We’ve made such strides in the technical aspects of construction in the last decade or two that it’s easy to make assumptions that turn out to be false.
In North America we’ve grown accustomed to thinking of the Athena Institute for Sustainable Materials, an Ottawa-based non-profit that champions Life Cycle Assessments (LCA) of building materials, as the last word on life cycles. And with the growth of environmental awareness, it’s easy to think that LCA underpins much of today’s building materials and structural systems. Until you open a recent book on the subject and read that "because of the relatively recent ‘introduction’ of Life Cycle Assessment . . . there are no comprehensive Life Cycle Assessments with real verified data for tall buildings."
The book — a research report, really — is titled Life Cycle Assessment of Tall Building Structural Systems, and it was published by the Council on Tall Buildings and Urban Habitat.
The council has been around since 1969, and kept a fairly low profile for the first years of its existence. Some felt it seemed uncertain what it should be or should be doing. Then, in 2006, the council appointed Antony Wood a British-trained architect, as executive director.
Since then, the group has been active on several fronts. Most importantly, it has an active research and publication program.
Although it is based in Chicago at the Illinois Institute of Technology, it also has an Asia office at Tongji University, in Shanghai, and a research office at Iuav University, in Venice, Italy.
That’s where Dario Trabucco, the group’s research manager, is based. He and Wood led a team of five authors in writing the report.
Skyscrapers have been around for a century, and they’re getting taller. The council defines "supertall" buildings as those more than 300 metres in height. "Megatall" buildings are those of more than 600 metres. As of last June, the world had 93 supertalls and three megatalls completed and occupied.
But, the authors note, with the exception the 9/11 attacks on the World Trade Centre, no one has ever actually demolished or dismantled a building taller than 187 metres. That was the Singer Building, a 187-metre tower in New York City that was demolished in 1968.
That means, say the authors, "We are building many hundreds of skyscrapers — in addition to those already in existence — with little idea about their real longevity, what variances and experiences they will have during their whole life cycle, and what will happen to them at the end of that life cycle."
This is an important issue that should influence the design of all skyscrapers, they write, "but the industry does not even have a template for assessing the relative implications — energy or otherwise — of the different stages of a building’s life."
They say that the industry has paid attention to energy-efficient operation at the expense of other considerations. Reducing the embodied energy of the materials in the building itself is equally important.
In short, "The true environmental impact of the full life cycle of tall buildings is a significantly unknown quantity."
That’s what this book begins to assess. There is so much work to be done that they’ve selected structural systems as a starting point, a bite-sized segment they could deal with in a three-year research project leading to this one 187-page report. They call it "a first stab" at the problem of quantifying the decisions made in the design and engineering process of skyscrapers.
So if you’re a design professional who is working on tall buildings, this book is aimed at you.
It’s available from the Council on Tall Buildings and Urban Habitat at www.ctbuh.org. Type Life Cycle Assessment in the search box.Pricing is in U.S. currency, so the price to Canadians will vary somewhat. With shipping included, I paid a little over $63 for my copy.
Korky Koroluk is an Ottawa-based freelance writer. Send comments to firstname.lastname@example.org.