Engineering Inc. - Spring 2020 - 52

INTHENEWS

Thornton
Tomasetti's
Beacon tool,
an open source
Revit plug-in,
measures
embodied
carbon.

Thornton Tomasetti Releases
Embodied Carbon Study,
Open-Source Measurement Tool

n late 2019, Thornton Tomasetti released results
from an ongoing study into the extent of embodied
carbon in building structures, identifying the types
of structures, materials, and components that have the
highest carbon emissions.
The firm also released its Beacon tool (visit https://
core-studio.gitbook.io/beacon/), which measures
embodied carbon. The Revit-based tool
allows structural engineers to measure
the embodied-carbon impact of their
design choices at any point in the
design process.
The firm's embodied carbon efforts
began in 2011 when it joined the AIA
2030 Commitment, which aims to
meet the Architecture 2030 vision of
carbon-neutral buildings by 2030.
"We were asked to measure the operational energy use of our building projects, but that did not seem like the best
path for us because we were primarily
structural engineers at the time," says
Amy Hattan, vice president of corporate
responsibility at Thornton Tomasetti.
"Embodied carbon was where we had
the greatest impact on climate change."
The firm decided to focus on
embodied carbon and over the past
seven years has studied its impact on
more than 600 of its structural projects.
The firm defines embodied carbon as the material's
energy impact from the moment it is mined until it
leaves the factory gate. The impact can be significant.
For example, studies have found that the three most
commonly used structural materials-concrete, steel,
and steel rebar-account for more than 22 percent of

global carbon dioxide emissions. Furthermore, in a
typical building, 55 percent of the embodied carbon is
in the structure and substructure.
The study is ongoing, but key findings so far include:
* The increased use of recycled steel and fly ash in
cement has been the largest driver in reducing
embodied carbon over the past seven years.
* Almost all building types have the
highest proportion of embodied carbon in their slabs.
* Skyscrapers have the highest proportion of embodied carbon in
their columns rather than the
foundations.
* LEED-certified buildings have
slightly lower embodied carbon levels than non-LEED buildings.
* Steel buildings have more embodied
carbon than concrete buildings.
"That last one is not what people
tend to think," says Rob Otani, chief
technology officer at Thornton Tomasetti.
"Concrete is known as being high in
carbon dioxide emissions. The reason
it has that reputation is because it is by
far the most used material in the world.
But when we look at our projects, our
steel framed buildings tend to have more
embodied carbon."
One of the prime reasons for releasing the results of
the study is to drive home the impact that structural
engineering has on climate change, according to Hattan.
Given the pace of climate change, she says, "We
need to make dramatic changes in the next 10 to 15
years. Up to now, the focus has been on operational
energy efficiency, and that made sense because its

Thornton
Tomasetti
found that
in a typical
building,
55
percent
of the
embodied
carbon is in
the structure
and
substructure

"Reducing embodied carbon has the biggest
immediate effect because all of its impact is
in the early stages of a structure's life cycle."
AMY HATTAN
VICE PRESIDENT OF CORPORATE RESPONSIBILITY
THORNTON TOMASETTI
52

ENGINEERING INC.

SPRING 2020

https://core-studio.gitbook.io/beacon/ https://core-studio.gitbook.io/beacon/

Engineering Inc. - Spring 2020

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