Thursday, April 23, 2020

Achieving Net-Zero Embodied Carbon in Structural Materials

Published research from local institutes to international panels are stating the importance of reducing carbon emissions to net-zero by 2050. Currently, building construction accounts for over 10% of CO2 emissions, with many of those emissions contributed from structural materials like steel, concrete, and timber. Additionally, according to the Global Alliance for Buildings and Construction’s 2019 Global Status Report, the global building stock is set to double by 2050. Therefore quite the challenge is presented to structural engineers to achieve net-zero carbon buildings to meet societal needs by 2050. To address this challenge, the Structural Engineering Institute’s Sustainability Committee has recently published a white paper titled: “Achieving Net Zero Embodied Carbon in Structural Material by 2050.”

The white paper examines in detail four transition tracks that make achieving net-zero embodied carbon in the built environment possible. The four transition tracks are:

1) Design Improvements
2) Greening the Electrical Grid
3) Material Production Improvements
4) Carbon Offsets

These four tracks may be combined in various proportions to reach net-zero, as shown in the table below.

The Carbon Working Group encourages structural engineers, architects, contractors, and others who wonder how the construction industry can meet critical carbon emission reduction targets to read this paper. It is available for free download at the SEI Sustainability Committee’s website:

Thursday, January 17, 2019

CarbonCure Expanding Concrete Markets

CarbonCure is a technology that injects a small amount of recycled CO2 into concrete during mixing thereby creating stronger concrete.  Some cement that can be saved to create the same strength concrete, thereby reducing the carbon footprint (emodied CO2) of the concrete mix.

Below is a press release for CarbonCure, announcing adoption of the technology in 15 additional mid-west ready mix concrete plants.  That makes a total of 126 plants in the U.S. and Canada using CarbonCure.  That's not a many of the estimated 5,500 plants, but the technology is win-win in terms of economy and sustainability, according to Jeff McPherson below. 

For example, there is one data point is mentioned below. Irving Materials saves 25 pounds of carbon dioxide per cubic yard.  When comparing the 650 pounds of carbon dioxide produced by a 4,000 psi class mix for the Great Lakes Midwest Region (as indicated in the NRMCA Benchmark Life Cycle Assessment Report), this amounts to about a 5% reduction in carbon dioxide per cubic yard.  That might also be percent cement savings by Irving Materials.

Here in Seattle, I attended a mixer hosted by Praxair (CO2 distributor) and CarbonCure to encourage local ready-mix plants to adopt their technology.  With Seattle being a key market for sustainable products, that adoption seems likely, but no announcements have been made yet.

CCT logo JPEG 80px high

Irving Materials, Inc. adds CarbonCure CO2 recycling technology to 15 ready mix concrete plants

GREENFIELD, INDIANAIrving Materials, Inc. (imi), a concrete and materials provider headquartered in Greenfield, Indiana, has adopted the CarbonCure CO2 recycling technology in 15 of its ready mix concrete plants across Indiana, Kentucky and Tennessee.
On average, every cubic yard of concrete made by imi Concrete with the CarbonCure Technology will save 25 pounds of carbon dioxide (CO2), reducing the carbon footprint of its concrete.
IMI Truck with CarbonCure System in Indianapolis
The CarbonCure Technology, which is being installed in 15 imi concrete plants, injects recycled CO2 into the concrete mix to improve the manufacturing process and reduce the concrete's carbon footprint. 
The CarbonCure Technology works by injecting recycled post-industrial CO2 into concrete during the manufacturing process. The CO2 undergoes a mineralization process that enhances the concrete’s compressive strength, which enables concrete producers to optimize concrete mixes without impacting the concrete’s quality or price.
Bob Haldrup
imi North Division
“imi Concrete is a family-owned and community-oriented business,” states Bob Haldrup, imi North Division President. “We are proud and humbled to provide the high-quality concrete products that make up the structural backbone of our communities. imi Concrete has been at the forefront of concrete innovation, including the development of the front discharge concrete mixer that is now an industry staple. CarbonCure fits within our vision to lead our industry with forward-thinking processes that provide better products for our customers.”
Founded in 1946, imi Concrete operates 155 active ready mix concrete plants across Indiana, Kentucky, Tennessee and Ohio.
imi Concrete first installed the CarbonCure Technology at its Whiteland, Indiana plant in July 2017, where it conducted extensive testing. The company initiated its expanded coverage of the carbon-reducing technology with 3 plant installations in November 2018. A further 11 plants are scheduled for installation in early 2019. Developers and contractors will be able to access concrete made with recycled CO2 from select imi Concrete locations by early spring.
Learn more about CarbonCure concrete by imi

 Jeff McPherson
VP Sales & Marketing

Jeff McPherson, VP Sales & Marketing, remarks, “At the end of the day, what matters to our customers is: Does the concrete meet structural performance and construction requirements and does it make good business sense? CarbonCure enables us to produce the same high-quality concrete that our customers have relied on us to provide for the past seven decades, but now with a reduced environmental impact.” 
The CarbonCure Technology is available in 126 concrete plants across the United States and Canada. The company recently announced its initial foray into international territories with an additional 3 plant installations at Pan-United, the leading concrete producer in Singapore. CarbonCure is a finalist in the $20 million NRG COSIA Carbon XPRIZE challenge, and has been named a Cleantech Group Global 100 company for the past 3 years. 
Add CarbonCure to your concrete plant
About CarbonCure
CarbonCure Technologies Inc. is the global leader in CO2 utilization technologies for the world’s most abundant man-made material: concrete. The retrofit CarbonCure Technology chemically mineralizes waste carbon dioxide during the concrete manufacturing process to make greener and stronger concrete. CarbonCure has partnered with over 125 concrete producers across North America and Asia to create new production cost savings, gain competitive sales advantages, and reduce the carbon footprint of the built environment.
For more information visit
For media inquiries contact Christie Gamble at

Tuesday, May 22, 2018

Mass Timber Conference Presentation PDFs

PDFs are available for many of the presentations from the 2018 Mass Timber Conference that was held in Portland in March. Check out the link below for the description of the presentations and to download.

Wednesday, April 25, 2018

Defining the "Reference Building" in WBLCA

In the new world of LEED v4, there are three points available for projects that complete a Whole Building LCA (WBLCA) and show improvement over a baseline "reference building". There is potential for the structure to greatly contribute to this improvement, but the rules for defining the reference structure are unclear.

SEI's Sustainability Committee is working to develop a guide, titled Guide to Definition of the Reference Building Structure and Strategies in Whole Building Life Cycle Assessment, to help define a standard and to ensure a nominal level of integrity in comparing structural designs using WBLCA.

For more information, check out this article from Structure Magazine.

CLT Bill Passes WA State Legislature

SB 5450, a bill that supports the expanded use of Cross Laminated Timber (CLT) in the state has been signed into law. The legislation required the State Building Code Council to adopt rues for the use of mass timber products for residential and commercial building construction, and passed with a large majority.

For more information, check out this blog post by Forterra.

Tuesday, April 17, 2018

Tokyo Skyscraper to be World's Tallest Wood Building

A proposed skyscraper in Tokyo would be the tallest wooden structure in the world. The 70-story tower will have a hybrid wood and steel structure. Read more about the project and other tall wood buildings around the world:

Model LCA Specifications

MKA has developed model specification templates for requiring LCA data for structural materials, which are available for download from the Carbon Leadership Forum. These templates are editable and open access, and MKA hopes to receive feedback from projects that utilize them to continue to improve the specifications.

Visit the CLF website for additional information and to download the templates: