating open source software, which enables manufacturers to rapidly and confidentially create an LCA of their products. Manufacturers input their data (on their own computer, maintaining confidentiality) about the required inputs and emissions associated with production. The tool then gets the best available LCA data from the Web for each purchased input. Companies can use generic data, or if their suppliers have already published in Earthster, link to supplier-specific data- without publicly divulging supplier identities. At this point,
companies can compare their product's LCA with the average that is documented in LCA databases. If they like how their products compare with the average, they click to publish the LCA data for free on the Web.

Third-party validation is key to the credibility and accuracy of the LCA results calculated and published on the Web via Earthster. A nonprofit organization called The Green plans to fund the development of a protocol for third-party validation of this data. The validation protocol will harmonize, to the maximum extent possible, with existing and forthcoming protocols for validation of greenhouse gas footprint reporting.

Earthster enables users to calculate the total upstream life-cycle (inventory and impact assessment) results. However, it does not provide all the features of professional LCA software packages, such as making the entire chain of upstream unit processes visible and configurable. Companies who wish to have this capability need to also obtain LCA software. Fortunately, another open source project called "OpenLCA" is developing open source LCA software. And The Green is funding a project to ensure that OpenLCA and Earthster can exchange data with one another, so that users of OpenLCA can export their "gate-to-gate" results to Earthster (e.g., for a complex set of processes within their plant or company which produces a single product), and so that they can also identify data published in Earthster by current or prospective suppliers, and work with this data in OpenLCA.

Systems like these are bringing the ability to generate and share life-cycle information about products into the open. They are helping to make it possible for manufacturers to generate and share information that building designers and specifiers are increasingly calling for, in their efforts to build green. They also enable manufacturers to better understand their own supply chains, and to make-and report- continuous environmental progress.

The U.S. Green Building Council is helping to fund advancements to the Earthster interface so that manufacturers of building materials are better able to calculate and report product-specific, brand-specific life-cycle inventory results on the Web, drawing on the U.S. LCI database ( and other modular, transparent upstream databases. The Texas Commission on Environmental Quality is funding advancement of the Earthster interface that supports life-cycle-based "Environmentally Preferable Purchasing." Users will be able to compare products based on published LCA results, and to calculate and report benefits of improving their purchasing.

Importantly, these new, emerging abilities to generate and report brand-specific product information will also provide feedback to help grow and to continually update the important foundational public data resources, such as the U.S. LCI database that contains unit process data for generic or industry average production. Sharing information is the key. Making such sharing safe, credible, transparent and low/no-cost will help us all to do our necessary parts in fueling the green building revolution, for the sake of our descendants and our living planetary home.

 Greg Norris, principal, Sylvatica
manager, LCA into LEED, USGBC