Life Cycle Assessment: Making It Understandable, Usable & Real

Posted on: March 3rd, 2009 by Barbara Campagna

LCA will help us show how demolishing a historic hotel - like this one in Miami Beach - and replacing it with a new one will negatively impact the environment much more than just renovating it.

I recently had the honor of being invited to the Life Cycle Inventory Database Stakeholders Meeting at the Department of Energy. This group has been meeting for the past five years to develop the Life Cycle Inventory Database – the American version of some very effective tools that have been in place in Europe for many years now. The National Renewable Energy Laboratory (NREL) is managing this database and project.

Now, I will admit, I smugly admire my own intelligence at times, but this was a place where I was so intellectually out of my league, I had to leave the room a few times just to keep from hyperventilating! It’s good to be humbled sometimes.

Important Note: The rest of this post is highly technical. If you can’t get through it, feel free to just jump to the bottom paragraph. It’s okay; I won’t be offended!

What is life cycle assessment?

Life cycle assessment (LCA) is a scientific methodology to calculate the environmental performance of a product, material or building over its full life cycle. LCA evaluates all stages of a product’s life from the perspective that they are interdependent, meaning that one operation leads to the next. LCA enables the estimation of the cumulative environmental impacts resulting from all stages in the product life cycle, often including impacts not considered in more traditional analyses (e.g., raw material extraction, material transportation, ultimate product disposal, etc.). By including the impacts throughout the product life cycle, LCA provides a comprehensive view of the environmental aspects of the product or process, as well as a more accurate picture of the true environmental trade-offs in product and process selection. (This definition is from an article entitled “Life Cycle Assessment: Principles & Practice” by Scientific Applications Internationals Corporation of Reston, Virginia.)


If LCA of this terra cotta walrus on the Arctic Building in Seattle seems complicated, imagine how complicated whole-building LCA is.

For example, look at this terra cotta walrus from a famous Seattle building. Performing LCA just of this walrus would measure the energy and its impacts on the environment, including what it took to dig the clay from the ground that was used to make the terra cotta; the impacts of the manufacturing of the terra cotta; the packaging and transportation of the walrus to the building site; the energy and impacts it then took to affix it to the building; and the amount of energy and materials used over its life to maintain and restore it.

If that sounds really complicated just to measure this one walrus, imagine how complex it is to determine this information for an entire building. It boggles the mind.

Is the greenest building really the existing one?

Okay, so here I am in a room with the leading scientists in North America – perhaps even the world – on LCA. Frankly, just getting a seat at the table was a huge accomplishment for us and the preservation movement in general, as most of the people in this group have been working on this topic for many years. When we were going around the room saying what our experience and interests in LCA and the database were, it was apparent that my elevator speech was quite surprising to most people: “Existing buildings contribute almost 50% of the greenhouse gas emissions in the U.S., and therefore, it’s imperative to be able to measure the 'avoidance impacts' of keeping an existing building and not building a new one, and being able to measure LCA and understand the durability for existing materials and buildings is key to this." Some people at the table looked at me like I had three heads. Some smirked patronizingly like, "Isn’t she cute?" But a handful of attendees (and not necessarily the ones I thought) supported the idea and recognized it is a valid goal. One of the attendees - someone who typically works with us preservation-types - prefaced his reporting about my comments back to the group with, “Well, the preservationists like to say, ‘the greenest building is the one already built,' which I don’t necessarily buy…”

That's when I knew it was going to be a tough day.

Why do we think LCA is so important?

Here’s the problem: there are no statistics yet to prove what we anecdotally think should be so apparent, which is if you reuse an existing building, you save all the impacts that building a new one would inflict on the planet. But as Wayne Trusty from the Athena Institute (a leader in LCA) has said, "While it may seem intuitively obvious that retaining and renovating older buildings has environmental merit, the case is difficult to prove without access to the appropriate data and tools." And quite simply, LCA is the one agreed-upon tool to prove what seems obvious.

But other than us, there is almost no one out there who sees the need for conducting the research to figure this out. The U.S. Green Building Council (USGBC) is really the only one currently doing it with the creation of their Life Cycle Credit Calculator, which is part of the Alternate Compliance Path Pilot Program in LEED 2009 (see my previous blog on this and a recent article I wrote for the AIA Newsletter). That’s why developing a research agenda around LCA for existing and historic materials and assemblies (which can ultimately contribute to the ability to complete whole-building LCA and help us compare the environmental impacts of new building versus reusing an existing one) is so important.

The LCI Database Road Map


If we understand the impacts of demolishing buildings on the environment through the use of LCA, maybe demolition of buildings like this on K Street in Washington, D.C., will occur much less often.

The LCI Database is a partnership between public and private entities to develop a database for commonly used materials, products and processes. The Department of Energy is the primary supporter, with additional support provided by GSA, USDA, EPA, NIST, the Navy and USGBC. The first meeting of the group occurred in 2001, and the database went live in 2003. Unfortunately, very little has been done to the database in the past three years because of a lack of funding, but that’s all changing with the stimulus package, which is providing eight times more funding almost immediately. The purpose of this meeting then was to develop a roadmap for the database.

Beyond feeling like the poor cousin at the kids' table, I was quite intrigued by the range of industries involved. The purpose of the database is to create commodity-level manufacturing data for commonly used materials and products using industry averages, unit processes, and measuring from cradle to grave. And it’s not just about buildings. There were people from the biofuels industry, carpet manufacturing, the wood industry, packaging, steel and even medical waste.

The major drawback I observed of the current database is that it has developed reactively at the pleasure and leisure of the industry trade associations and private sector scientists who are encouraged to post their information, and there does not seem to be a proactive plan to develop the data outside of what industries are volunteering. Actually conducting the research to develop the data is highly specialized and as such pretty expensive. The industries with the money are the ones doing it, and they don't necessarily want to post it for free. So much of it is considered proprietary (ah, the beauties of capitalism). I hope that the addition of all this new stimulus funding will improve this approach, allow NREL to be more proactive, and maybe even fund some of these trade associations and private scientists.

We did develop a list of priorities, and this “road map” will be circulated to all of us in the next month. I will continue to report on this and remain hopeful that in future blogs I can report progress of getting historic materials and assemblies added to the priority list. Also, know that the National Trust is in the midst of preparing a retreat to develop our own research program, as we are in essence the trade association for the existing materials and buildings.

One note, if you do go to the LCI database and inventory, don’t expect to have a clue about how to use the data unless you are a life cycle scientist. Really. No kidding.

Like what you see? Join Barbara Campagna on her new National Trust historic sites blog, True Green. It's here that she will regularly discuss the innate green-ness of historic sites, as well as how green housekeeping and sustainable practices can impact historic sites and be seamlessly integrated into all actions and activities. So, make sure you add True Green to your blog roll, and if you want to contact her, always feel free at

The National Trust for Historic Preservation works to save America's historic places. Join us today to help protect the places that matter to you.

Barbara Campagna

Barbara A. Campagna, FAIA, LEED AP BD+C was formerly the Graham Gund Architect of the National Trust in the Stewardship of Historic Sites office. She is currently a sustainability consultant to the National Trust and can be reached at